Papermaking fabric

Claim 2

A multi-ply woven fabric of mesh construction for use as a Fourdrinier forming belt and especially constructed to permit drainage therethrough of liquid from a slurry received thereon and to withstand flexing, high tension and abrasion incident to paper manufacture, said fabric comprising at least two plies each having an open area of at least about 9 percent and each ply being formed of respective interwoven warp and weft yarns, binder warp yarns interwoven with and interconnecting said plies, said plies including a top ply and a bottom ply, and said top ply being formed of a considerably greater number of warp yarns and weft yarns per square inch than said bottom ply with at least the warp yarns in said top ply being substantially smaller than the warp yarns in said bOttom ply, and the aggregate cross-sectional area of the yarns in said bottom ply being substantially greater than that of the yarns in said top ply per square inch of the fabric.

Claim 3

A multi-ply woven fabric according to claim 1, wherein said top ply includes about twice as many warp yarns therein as there are in said bottom ply.

Claim 4

A multi-ply woven fabric according to claim 1, wherein each of said binder warp yarns is interwoven back and forth between the two plies interconnected thereby and extends over spaced weft yarns only of said top ply, but extends under all of the weft yarns in said bottom ply.

Claim 5

A multi-ply woven fabric according to claim 1, wherein said binder warp yarns are smaller than said warp yarns in said top ply.

Claim 6

A multi-ply woven fabric according to claim 1, wherein the warp yarns in each of said plies extend over and under all of the weft yarns in the respective ply, and wherein only said binder warp yarns extend between and interconnect the adjacent plies.

Claim 7

A multi-ply woven fabric according to claim 1, including a plurality of stuffer warp yarns positioned between said top and bottom plies of the fabric.

Claim 8

A multi-ply woven fabric according to claim 1, including an additional intermediate ply of interwoven warp and weft yarns positioned between said top and bottom plies, and interconnect binder warp yarns connecting said intermediate ply to said top and bottom plies.

Claim 9

A multi-ply woven fabric according to claim 7, wherein said binder warp yarns include upper binder warp yarns extending between and interwoven with and interconnecting said top ply and said intermediate ply, and lower binder warp yarns extending between and interwoven with and interconnecting said intermediate ply and said bottom ply.

Claim 10

A multi-ply woven fabric of mesh construction for use as a Fourdrinier forming belt and especially constructed to permit drainage therethrough of liquid from a slurry received thereon and to withstand flexing, high tension and abrasion incident to paper manufacture, said fabric comprising at least two plies each having an open area of at least about 9 percent and each ply being formed of respective interwoven warp and weft yarns, binder warp yarns interwoven with and interconnecting said plies, said plies including a top ply and a bottom ply, said top ply being formed of a considerably greater number of warp yarns and weft yarns than said bottom ply, and the size of the warp and weft yarns in the bottom ply being substantially larger than the warp and weft yarns in the top ply.

Claim 11

A multi-ply woven fabric of mesh construction for use as a Fourdrinier forming belt and especially constructed to permit drainage therethrough of liquid from a slurry received thereon and to withstand flexing, high tension and abrasion incident to paper manufacture, said fabric comprising at least two plies each having an open area of at least about 9 percent and each ply being formed of respective interwoven warp and weft yarns, binder warp yarns interwoven with and interconnecting said plies, said plies including a top ply and a bottom ply, said top ply being formed of a considerably greater number of warp yarns and weft yarns than said bottom ply, and the size of the warp and weft yarns in the bottom ply being substantially larger than the warp and weft yarns in the top ply.

Claim 12

A multi-ply woven fabric of mesh construction for use as a Fourdrinier forming belt and especially constructed to permit drainage therethrough of liquid from a slurry received thereon and to withstand flexing, high tension and abrasion incident to paper manufacture, said fabric comprising at least two plies each formed of respective interwoven warp and weft yarns, the size and number of warp and weft yarns per square inch of each respective ply being such that at least about 9% of each ply is open area, binder warp yarns interwoven with and interconnecting said plies, said plies including a top ply and a bottom ply, said top ply being formed of relatively small warp yarns and relatively small weft yarns, said bottom ply including relatively large warp yarns compared to the warp yarns in said top ply, said top ply having about twice as many weft yarns therein as there are in said bottom ply per square inch of the fabric, said top ply also having a greater number of warp yarns therein than there are in said bottom ply, and the aggregate cross-sectional area of the warp yarns in said bottom ply being substantially greater than the aggregate cross-sectional area of the warp yarns in said top ply.

Claim 13

A multi-ply woven fabric of mesh construction for use as a Fourdrinier forming belt and especially constructed to permit drainage therethrough of liquid from a slurry received thereon and to withstand flexing, high tension and abrasion incident to paper manufacture, said fabric comprising at least two plies each formed of respective interwoven warp and weft yarns, the size and number of warp and weft yarns per square inch of each respective ply being such that at least about 9% of each ply is open area, binder warp yarns interwoven with and interconnecting said plies, said plies including a top ply and a bottom ply, said top ply being formed of relatively small warp yarns and relatively small weft yarns, said bottom ply including relatively large warp yarns compared to the warp yarns in said top ply, said top ply having about twice as many weft yarns therein as there are in said bottom ply per square inch of the fabric, said top ply also having a greater number of warp yarns therein than there are in said bottom ply, and the aggregate cross-sectional area of the warp yarns in said bottom ply being substantially greater than the aggregate cross-sectional area of the warp yarns in said top ply.

Claim 14

A multi-ply woven fabric of mesh construction for use as a Fourdrinier forming belt and especially constructed to permit drainage therethrough of liquid from a slurry received thereon and to withstand flexing, high tension and abrasion incident to paper manufacture, said fabric comprising a top ply, a bottom ply, and an intermediate ply between said top and bottom plies, binder warp yarns interwoven with and interconnecting all of said plies, each of said plies comprising interwoven warp and weft yarns with the size and number of warp and weft yarns per square inch of each ply being such that at least about 9 percent of each ply is open area, said top ply having about twice as many weft yarns therein as there are in said intermediate ply, said intermediate ply having about twice as many weft yarns therein as there are in said bottom ply, and the warp yarns and weft yarns of said intermediate and bottom plies being relatively large as compared to the warp yarns and weft yarns in said top ply.

Claim 15

A multi-ply woven fabric of mesh construction for use as a Fourdrinier forming belt and especially constructed to permit drainage therethrough of liquid from a slurry received thereon and to withstand flexing, high tension and abrasion incident to paper manufacture, said fabric comprising a top ply, a bottom ply, and an intermediate ply between said top and bottom plies, binder warp yarns interwoven with and interconnecting all of said plies, each of said plies comprising interwoven warp and weft yarns with the size and number of warp and weft yarns per square inch of each ply being such that at least about 9 percent of each ply is open area, said top ply having about twice as many weft yarns therein as there are in said intermediate ply, said intermediate ply having about twice as many weft yarns therein as there are in said bottom ply, and the warp yarns and weft yarns of said intermediate and bottom plies being relatively large as compared to the warp yarns and weft yarns in said top ply.

Claim 16

A multi-ply woven fabric of mesh construction for use as a Fourdrinier forming belt and especially constructed to permit drainage of liquid therethrough from a slurry received thereon and to withstand flexing, high tension and abrasion incident to paper manufacture, said fabric comprising at least two plies each formed of respective interwoven warp yarns and weft yarns with the size and number of warp and weft yarns per square inch of each ply being such that at least about 9 percent of each ply is open area, binder warp yarns interwoven with and interconnecting said plies, said plies including a top ply and a bottom ply, said top ply having a substantially greater number of warp yarns and weft yarns per square inch of said fabric than the bottom ply, said yarns in said top ply being substantially smaller than the yarns in said bottom ply, said binder warp yarns being relatively small and looped over weft yarns in said top ply and beneath weft yarns in said bottom ply, and a plurality of stuffer warp yarns positioned between said top and bottom plies of said fabric.

Claim 17

A multi-ply woven fabric of mesh construction for use as a Fourdrinier forming belt and especially constructed to permit drainage of liquid therethrough from a slurry received thereon and to withstand flexing, high tension and abrasion incident to paper manufacture, said fabric comprising at least two plies each formed of respective interwoven warp yarns and weft yarns with the size and number of warp and weft yarns per square inch of each ply being such that at least about 9 percent of each ply is open area, binder warp yarns interwoven with and interconnecting said plies, said plies including a top ply and a bottom ply, said top ply having a substantially greater number of warp yarns and weft yarns per square inch of said fabric than the bottom ply, said yarns in said top ply being substantially smaller than the yarns in said bottom ply, said binder warp yarns being relatively small and looped over weft yarns in said top ply and beneath weft yarns in said bottom ply, and a plurality of stuffer warp yarns positioned between said top and bottom plies of said fabric.

Claim 18

A multi-ply woven fabric of mesh construction for use as a Fourdrinier forming belt and especially constructed to permit drainage therethrough of liquid from a slurry received thereon and to withstand flexing, high tension and abrasion incident to paper manufacture, said fabric comprising at least two plies each having an open area of at least about 9% and each ply being formed of respective interwoven warp and weft yarns, binder yarns interwoven with and interconnecting said plies, said plies including a top ply and a bottom ply, and said top ply being formed of a considerably greater number of warp yarns and weft yarns per square inch than said bottom ply with at least the warp yarns in said top ply being substantially smaller than the warp yarns in said bottom ply, and the aggregate cross-sectional area of the yarns in said bottom ply being substantially greater than that of the yarns in said top ply per square inch of the fabric.

Claim 19

A multi-ply woven fabric of mesh construction for use as a Fourdrinier forming belt and especially constructed to permit drainage therethrough of liquid from a slurry received thereon and to withstand flexing, high tension and abrasion incident to paper manufacture, said fabric comprising at least two plies each having an open area of at least about 9% and each ply being formed of respective interwoven warp and weft yarns, binder yarns interwoven with and interconnecting said plies, said plies including a top ply and a bottom ply, and said top ply being formed of a considerably greater number of warp yarns and weft yarns per square inch than said bottom ply with at least the warp yarns in said top ply being substantially smaller than the warp yarns in said bottom ply, and the aggregate cross-sectional area of the yarns in said bottom ply being substantially greater than that of the yarns in said top ply per square inch of the fabric.