EP0159630A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Selective layering of superabsorbents in meltblown substrates
Assignee: Kimberly Clark Corp
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Filing: 1985-04-11
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Granted: —
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Expires: 2005-04-11
Abstract
Abstract The invention generally provides for formation of meltblown material containing wood fiber on to a continuous foraminous belt. During formation a polymer and wood fiber first layer is applied to a moving belt from at least one bank of meltblown forming apparatus. This first layer does not contain superabsorbent. The belt carrying the first layer passes beneath at least one further source of meltblown fiber into which superabsorbent is added along with the wood fibers. This provides at least one additional layer integrally connected to the first-formed layer and having superabsorbent properties. The first layer acts to aid in trapping of any superabsorbent which is not immediately entangled in the meltblown and wood fibers and prevents it passing through the forming belt.
Inventors
- 👤 Timothy M. Mcfarland
- 👤 Theodore Bernard Lang
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-27 23:02
CPC Classifications
A; A61; A61F; A61F13/00; A61F13/15; A61F13/53; A61F13/534; A61F13/15577; A61F13/15617; A61F13/15658; A61L; A61L15/00; A61L15/16; A61L15/42; A61L15/60; D; D04; D04H; D04H1/00; D04H1/40; D04H1/54; D04H1/56; D04H3/00; D04H3/08; D04H3/16; A61F2013/15821; A61F2013/15934; A61F2013/15967; A61F2013/530481; A61F2013/530489; A61F2013/530496; Y; Y10; Y10S; Y10S428/00; Y10S428/913; Y10T; Y10T428/00; Y10T428/24; Y10T428/24479; Y10T428/24612; Y10T428/25; Y10T428/253; Y10T442/00; Y10T442/60; Y10T442/608; Y10T442/614; Y10T442/619; Y10T442/699
Claims Analysis
Total Claims: 26
Claim 1
Independent Claim
217 words
A layered nonwoven fabric-like material having a unique combination of strength, absorbency and hand, said material comprising A. at least one normal absorbent layer of a gas-formed matrix of thermoplastic polymeric meltblown microfibers and a multiplicity of individualized and gas-formed staple fibers disposed throughout said matrix of microfibers and engaging at least some of said microfibers to space the microfibers apart from each other, said staple fibers being interconnected by and held captive within said matrix of microfibers by mechanical entanglement of said microfibers with said staple fibers, the mechanical entanglement and interconnection of said microfibers and staple fibers forming a coherent integrated fibrous structure, and B. at least one highly-absorbent layer integrally connected to said normal absorbent layer, said highly-absorbent layer comprising a gas-formed matrix of thermoplastic polymeric meltblown microfibers and a multiplicity of individualized and gas-formed staple fibers and superabsorbent particles disposed throughout said matrix of microfibers and engaging at least some of said microfibers to space the microfibers apart from each other, said staple fibers and said superabsorbent being interconnected by and held captive within said matrix of microfibers by mechanical entanglement of said microfibers with said staple fibers and said superabsorbent particles, the mechanical entanglement and interconnection of said microfibers and staple fibers and said superabsorbent particles forming a coherent integrated fibrous structure.
Claim 2
Dependent Claim
217 words
A layered nonwoven fabric-like material having a unique combination of strength, absorbency and hand, said material comprising A. at least one normal absorbent layer of a gas-formed matrix of thermoplastic polymeric meltblown microfibers and a multiplicity of individualized and gas-formed staple fibers disposed throughout said matrix of microfibers and engaging at least some of said microfibers to space the microfibers apart from each other, said staple fibers being interconnected by and held captive within said matrix of microfibers by mechanical entanglement of said microfibers with said staple fibers, the mechanical entanglement and interconnection of said microfibers and staple fibers forming a coherent integrated fibrous structure, and B. at least one highly-absorbent layer integrally connected to said normal absorbent layer, said highly-absorbent layer comprising a gas-formed matrix of thermoplastic polymeric meltblown microfibers and a multiplicity of individualized and gas-formed staple fibers and superabsorbent particles disposed throughout said matrix of microfibers and engaging at least some of said microfibers to space the microfibers apart from each other, said staple fibers and said superabsorbent being interconnected by and held captive within said matrix of microfibers by mechanical entanglement of said microfibers with said staple fibers and said superabsorbent particles, the mechanical entanglement and interconnection of said microfibers and staple fibers and said superabsorbent particles forming a coherent integrated fibrous structure.
Claim 3
Dependent Claim
20 words
The material of Claim 1 wherein said material comprises one said normal absorbent layer and one said highly absorbent layer.
Claim 4
Dependent Claim
27 words
The material of Claim 1 wherein said material comprises a normal absorbent layer on each surface and an interior layer comprising at least one highly absorbent layer.
Claim 5
Dependent Claim
32 words
The material of Claim 1 wherein said at least one highly absorbent layer comprises about 10 to about 60 percent by weight of superabsorbent and said staple fiber comprises wood pulp fibers.
Claim 6
Dependent Claim
29 words
The material of Claim 4 wherein said remaining portion of said at least one highly absorbent layer comprises about 70 percent wood pulp fibers and about 30 percent polymer.
Claim 7
Dependent Claim
9 words
The material of Claim 1 having an embossed pattern.
Claim 8
Dependent Claim
28 words
The material of Claim 1 wherein said at least one normal absorbent layer and said at least one highly absorbent layer are integrally connected by intermingling of fibers.
Claim 9
Dependent Claim
14 words
The material of Claim 1 wherein a impervious sheet is adhered to one surface.
Claim 10
Dependent Claim
14 words
The material of Claim 1 wherein a pervious sheet is adhered to one surface.
Claim 11
Independent Claim
392 words
A method of forming a nonwoven fabric-like material having a unique combination of strength, absorbency and hand, said method comprising: A. forming at least one normal absorbency coform layer by the steps of: (1) forming a primary air stream containing meltblown microfibers comprising generally discontinuous thermoplastic polymeric microfibers, said primary air stream having a temperature in the range of from about 600° F. to about 700° F.; (2) forming a secondary air stream containing individualized staple fibers; (3) merging said secondary stream with said primary stream under turbulent conditions to form an integrated air stream containing a thorough mixture of said microfibers and said staple fibers; and (4) directing said integrated air stream onto a moving forming surface to air-form a matrix of said microfibers in which at least some of said microfibers are engaged by said individualized staple fibers to space the microfibers apart from each other, and said individualized staple fibers are disposed throughout said matrix of microfibers and interconnected by and held captive within said matrix by mechanical entanglement of said microfibers with said staple fibers, the mechanical entanglement and interconnection of said microfibers and staple fibers forming a first-layer coherent integrated fibrous structure; B. forming at least one highly absorbent layer by the steps of: (1) forming a second primary air stream containing meltblown microfibers comprising generally discontinuous thermoplastic polymeric microfibers; (2) forming a second secondary air stream containing individualized wood pulp fibers; (3) forming a tertiary stream of superabsorbent particles; (4) merging said second secondary stream and said tertiary stream with said second primary stream under turbulent conditions to form a second integrated air stream containing a thorough mixture of said superabsorbent particles, said microfibers and said wood pulp fibers; and (5) directing said second integrated air stream onto said moving forming surface carrying said first layer to air-form second matrix of said microfibers in which at least some of said microfibers and said superabsorbent particles are engaged by said individualized wood pulp fibers to space the microfibers apart from each other, and said individualized wood pulp fibers and said superabsorbent particles are disposed throughout said matrix of microfibers and interconnected by and held captive within said matrix by mechanical entanglement of said microfibers with said wood pulp fibers, the mechanical entanglement and interconnection of said microfibers and wood pulp fibers forming a coherent integrated fibrous structure.
Claim 12
Independent Claim
392 words
A method of forming a nonwoven fabric-like material having a unique combination of strength, absorbency and hand, said method comprising: A. forming at least one normal absorbency coform layer by the steps of: (1) forming a primary air stream containing meltblown microfibers comprising generally discontinuous thermoplastic polymeric microfibers, said primary air stream having a temperature in the range of from about 600° F. to about 700° F.; (2) forming a secondary air stream containing individualized staple fibers; (3) merging said secondary stream with said primary stream under turbulent conditions to form an integrated air stream containing a thorough mixture of said microfibers and said staple fibers; and (4) directing said integrated air stream onto a moving forming surface to air-form a matrix of said microfibers in which at least some of said microfibers are engaged by said individualized staple fibers to space the microfibers apart from each other, and said individualized staple fibers are disposed throughout said matrix of microfibers and interconnected by and held captive within said matrix by mechanical entanglement of said microfibers with said staple fibers, the mechanical entanglement and interconnection of said microfibers and staple fibers forming a first-layer coherent integrated fibrous structure; B. forming at least one highly absorbent layer by the steps of: (1) forming a second primary air stream containing meltblown microfibers comprising generally discontinuous thermoplastic polymeric microfibers; (2) forming a second secondary air stream containing individualized wood pulp fibers; (3) forming a tertiary stream of superabsorbent particles; (4) merging said second secondary stream and said tertiary stream with said second primary stream under turbulent conditions to form a second integrated air stream containing a thorough mixture of said superabsorbent particles, said microfibers and said wood pulp fibers; and (5) directing said second integrated air stream onto said moving forming surface carrying said first layer to air-form second matrix of said microfibers in which at least some of said microfibers and said superabsorbent particles are engaged by said individualized wood pulp fibers to space the microfibers apart from each other, and said individualized wood pulp fibers and said superabsorbent particles are disposed throughout said matrix of microfibers and interconnected by and held captive within said matrix by mechanical entanglement of said microfibers with said wood pulp fibers, the mechanical entanglement and interconnection of said microfibers and wood pulp fibers forming a coherent integrated fibrous structure.
Claim 13
Dependent Claim
25 words
The method of Claim 10 wherein the steps 1 - 4 of Section A are repeated after one highly-absorbent layer of Section B is formed.
Claim 14
Dependent Claim
22 words
The method of Claim 10 further comprising placing a pervious web onto the forming surface prior to the steps of Section A.
Claim 15
Dependent Claim
14 words
The method of Claim 10 wherein air is withdrawn from below the forming surface.
Claim 16
Dependent Claim
15 words
The method of Claim 10 wherein after all layers are formed the material is embossed.
Claim 17
Dependent Claim
13 words
The method of Claim 10 wherein the layers are connected by intermingled fibers.
Claim 18
Dependent Claim
250 words
An absorbent dressing comprising an impervious polymer backing sheet, a pervious body-side liner, and an absorbent core located between said pervious liner and said impervious backing wherein said absorbent material comprises a layered nonwoven fabric-like material having a unique combination of strength, absorbency and hand, said material comprising: A. at least one normal absorbent layer of a gas-formed matrix of thermoplastic polymeric meltblown microfibers and a multiplicity of individualized and gas-formed staple fibers disposed throughout said matrix of microfibers and engaging at least some of said microfibers from each other to space the microfibers apart from each other, said staple fibers being interconnected by and held captive within said matrix of microfibers by mechanical entanglement of said microfibers with said staple fibers, the mechanical entanglement and interconnection of said microfibers and staple fibers forming a coherent integrated fibrous structure, and B. at least one highly-absorbent layer integrally connected to said normal absorbent and highly-absorbent layer comprising a gas-formed matrix of thermoplastic polymeric meltblown microfibers and a multiplicity of individualized and gas-formed staple fibers and superabsorbent particles disposed throughout said matrix of microfibers and engaging at least some of said microfibers to space the microfibers apart from each other, said staple fibers and said superabsorbent being interconnected by and held captive within said matrix of microfibers by mechanical entanglement of said microfibers with said staple fibers and said superabsorbent particles, the mechanical entanglement and interconnection of said microfibers and staple fibers and said superabsorbent particles forming a coherent integrated fibrous structure.
Claim 19
Dependent Claim
250 words
An absorbent dressing comprising an impervious polymer backing sheet, a pervious body-side liner, and an absorbent core located between said pervious liner and said impervious backing wherein said absorbent material comprises a layered nonwoven fabric-like material having a unique combination of strength, absorbency and hand, said material comprising: A. at least one normal absorbent layer of a gas-formed matrix of thermoplastic polymeric meltblown microfibers and a multiplicity of individualized and gas-formed staple fibers disposed throughout said matrix of microfibers and engaging at least some of said microfibers from each other to space the microfibers apart from each other, said staple fibers being interconnected by and held captive within said matrix of microfibers by mechanical entanglement of said microfibers with said staple fibers, the mechanical entanglement and interconnection of said microfibers and staple fibers forming a coherent integrated fibrous structure, and B. at least one highly-absorbent layer integrally connected to said normal absorbent and highly-absorbent layer comprising a gas-formed matrix of thermoplastic polymeric meltblown microfibers and a multiplicity of individualized and gas-formed staple fibers and superabsorbent particles disposed throughout said matrix of microfibers and engaging at least some of said microfibers to space the microfibers apart from each other, said staple fibers and said superabsorbent being interconnected by and held captive within said matrix of microfibers by mechanical entanglement of said microfibers with said staple fibers and said superabsorbent particles, the mechanical entanglement and interconnection of said microfibers and staple fibers and said superabsorbent particles forming a coherent integrated fibrous structure.
Claim 20
Dependent Claim
17 words
The absorbent dressing of Claim 16 wherein a normal absorbent layer is located adjacent said pervious liner.
Claim 21
Dependent Claim
28 words
The dressing of Claim 17 wherein said at least one normal absorbent layer and said at least one highly absorbent layer are integrally connected by intermingling of fibers.
Claim 22
Dependent Claim
28 words
The dressing of Claim 1 wherein said absorbent material comprises a normal absorbent layer on each surface and an interior layer comprising at least one highly absorbent layer.
Claim 23
Dependent Claim
52 words
A composite absorbent sheet comprising a normal absorption layer comprising at least one normal absorption layer of entangled air-formed meltblown fibers and at least one high-absorption layer of entangled meltblown fibers integrally connected to said first layer and formed of a coherent web of entangled meltblown fibers having superabsorbent particles entangled therein.
Claim 24
Dependent Claim
52 words
A composite absorbent sheet comprising a normal absorption layer comprising at least one normal absorption layer of entangled air-formed meltblown fibers and at least one high-absorption layer of entangled meltblown fibers integrally connected to said first layer and formed of a coherent web of entangled meltblown fibers having superabsorbent particles entangled therein.
Claim 25
Dependent Claim
24 words
A composite sheet in accordance with Claim 20 wherein at least one of said layers further comprises staple fibers thereby forming a coform layer.
Claim 26
Dependent Claim
18 words
The composite of Claim 21 wherein an exterior layer comprises a normal absorption layer of said meltblown fibers.
References Cited (Backward Citations)
No citation records indexed.
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