# US 10,441,978 B2 · Fiber sheet > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,441,978 B2 - Document ID: US10441978B2 - Status: Granted - Kind: B2 - Application number: 15/308,007 - Filed: 2015-06-01 - Published: 2017-03-02 - Granted: 2019-10-15 - Earliest claimed: 2014-05-30 - Applicants: Kikuo Yamada - Inventors: Kikuo Yamada - Web page: https://patentgrep.com/patent/US10441978B2 ## CPC - A47K 7/00: Body washing or cleaning implements - A47K 7/03: containing soap or other cleaning ingredients, e.g. impregnated - A47K 10/16: Paper towels; Toilet paper; Holders therefor - A47L 13/17: containing cleaning agents (A47L13/19 takes precedence {; chemical compositions C11D17/049}) - B08B 1/143: {Wipes} - B32B 5/26: another layer {next to it} also being fibrous or filamentary {(relative arrangement of fibres or filaments of different layers B32B5/12)} - B32B 37/24: with at least one layer not being coherent before laminating, e.g. made up from granular material sprinkled onto a substrate (B32B37/15 takes precedence) - B32B 38/06: Embossing - D21H 27/002: {Tissue paper; Absorbent paper (D21H21/22, D21H27/02, D21H27/20 take precedence; toilet paper A47K10/00; absorbent pads for physiological fluids A61L15/16; making on paper-making machines D21F11/00)} - D21H 27/30: Multi-ply (for surface covering D21H27/18; making on paper-making machines D21F9/00, D21F11/00) - D21H 27/32: with materials applied between the sheets (attaching together paper or cardboard sheets B31F5/00; adhesives C09J) - D21H 27/38: at least one of the sheets having a fibrous composition differing from that of other sheets - B32B 2037/243: {Coating} - B32B 2309/105: Thickness - B32B 2555/00: Personal care - A47K: SANITARY EQUIPMENT; ACCESSORIES THEREFOR, e.g. TOILET ACCESSORIES - A47L: DOMESTIC WASHING OR CLEANING (brushes A46B; cleaning quantities of bottles or of other hollow articles of one kind B08B9/00; laundry D06F); SUCTION CLEANERS IN GENERAL (cleaning in general B08) - B08B: CLEANING IN GENERAL; PREVENTION OF FOULING IN GENERAL - B32B: LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM - D21H: PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR ## Abstract A fiber sheet having both a bulky feel and softness is provided. A fiber sheet (1) is provided with a surface sheet layer (5) and a softness imparting layer (6). The fiber sheet (1) is subjected to embossing and a binder is applied to the fiber sheet (1). The softness imparting layer (6) is constituted by a plurality of fibers; and the fibers exist densely in a compressed state in a region of a boundary face between the surface sheet layer (5) and the softness imparting layer (6). Additionally, the surface sheet layer (5) is a paper material formed from pulp paper or a material including pulp as a principal raw material; and the softness imparting layer (6) is formed from crushed pulp or a material including crushed pulp as a principal raw material. Furthermore, the surface sheet layer (5) is manufactured by a paper making process; and the softness imparting layer (6) is formed by laminating crushed pulp along a flow of an airflow on a surface of the surface sheet. Moreover, depressions are formed via the embossing and, thereafter, the binder is applied. ## Claims ### Claim 1 A fiber sheet, comprising: a first surface sheet layer and a second surface sheet layer each comprising a paper material formed from pulp paper or from a material including pulp as a principal raw material; and a softness imparting layer comprising a plurality of fibers of crushed pulp or a plurality of fibers of a material including crushed pulp as a principal raw material, and having a fiber density varying in a thickness direction of the fiber sheet such that the fibers are dense in a first side of the softness imparting layer and are sparse in a second side of the softness imparting layer opposite to the first side, wherein the fiber sheet is embossed to have a plurality of depressions and is applied with a binder, the binder is applied to the fiber sheet after the fiber sheet is embossed, and a first joining strength joining the first surface sheet layer and the softness imparting layer at the first side of the softness imparting layer is stronger than a second joining strength joining the second surface sheet layer and the softness imparting layer at the second side of the softness imparting layer. ### Claim 2 (depends on 1) The fiber sheet according to claim 1, wherein the softness imparting layer is formed by laminating crushed pulp on a surface of the first surface sheet layer while applying an airflow in the thickness direction of the fiber sheet. ### Claim 3 (depends on 1) The fiber sheet according to claim 1, wherein each of the first and second surface sheet layers has a thickness of from 0.003 cm to 0.050 cm. ### Claim 4 (depends on 1) The fiber sheet according to claim 1, wherein a density of each of the first and second surface sheet layers is from 0.05 g/cm3 to 0.5 g/cm3. ### Claim 5 (depends on 1) The fiber sheet according to claim 1, wherein an air permeability of each of the first and second surface sheet layers is from 500 mm3/(mm2×sec) to 2000 mm3/(mm2×sec). ### Claim 6 (depends on 1) The fiber sheet according to claim 1, wherein the softness imparting layer comprises a fiber having a length sufficient to bridge adjacent depressions. ### Claim 7 (depends on 1) The fiber sheet according to claim 1, wherein the binder is included in an amount of from 2 wt % to 9 wt %. ### Claim 8 (depends on 1) The fiber sheet according to claim 1, wherein the softness imparting layer includes 80% or more of pulp. ### Claim 9 (depends on 1) The fiber sheet according to claim 1, wherein the binder is applied to a surface of the first surface sheet layer opposite to a surface joined to the first side of the softness imparting layer and a surface of the second surface sheet layer opposite to a surface joined to the second side of the softness imparting layer. ### Claim 10 (depends on 1) The fiber sheet according to claim 1, wherein the fiber sheet is embossed in a dried state in atmosphere. ### Claim 11 (depends on 1) The fiber sheet according to claim 1, wherein the fiber sheet is embossed such that the first surface sheet layer has a flat shape and the second surface sheet layer has a depressed shape. ### Claim 12 (depends on 1) The fiber sheet according to claim 1, wherein the binder comprises at least one selected from the group consisting of carboxymethyl cellulose, polyvinyl alcohol, and ethylene-vinyl acetate copolymer resin. ### Claim 13 (depends on 1) The fiber sheet according to claim 1, wherein the first and second surface sheet layers of the surface sheet layer have a same thickness and composition. ### Claim 14 (depends on 1) The fiber sheet according to claim 1, wherein the fiber sheet is embossed to form the plurality of depressions uniformly throughout an entire surface of the fiber sheet. ### Claim 15 (depends on 1) The fiber sheet according to claim 1, wherein the fiber sheet does not comprise a releasing agent. ### Claim 16 A fiber sheet, comprising: a surface sheet layer comprising a paper material formed from pulp paper or from a material including pulp as a principal raw material, the surface sheet layer having an air permeability of from 500 to 2000 mm3/(mm2×sec); and a softness imparting layer laminated on the surface sheet layer and comprising a plurality of fibers of crushed pulp or a plurality of fibers of a material including crushed pulp as a principal raw material, wherein the fiber sheet is compressed or pressed in a non-wet state to process at least one surface of the fiber sheet, and then applied with at least one of a binder and a water-based composition, and the softness imparting layer is laminated on the surface sheet layer by an airflow permeating the surface sheet layer. ### Claim 17 (depends on 16) The fiber sheet according to claim 16, wherein the fiber sheet has a bulk portion comprising depressions, protrusions, or both, such that the bulk portion increases a bulkiness of the fiber sheet. ### Claim 18 (depends on 16) The fiber sheet according to claim 16, wherein the fiber sheet is compressed or pressed by a roller. ### Claim 19 (depends on 16) The fiber sheet according to claim 16, wherein the softness imparting layer has a fiber density varying in a thickness direction of the fiber sheet such that the fibers are dense in a first side of the softness imparting layer and are sparse in a second side of the softness imparting layer opposite to the first side. ### Claim 20 (depends on 16) The fiber sheet according to claim 16, wherein the fiber sheet does not comprise a releasing agent. ### Claim 21 (depends on 16) The fiber sheet according to claim 16, wherein the softness imparting layer comprises a plurality of fibers of a material including crushed pulp as a principal raw material, and the material includes 50% or more of the crushed pulp. ### Claim 22 (depends on 16) The fiber sheet according to claim 16, wherein the crushed pulp in the softness imparting layer has a basis weight of 60 g/m2 or less. ### Claim 23 (depends on 15) A method of making the fiber sheet of claim 15, comprising: laminating the softness imparting layer to the surface sheet layer by using the airflow such that the softness imparting layer comprises the plurality of fibers of the material comprising 50% or more of pulp and that the surface sheet layer has the air permeability of from 500 to 2000 mm3/(mm2×sec), thereby producing a laminated sheet; compressing or pressing the laminated sheet in the non-wet state to process the at least one surface of the laminated sheet; and applying at least one of the binder and the water-based composition to the laminated sheet. ### Claim 24 (depends on 16) A cleaning article, comprising: the fiber sheet according to claim 16.