A bag can include walls formed of a material having multiple layers, which can include two polyolefin layers and a paper layer. Margaret Knight (1838–1914) applied for a patent using this model to demonstrate her machine that folded and pasted flat-bottomed paper bags.The image is printed on professional, acid free, archival matte fine art paper giving the image rich and vibrant colors. The original patent has been cleaned up and enhanced to create an attractive display piece for your home or office. She created a machine that made flat-bottomed paper bags. Put prepared shells in a paper bag, put in a hot oven and cook ten minutes. They patented the machine and afterwards founded the Union Paper Bag Company. A paper bag is a bag made of paper, usually kraft paper. Paper bags can be made either with virgin or recycled fibres to meet customers' demands. Margaret Knight (1838–1914) applied for a patent using this model to demonstrate her machine that folded and pasted flat-bottomed paper bags.