Patent ID: 7314440

Claim:
A longitudinal former of a web-processing machine comprising: a longitudinal web former support body adapted to form a longitudinal fold in a continuous web moving in a web travel direction over said web former support body; first and second leg areas of said web former support body, said first and second leg areas each extending generally in said web travel direction, each having a rigid, air permeable leg area support surface, both said first and second leg areas being adapted to concurrently engage the web being longitudinally folded during travel of the web over said web former support body, said first and second leg areas of said web former support body converging in said web travel direction with respect to each other, and at an acute angle; a nose section of said web former support body, said nose section of said web former support body being located at a convergence of said first and second converging leg areas of said web former support body, said nose section of said web former support body having a rigid, air permeable nose support surface adapted to engage the web being longitudinally formed by said web former support body, said nose section defining a longitudinal fold to be imparted to the web moving over said web former support body; a first surface layer of a micro-porous air permeable material on said support surfaces of each of said first and second converging leg areas of said web former support body, said first surface layer having a plurality of micro-openings of open pores of said micro-porous, air permeable material for the exit of a fluid under pressure and with a mean diameter of less than 150 μm, said first surface layer providing a first fluid output between said leg support surfaces and the web moving over said web former support body and having a first fluid permeability per unit of area; and a second surface layer of a micro-porous, air permeable material on said nose support surface of said nose section of said web former support body, said second surface layer having a plurality of micro-openings of open pores of said micro-porous material for the exit of fluid under pressure and with a mean diameter of less than 150 μm, said second surface layer providing a second fluid output, greater than said first fluid output, between said nose support surface and the web moving over said web former support body, and having a second fluid permeability per unit of area, said second fluid permeability being greater than said first fluid permeability.