| 摘要 |
A method for producing an elongate sheet of material that includes barrier flaps which extend along the side-edges of said sheet in spaced relationship with respective side-edges, and which project up from the plane of the sheet, including placing along each edge-part of a first elongate web a narrower second elongate web, so the outer side-edges of respective second webs will lie edge-to-edge with the side-edges of the first web; placing along each edge-part of the first elongate web and on top of respective second webs a third elongate sheet narrower than the first sheet, so the outer side-edges of respective third webs will lie edge-to-edge with the side-edges of the first and second webs; joining the first, second and third webs together with a join extending along the outer side-edges of the webs; and swinging the third webs laterally outwards through 180° around the join lines. |
