In the case of natural materials, the information obtained through the tactile and visual senses are relatively unchanged :for example, glass has transparency and coldness, wood has grain and warmth,
and iron has weightiness and coldness. However, plastics present different faces depending on their type and variations. So people tend to have the impression that plastics are a substitute for natural materials.
However, there is no other new material with so many different possibilities.Since plastics are made of petroleum, efforts are being made to conserve natural resources, including the efforts to develop methods of using finite resources as efficiently as possible and methods of reducing the overall usage of natural resources by improving performance. Besides, methods that do not rely on petroleum for raw material are being looked for.