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US 4,375,447 AGranted
Method for forming an air-laid web of dry fibers
AssigneeKimberly-Clark Corporation
InventorRaymond Chung
Life of this patent
Estimating the term…
Abstract
Methods for pre-forming and feeding a lightly compacted batt of individualized fibers having a controlled cross-directional profile directly to a rotary fiber orienting and screening mechanism across the full width thereof so as to maintain a controlled cross-directional profile in an air-laid web of dry fibers formed in a high speed dry web forming system.
Claims12
A method of forming an air-laid web of dry fibers having a basis weight of from 7.5 to 50 lbs./2880 ft..sup.2 comprising:
- (a) forming a feed mat of dry fibrous materials having a controlled cross-directional profile;
- (b) compacting the feed mat to provide sufficient mat integrity to permit delivery to a remote point yet without sufficient compaction as to cause hydrogen bonding of fibers;
- (c) delivering the compacted feed mat to a forming head positioned over a moving foraminous forming surface;
- (d) dispersing the dry fibrous materials uniformly throughout the forming head in a rapidly moving aerated bed of individualized fibers, soft fiber flocs and aggregated fiber masses and in an environment maintained substantially free of fiber grinding and disintegrating forces;
- (e) continuously separating from the aerated bed a portion of the dry fibrous materials in the form of aggregated fiber masses having a bulk density in excess of 0.2 g./cc;
- (f) discharging said aggregated fiber masses from the forming head;
- (g) conveying the individualized fibers and soft fiber flocs from the forming head through a discharge opening at a fiber throughput rate of at least 0.5 lbs./hr. per square inch of discharge opening through an enclosed forming zone;
- (h) air-laying the individualized fibers and soft fiber flocs on the moving foraminous forming surface so as to form an air-laid web of randomly oriented dry individualized fibers and soft fiber flocs on the forming surface.
5 more elements
The method of forming a quality web of air-laid dry fibers on a high speed production basis comprising the steps of:
- (a) forming a feed mat of fibers having a controlled cross-directional profile;
- (b) lightly compacting the feed mat to provide sufficient mat integrity to permit delivery to a remote point yet without sufficient compaction as to cause hydrogen bonding of the fibers;
- (c) delivering the lightly compacted feed mat to a forming head positioned over a forming surface;
- (d) dispersing the dry fibrous materials comprising the feed mat uniformly thoughout forming head in a rapidly moving aerated bed of individualized fibers, soft fiber flocs and aggregated fiber masses and in an environment maintained substantially free of fiber grinding and disintegrating forces;
- (e) continuously separating a substantial portion of those fibrous materials delivered to the forming head having a bulk density in excess of 0.2 g./cc. from the aerated bed so as to separate a substantial portion of the aggregated fiber masses from the aerated bed;
- (f) discharging such separated fibrous materials including the aggregated fiber masses contained therein from the forming head;
- (g) conveying the individualized fibers and soft fiber flocs from the forming head at a fiber throughput rate anywhere in the range of 0.5 lbs./hr./in..sup.2 to at least 1.50 lbs./hr./in..sup.2 through an enclosed forming zone towards the moving foraminous forming surface in a rapidly moving air stream;
- (h) air-laying the individualized fibers and soft fiber flocs on the moving foraminous forming surface so as to form an air-laid web of randomly oriented dry individualized fibers and soft fiber flocs on the forming surface;
- and,
- (i) moving the foraminous forming surface at a controlled and selected speed so as to produce an air-laid web having any specific desired basis weight in, lbs./2880 ft..sup.2 ranging from at least as low as 13 lbs./2880 ft..sup.2 to in excess of 40 lbs./28880 ft..sup.2.
7 more elements
Dependencies are inferred from the claim text.