Layered, absorbent structure, an absorbent article comprising th

Details Layered, absorbent structure, an absorbent article comprising th Layered, absorbent structure, an absorbent article comprising th

1996-11-21

1999-08-31

Yu, Mickey

Surgery

Means and methods for collecting body fluids or waste material

Absorbent pad for external or internal application and...

604378, A61F 1315, A61F 1320

Patent

active

059447060

DESCRIPTION:

BRIEF SUMMARY
CROSS REFERENCE TO RELATED APPLICATIONS

This application claims priority under 35 USC .sctn.371 to International Patent Application No. PCT/EP94/04215, filed Dec. 19, 1994, which claims priority to Italian Patent Application No. TO93A001028, filed Dec. 31, 1993.


BACKGROUND OF THE INVENTION

The present invention relates to layered, absorbent structures constituted by fibrous layers with interposed particles of hydrogelling absorbent material.
The structures may be used as absorbent elements in disposable absorbent articles such as absorbent articles for incontinent adults, babies' nappies, sanitary towels, dressings and the like.
Disposable absorbent articles are well known and all have absorbent elements for absorbing and retailing body fluids; an absorbent element must be able to acquire liquid rapidly and to distribute it internally so as to prevent leakages and must also have a good capacity to retain the fluids when subjected to the normal pressures of use.
Absorbent elements made mainly of hydrophilic fibrous material such as, for example, pads of cellulose fibres, layers of wadding, or the like generally have satisfactory characteristics as regards their liquid-absorption rate and can distribute the liquid effectively within them but are very ineffective from the point of view of retention when subjected to the normal pressures of use.
The use of hydrogelling absorbent materials in combination with hydrophilic fibres in order to increase the absorption and retention capacities of the absorbent elements is known.
Hydrogelling absorbent materials, commonly known as superabsorbents, are polymers which can swell up and absorb large quantities of liquid, particularly water, or also, to a lesser extent, body fluids.
They also have the particular property that they retain the fluids even under moderate pressure; owing to this characteristic, their use in absorbent elements for disposable absorbent articles has been proposed for some time.
The high absorption capacity of superabsorbents is not, however, combined with similarly rapid absorption and this may adversely affect the performance of absorbent articles incorporating these substances.
In fact, superabsorbents may give rise to a phenomenon defined in the prior art as "gel blocking"; when a particle of superabsorbent is in contact with the liquid, its external surface starts to absorb the liquid and swells up obstructing the transmission of the liquid into the particle itself; the liquid can penetrate further into the still-dry core of the particle only by means of a very slow diffusion mechanism.
This phenomenon may prevent full use being made of the large absorption capacities of superabsorbent substances.
Leaving out of consideration the type of superabsorbent material and the shapes and sizes of the particles, "gel blocking" is generally encouraged by the formation of agglomerations of superabsorbent particles within the absorbent structure, which may occur either before use, when the particles are still dry, or during use, when the particles start to absorb the liquid and swell up.
In any case, with the use of hydrogelling absorbent materials, it is possible to produce absorbent elements which contain less hydrophilic fibres for a given absorption capacity and which consequently have smaller dimensions, particularly thicknesses, than conventional absorbent elements made of fibres alone.
Structures have been formed in which the fibres and the particles of hydrogelling, absorbent material are disposed in separate, generally very thin, superposed layers.
Many particular forms of layered, absorbent structures of this type, in which the fibrous material is represented by one or more layers of wadding, absorbent paper or non-woven fabric, and in which the particles of hydrogelling absorbent material are incorporated in the structure in various ways, are known in the art.
In layered structures which are formed dry, the at least two fibrous layers are bound together solely by the intertwining of fibres and the particles of hydrogelling absorbent materi

REFERENCES:
patent: 4857065 (1989-08-01), Seal
patent: 5175046 (1992-12-01), Nguyen
patent: 5352480 (1994-10-01), Hansen et al.
patent: 5360420 (1994-11-01), Cook et al.
patent: 5387208 (1995-02-01), Ashton et al.
patent: 5589256 (1996-12-01), Hansene t al.
patent: 5599335 (1997-02-01), Goldman et al.
patent: 5607414 (1997-03-01), Richards et al.
patent: 5653702 (1997-08-01), Brohammer et al.

Affiliated with

Also associated with

Rating

Layered, absorbent structure, an absorbent article comprising th does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Layered, absorbent structure, an absorbent article comprising th, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Layered, absorbent structure, an absorbent article comprising th will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-2425051