Vacuum bags, food vacuum bags, hello,. A process for molding reinforced plastics in which a sheet of flexible transparent made of ... Such as nylon or mylar plastics is placed over the lay-up on the mold and sealed. A vacuum is applied between the sheet and the lay-up. The entrapped air is removed by the vacuum and the part is placed in an oven or autoclave. The addition of pressure further results in higher fiber concentration and provides better adhesion between layers of sandwich construction. Also known as vacuum bagging. . Thanking yours,. Ronak dave. +971 529062693.