TPU plastic

TPU is also soft, and belongs to the soft rubber product like silica gel. Many people do not understand the difference between silica gel and TPU, and even some Taobao sellers can't figure it out, saying that the soft is silica gel. TPU belongs to the plastic category, and the product is made by injection molding process. After the pellets of plastic rice are heated and melted, they are injected into the plastic mold with a barrel to make the product. Silica gel belongs to rubber, and the molding process uses vulcanization molding. The silicone mold is opened up and down. Cut the pieces of silicone raw materials, put them in the mold, and heat and press to make the product.

Generally, plastic products will have a plastic inlet, which must be trimmed after the product is injection molded. If the trimming is not good, the appearance will be greatly affected. Silicone does not have a glue inlet, but there is a ring of burrs around it that needs to be repaired. If the mold is rubbish, this ring of burrs will be more obvious, just like a dog chewing. From the feel of the hand, the hardness of TPU is generally harder than that of silicone, and the elasticity of hand pinching is stronger, while the elasticity of silicone is slightly worse. You can compare TPU to the feel of muscles, and the feel of silicone to fat. From the outside, TPU can be made very transparent, but silica gel is not. The most transparent is very hazy, like thick fog. It is precisely because of the transparent feeling of TPU that is more popular with users. Moreover, there are still many high-grade TPU products, with relatively strong selectivity, and more pattern changes than silica gel. The disadvantage of TPU is that it is easy to deform and yellow. After three or four months of use, if you happen to buy a transparent white or other light-colored product, it will easily turn yellow. If the material is not good, the surface will even fog. Or sticky.