Zinsinsi za mitengo ina nthawi zambiri zimapanga utomoni.Kale mu 1872, katswiri wa zamankhwala wa ku Germany A. Bayer anapeza koyamba kuti phenol ndi formaldehyde zimatha kupanga mwamsanga zotupa zofiira-bulauni kapena zinthu zomata zikatenthedwa ndi acidic, koma sizingayeretsedwe ndi njira zakale.ndi kusiya exp ...
Chikwama cha vest ndi mtundu wa thumba la pulasitiki wamba.Ponena za chifukwa chake amatchedwa "chikwama cha vest", monga momwe dzinalo likusonyezera, zimatsimikiziridwa ndi maonekedwe ake: mawonekedwe ake amafanana ndi vest, choncho dzina.Chikwama cha vest ndi chosavuta kupanga ndipo chimakhala ndi ntchito zambiri.Zakhala zofunikira kwambiri ...