Wet-process nonwoven fabric and method for producing the same

The present invention provides a wet-process nonwoven fabric constituted of inorganic fibers including bundled inorganic fibers and a binder ingredient with which the fibers are bonded, wherein the average number of fiber per bundle is 1.5 to 20 and the average Z/X value represented by Z/X value=(number of adjacent fibers in the thickness direction of each bundle)/(number nonwoven fiber has a section in which the average value of Z/X, which is represented by (the number of fibers in each bundle which are disposed adjacently in the thickness direction)/(the number of fibers in each bundle which are disposed adjacently in the plane direction) (average Z/x value) is 0.9 or lower, and a wet process for producing a nonwoven fabric which comprises a step in which inorganic fibers are dispersed in an aqueous medium in the presence of an anionic dispersion stabilizer, a step in which a cationic compound is added to the resultant fiber dispersion to bundle the fibers and producing a fiber dispersion containing fiber bundles, a step in which the resultant fiber dispersion containing fiber bundles is formed into a sheet by a wet papermaking method; and a step in which a binder is applied to the obtained sheet. The nonwoven fabric is a nonwoven inorganic fiber fabric having a high density.