US4016628A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method and apparatus for forming absorbent articles
Assignee: Kimberly Clark Tissue Co
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Filing: 1974-08-12
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Granted: 1977-04-12
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Expires: 1994-08-12
Abstract
Abstract An absorbent article includes an air-laid fibrous web having a medial portion of a greater basis weight than flanking end and side portions. The fibers forming one surface of the web are adhesively bonded together to provide an abrasion resistant, nonpilling, facing layer, and also to aid in maintaining the structural integrity of the web. The fibers forming the other surface of the web are either adhesively bonded together, or a separate backing sheet, preferably in the form of a water-proof plastic sheet, is adhered directly to the other surface of the web to form a stabilized backing layer. The above contructions are adapted for use as disposable diapers. Apparatus of this invention includes a vacuum box having an open end underlying a discrete section of a foraminous forming surface so that regions of the forming surface extend beyond the open end of the vacuum box. Vacuum connection means permit the establishment of a different pressure drop across the discrete section of the foraminous forming surface overlying the open end of the vacuum box than through regions of the foraminous forming surface extending beyond the vacuum box. Drive means move the foraminous forming surface and vacuum box in registration with each other through a web forming area for maintaining the same discrete section of the foraminous forming surface in overlying relationship with the open end of the vacuum box as the foraminous forming surface and the vacuum box are moved through the web forming area. The method of this invention employs the above-described apparatus in which the foraminous forming surface extends beyond, and completely circumscribes the open end of the vacuum box. A greater pressure drop is established through the discrete section of the foraminous forming surface overlying the vacuum box than through the regions extending beyond the vacuum box to form a fibrous web having a medial portion with a greater basis weight of fibers therein than in flanking end and side portions of the web.
Inventors
- 👤 Charles C. Kolbach
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 06:31
CPC Classifications
A; A61; A61F; A61F13/00; A61F13/15; A61F13/53; A61F13/531; A61F13/532; A61F13/15577; A61F13/15617; A61F13/15658; A61F13/534; A61F13/53409; A61F13/53436; A61F2013/5326
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
301 words
An apparatus capable of use in forming an absorbent, air-laid, nonwoven fibrous web having regions of different basis weights therein, said apparatus including a fiberizing means for separating fibers from a feed mat and entraining said separated fibers in air to form an air suspension of fibers, a formation chamber including a passageway into which said air suspension of fibers is directed, said passageway having a downstream end which is closed by a movable forming surface, regions of said forming surface underlying said passageway constituting a forming area in which the web is formed; the improvement wherein: A. said forming surface including a plurality of discrete, three-dimensional compartments which are spaced from each other and which include foraminous bottom walls, said forming surface further including other foraminous sections completely circumscribing the three-dimensional compartments; B. a plurality of vacuum boxes being spaced from each other and having open ends underlying respective three-dimensional compartments, the other foraminous sections extending beyond the open ends of said vacuum boxes; C. first vacuum connection means communicating with said vacuum boxes for permitting the establishment of a desired pressure drop through the bottom walls of the three-dimensional compartments; D. second vacuum connection means communicating with the other foraminous sections of the forming surface for permitting the establishment of a desired pressure drop through said other foraminous sections of said forming surface; and E. drive means for moving the forming surface and vacuum boxes at the same speed through the forming area for maintaining the open end of each vacuum box in alignment with a respective three-dimensional compartment in said forming area, whereby, in the forming area, the pressure drop established through the bottom walls of the three-dimensional compartments can be selected substantially independently of the pressure drop established through the other foraminous sections of the forming surface.
Claim 2
Independent Claim
301 words
An apparatus capable of use in forming an absorbent, air-laid, nonwoven fibrous web having regions of different basis weights therein, said apparatus including a fiberizing means for separating fibers from a feed mat and entraining said separated fibers in air to form an air suspension of fibers, a formation chamber including a passageway into which said air suspension of fibers is directed, said passageway having a downstream end which is closed by a movable forming surface, regions of said forming surface underlying said passageway constituting a forming area in which the web is formed; the improvement wherein: A. said forming surface including a plurality of discrete, three-dimensional compartments which are spaced from each other and which include foraminous bottom walls, said forming surface further including other foraminous sections completely circumscribing the three-dimensional compartments; B. a plurality of vacuum boxes being spaced from each other and having open ends underlying respective three-dimensional compartments, the other foraminous sections extending beyond the open ends of said vacuum boxes; C. first vacuum connection means communicating with said vacuum boxes for permitting the establishment of a desired pressure drop through the bottom walls of the three-dimensional compartments; D. second vacuum connection means communicating with the other foraminous sections of the forming surface for permitting the establishment of a desired pressure drop through said other foraminous sections of said forming surface; and E. drive means for moving the forming surface and vacuum boxes at the same speed through the forming area for maintaining the open end of each vacuum box in alignment with a respective three-dimensional compartment in said forming area, whereby, in the forming area, the pressure drop established through the bottom walls of the three-dimensional compartments can be selected substantially independently of the pressure drop established through the other foraminous sections of the forming surface.
Claim 3
Dependent Claim
80 words
The apparatus according to claim 1, including a masking member having air-impervious sections disposed between the open end of the vacuum boxes and the bottom walls of the three-dimensional compartments in the forming area for preventing the establishment of a pressure drop in different regions of each three-dimensional compartment for different periods of time, whereby a different effective volumetric air flow is established through the different regions to effect deposition of a different weight of fibers in said different regions.
Claim 4
Dependent Claim
24 words
The apparatus according to claim 1, wherein said foraminous forming surface is a cylinder and said vacuum boxes are mounted internally of said cylinder.
Claim 5
Independent Claim
209 words
A method for forming an absorbent, air-laid, nonwoven fibrous web having at least a medial portion of a greater basis weight than flanking end and side portions, said method comprising the steps of: A. directing a forming surface through a web forming area, said forming surface including discrete three-dimensional compartments which are spaced from each other and which include foraminous bottom walls, said forming surface further including other foraminous sections completely circumscribing said three-dimensional compartments; B. directing a plurality of vacuum voxes which are spaced apart from each other through the web forming area so that open ends of the vacuum boxes remain in alignment with the bottom walls of the three-dimensional compartments and the other foraminous sections of the forming surface which completely circumscribe the three-dimensional compartments extend beyond the open end of said vacuum boxes; C. directing an air suspension of fibers toward the forming surface in the web forming area; and D. establishing, in said web forming area, a greater pressure drop through the vacuum boxes and overlying bottom walls of the three-dimensional compartments than through the other foraminous sections of the forming surface to thereby deposit a greater weight of fibers from the air suspension into the three-dimensional compartments than on said other foraminous sections.
Claim 6
Independent Claim
209 words
A method for forming an absorbent, air-laid, nonwoven fibrous web having at least a medial portion of a greater basis weight than flanking end and side portions, said method comprising the steps of: A. directing a forming surface through a web forming area, said forming surface including discrete three-dimensional compartments which are spaced from each other and which include foraminous bottom walls, said forming surface further including other foraminous sections completely circumscribing said three-dimensional compartments; B. directing a plurality of vacuum voxes which are spaced apart from each other through the web forming area so that open ends of the vacuum boxes remain in alignment with the bottom walls of the three-dimensional compartments and the other foraminous sections of the forming surface which completely circumscribe the three-dimensional compartments extend beyond the open end of said vacuum boxes; C. directing an air suspension of fibers toward the forming surface in the web forming area; and D. establishing, in said web forming area, a greater pressure drop through the vacuum boxes and overlying bottom walls of the three-dimensional compartments than through the other foraminous sections of the forming surface to thereby deposit a greater weight of fibers from the air suspension into the three-dimensional compartments than on said other foraminous sections.
Claim 7
Dependent Claim
46 words
The method according to claim 4, including the step of establishing different effective volumetric air flows through different regions of each discrete three-dimensional compartment of said foraminous forming surface, whereby the medial portions of said fibrous web are formed with regions having different basis weights therein.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-04-11 | 1980-10-11 | 1981-04-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-04-11 | 1984-10-11 | 1985-04-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-04-11 | 1988-10-11 | 1989-04-12 | $7700.00 | Window Closed / Lapsed |