CA2159784C - Method and apparatus for manufacturing a liquid-absorbent article and the resulting product thereof - Google Patents

Abstract

Method and apparatus of manufacturing a liquid-absorbent article by deposition of particles suspended in fluid on a forming member under the influence of a pressure differential. The liquid-absorbent article is suitable for use as an absorbent component of a disposable absorbent product such as a sanitary napkin, a diaper, a urinary pad, an adult brief, a nursing pad, a tampon pledget and a desiccant for keeping goods dry during shipping and storage, among others. The method allows to produce anatomically shaped liquid-absorbent articles that better fit the perineal region of the wearer, and/or having a non-uniform thickness for improved absorption at selected areas. The invention also extends to a liquid-absorbent article produced by the aforementioned method.

Description

21~ X784 Docket No. CAN-65 TITLE: METHOD AND APPARATUS FOR MANUFACTURING A LIQUID-AHSORHENT ARTICLE AND THE RESULTING PRODUCT
'THEREOF
FIELD OF THE INVENTION
The present invention relates to the art of manufacturing structures for absorbing body exudate. More particularly, the invention relates to a method and apparatus for manufacturing liquid-absorbent articles by deposition of particles suspended in fluid on a foraminous forming member. Advantageously, the method can be used for producing anatomically shaped, non-planar liquid absorbent components for disposable absorbent products such as sanitary napkins, diapers, urinary pads, adult briefs, nursing pads, tampon pledgets and desiccants for keeping goods dry during shipping and storage, among others.
BACKGROUND OF THE INVENTION
Traditionally, sanitary napkins for medium to high menstrual flow have been relatively thick and bulky containing an absorbent core made of fluffed hydrophillic materials such as wood pulp, rayon or cotton. These absorbent materials are attractive because they are fairly ~~.~ 9'~8~
Docket No. CAN-65 easy to manufacture at low cost while having, at least theoretically, a high absorbent capacity. However, this category of disposable absorbent products is known to possess severe deficiencies, failing in practise to provide the required protection against leakage and staining. More particularly, such fibrous materials suffer from poor fluid distribution properties and do not have the ability to disperse fluid within the entire available absorbent volume. As a result, the absorbed fluid will tend to concentrate in a certain area of the absorbent core, causing localized saturation and collapse.
This phenomenon often results in fluid leaking past the edges of the sanitary napkin and staining the wearer's clothes. Another disadvantage of sanitary napkins with thick absorbent cores resides in their inability to closely conform and follow the contour of the human body, achieving at best an intermittent contact surface between the fluid permeable side of the sanitary napkin and the integument of the wearer, which results in poor gasketing, increasing the likelihood of failures due to fluid leakage.
To address the above-discussed problems, a growing number of thinner and more flexible sanitary napkins have been developed, providing better fit, comfort and discretion, while being sufficiently absorbent to provide Docket No. CAN-65 effective menstrual protection. The absorbent cores used in thin sanitary napkins include compressed sphagnum moss material which has a large proportion of extremely tiny pores and capillaries, having the ability to absorb a very high quantity of liquid.
The following United States patents document the use of sphagnum moss material for manufacturing absorbent components for disposable absorbent products.
PATENT INVENTOR(sj DATE OF ISSUE
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4,170,515 Lalancette et al. October 9, 1979 4,215,692 Levesque August 5, 1980 4,226,237 Levesque October 7, 1980 4,305,393 Nguyen December 15, 1981 4,473,440 Ovans September 25, 1984 4,507,122 Levesque March 26, 1985 4,618,496 Brasseur October 21, 1986 4,676,871 Cadieux et al. June 30, 1987 4,992,324 Dubs February 12, 1991 5,053,029 Yang October 1, 1991 I I I I

215~7~4 Docket No. CAN-65 Sphagnum moss material can be formed in a highly cohesive sheet by using anyone of the methods disclosed in the above-identified prior art. In sheet form, the sphagnum moss material is convenient to handle and it can be directly processed in high speed automatic equipment for assembling disposable absorbent products.
More particularly, the method for producing the sphagnum moss sheet consists of wet classifying raw peat moss material in particulate form to retain only the particles which are the most absorbent. The screened fraction is sheeted on a Fourdrinier wire in the form of a slurry and de-watered by the application of vacuum. The thus formed sheet is dried and calendered to increase its density to the desired level. In order to tenderize, soften and improve the flexibility of the calendered sphagnum moss sheet, it may be subjected to mechanical working such as perf-embossing or micro-corrugating as described in the United States patents 4,559,050 and 4,596,567 to Iskra issued on December 17, 1985 and June 24, 1986 respectively.
-~ 4 Docket No. CAN-65 The sphagnum moss sheets manufactured by the above-described wet laying method have a planar configuration.
Although such liquid-absorbent sheets possess a high degree of fly=_xibi.lity and softness, hence they are highly conforrr,able to the shape of the human anatomy, there are lirnits to the degree of deformation the absorbent structure can sustain. For that reason, it is desirable to develop a method and an apparatus allowing to manufacture sphagnum moss liquid-absorbent articles having either a planar or a non-planar configuration, as desired.
OHJECTB AND BT;i~TEMENT OP TH8 INVENTION
An object of this invention is to provide an improved method for manufacturing a liquid-absorbent article from particles susF~ended in fluid (for the purpose of this specification '"particle" means a small amount of material without limitations of shape. A fiber that is characterized by a geometrical extension along a preferential dlirect:ion will be considered a particle.
Hence, "partic:ulate matter" covers a material made of fibers, particles having non-fibrous identity or a combination of both).
Another olbject of the invention is an apparatus for carrying aut the aforementioned method.

Docket No. CAN-65 A further object of the invention is a fluid-laid liquid-absorbent article of non-planar configuration. For the purpose of this specification, the expression "non-planar configuration" is intended to encompass three-s dimensional shapes that are not flat, such as convex or concave bodies, or shapes which have of non-uniform thickness. An example of the later case is a sheet-like absorbent core with thinner marginal portions by comparison to its central area. Although the sheet-like absorbent core may have a preferential extension along an imaginary plane, it is considered non-planar because at least one of its main outer surfaces is not confined within a plane. In contrast, a sheet-like body having parallel main faces will be characterized as planar.
As embodied and broadly described herein, the invention provides a method for manufacturing a liquid-absorbent article, said method comprising the steps of:
- placing a foraminous forming member in a body of particles suspended in a fluid, such as liquid or gas;
- establishing a pressure differential across said forming member to cause particles in said fluid to agglomerate on said forming member into a layer of particles;
- removing said layer of particles from said forming member to form said liquid-absorbent article.

~1~~~~4 Docket No. CAN-65 This method is particularly well-suited for manufacturing absorbent cores made from sphagnum moss material, although other particulate materials can be used as well. In a preferred embodiment, raw sphagnum moss is wet-classified to remove the particles that are substantially non-absorbent, such as the extremely small particles commonly referred to as fines, and larger rejects such as roots and branches. The classified fraction is then formed into an aqueous slurry having a consistency in the range from about 0.1% to about 3.0%
solids, preferably of about 1.0%. The forming member is an apertured surface in fluid communication with a suction device. When the forming member is immersed in the slurry of sphagnum moss particles and the suction device is actuated, the resulting pressure differential causes sphagnum moss particles to agglomerate on the surface of the forming member into a layer of complimentary shape.
Thus, by employing a concave forming member, a cup-shaped liquid-absorbent article will be produced. Such shape enables the absorbent article conform well to the perineal region of the human body.
The thickness of the sphagnum moss layer deposited on the forming member is determined by the residence time of the forming member in the liquid suspension and also by the intensity of the pressure differential. Generally _ -Docket No. CAN-65 speaking, an increased pressure differential will result into a thicker layer of sphagnum moss. Likewise, a longer residence time in the liquid suspension produces a thicker deposit.
The present method can be put to practical use for manufacturing tampon pledgets by employing mandrel-shaped forming members. In one embodiment, a layer of particulate material, preferably sphagnum moss, is caused to agglomerate on the outer surface of the forming member, ' thus producing a hollow pellet-like mass which can be deposited in the vaginal orifice of the user by conventional tampon applicator structures. In a variant, the particle agglomeration is effected within the cavity of a forming member to provide a solid pellet-like tampon pledget.
The method according to the invention also allows to manufacture laminated liquid-absorbent articles by successively depositing on the forming member layers from different particle suspension beds. Each layer of particles forms an individual stratum of the absorbent structure. For instance, if a dual-layer structure is contemplated, the forming member is first immersed in a first particle suspension to build-up the first layer and then transferred to a second particle suspension to form .. 8.

2.~ ~ 9'~ ~~
Docket No. CAN-65 the second layer on top of the first layer. This feature enables to produce tampon pledgets, either hollow or of the solid variety, having an outer liquid-permeable jacket that prevents fragmentation and loss of structural integrity of the inner sphagnum moss core during use of the tampon pledget. Such protective jacket is preferably build-up by deposition of comparatively long fibers made of polyester, rayon, cotton or cellulose, among other materials.
The method in accordance with the invention also offers the possibility of manufacturing liquid-absorbent articles of varying thickness. In one embodiment, this is achieved by establishing a pressure differential gradient along the surface of the forming member. For instance, the apertures establishing a fluid path with the source of vacuum are made comparatively large at the areas of the forming member where a high rate of particle deposition is required. In contrast, smaller apertures are formed in the areas where a reduced thickness is desired. It will be apparent that the smaller apertures create a path of higher resistance to fluid drawn by the source of vacuum and as a consequence the forces that urge the particles in suspension to agglomerate against the forming member are weaker in that region.
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Docket No. CAN-65 As embodied and broadly described herein, the invention also provides an apparatus for manufacturing a liquid-absorbent article, said apparatus comprising:
- a container for holding a suspension of particles in a fluid; _ - suction means;
- a forming member capable of insertion in said container, said forming member having an apertured surface in a fluid-communicative relationship with said suction means, whereby said suction means is capable of establishing across said apertured surface a pressure differential for causing deposition of particles in said suspension against said apertured surface in order to form said liquid-absorbent article.
As embodied and broadly described herein the invention also provides a moulded, non-planar, liquid absorbent article, said liquid-absorbent article comprising discrete particles amalgamated into a unitary structure, said particles forming interstices therebetween for admitting liquid.
As embodied and broadly described herein, the invention further provides a laminated, integral, tampon pledget comprising:

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Docket No. CAN-65 - an absorbent core comprising discrete particles amalgamated into a unitary structure, said particles forming interstices therebetween for admitting liquid; and - a jacket of fibrous material covering at least partially said absorbent core, said jacket having a three-dimensional structure complementary to said absorbent core and being joined therewith in an intimate fluid-communicative relationship, whereby body exudate delivered to said jacket of fibrous material is capable of migrating through said jacket toward said absorbent core.
BRIEF DESCRIPTION OF TH$ DRAWINGS
- Figure 1 is a schematic representation of an apparatus according to the invention for manufacturing a liquid-absorbent article, showing a forming member immersed in a suspension of particles at the beginning of a liquid aspiration cycle;
- Figure 2 illustrates the apparatus of Figure 1, showing a build-up of particles on the forming member following a period of aspiration of liquid;
- Figure 3 illustrates the forming member withdrawn from the suspension following completion of the formation of a layer of particles on the forming member;
- il -21~~'~8 Docket No. CAN-65 - Figure 4 illustrates the forming member located in a station for drying the formed layer of particles;
- Figure 5 illustrates the forming member located in a station for treating the formed layer of particles with binder;
- Figure 6 illustrates the forming member in the process of ejecting the dried liquid-absorbent article;
- Figure 7 shows a variant of the forming member featuring a non-planar configuration;
- Figure 8 is a plan view of a forming member in accordance with a variant characterized by the ability of producing a liquid-absorbent article having a non-uniform thickness;
- Figure 8a is a vertical cross-sectional view of forming member in accordance with a further variant employing a dual source of vacuum for producing a liquid-absorbent article having a non-uniform thickness.
- Figure 9 is a vertical sectional view of a mandrel-shaped forming member for use in manufacturing tampon pledgets in accordance with the invention;

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Docket No. CAN-65 - Figure 10 illustrates the mandrel-shaped forming member partially immersed in a first liquid suspension while aspiration is being applied to build-up the absorbent core of the pledget;
- Figure 11 illustrates the build-up of particles against the mandrel-shaped forming member after a period of time following the actuation of the suction device; and - Figure 12 illustrates the mandrel-shaped forming member partially immersed in a second liquid suspension to form an outer protective jacket on the previously formed absorbent core;
- Figure 12a is a vertical cross-sectional view of a dual-layer tampon pledget to which is integrated a loop-shaped withdrawal string;
- Figure 13 is a vertical cross-sectional view of a forming member in accordance with a variant for producing a solid core tampon pledget;
- Figure 14 illustrates the forming member shown in Figure 13 immersed in a liquid suspension to form the outer protective jacket of the tampon pledget;

Docket No. CAN-65 - Figure 15 is a vertical cross-sectional view of the forming member of Figure 13, showing the formed protective jacket and a withdrawal string;
- Figure 16 illustrates the forming member with the protective jacket and the withdrawal string immersed in a liquid suspension to form the absorbent core of the tampon pledget;
- Figure 17 illustrates the forming member immersed in an another liquid-suspension to completely close the protective jacket, thus encapsulating the absorbent core;
and - Figure 18 is a vertical cross-sectional view of the formed tampon pledget.
DESCRIPTION OF PREFERRED EKHODIMENTB
Figure 1 of the annexed drawings schematically illustrates an apparatus 10 for manufacturing liquid-absorbent articles by deposition of solid particles suspended in a liquid. More specifically, the apparatus 10 comprises a vessel 12 containing an aqueous slurry of solid particles from which the absorbent article will be made. In a specific example, the solid particles are 2~~97~4 Docket No. CAN-65 sphagnum moss. However, other materials can also be used such as polyester fibers, rayon fibers, cotton fibers, and cellulose fibers, among many others.
The suspension of sphagnum moss particles has a consistency in the range from about 0.1% to about 3.0% by weight of solids and most preferably of about 1.0%.
A forming member 14 is shown immersed in the suspension of sphagnum moss particles. The forming member 14 comprises a container member 16 in which is mounted a fine mesh screen 18. The container member 16 has an opened lower extremity and an upper extremity (as viewed in the drawings) that is closed except for an opening communicating with a conduit 20. The screen 18 is maintained in the container member 16 to separate the container member 16 into a first portion adjoining the opened lower extremity and a second portion between the upper extremity and the screen 18.
The conduit 20 is connected to a source of vacuum such as a pump (not shown in the drawings). When the pump is energized, a pressure differential is established across the screen 18 (i.e. the pressure in the first portion that adjoins the open end of the container member 16 is higher than the pressure in the second portion - _l5 -between the screen 18 and the upper end of the container member lE~) which causes aspiration of water through the conduit 2Ø Solid particles of the suspension that are entrained in the flow are arrested by the screen 18 and agglomerate, as shown in Figure 2, into a layer of uniform thickness. The particles, when agglomerating, thereby also forming interstices for admitting liquid.
The layer of sphagnum moss particles is designated by the reference 22.. The rate of material build-up is determined primarily by the intensity of the pressure differential ~icro~;s the screen 18. Generally, increased vacuum will produce a higher rate of material deposition on the screen 18. Of course, the final thickness of the layer 22 is detE=_rmined by the rate of material deposition anti al=;o by the residence time of the forming member 14 in the su:~pension oi. sphagnum moss particles.
Once the desired sphagnum moss thickness has been reached, the forming member 14 is withdrawn from the vessel 12. This can be achieved by mounting the forming member 16 to a hydraulic or pneumatic actuator (not shown in the drawings) to displace the forming member 14 in and out oi= the vessel 12 in order to automate the manufacturing process. It will be appreciated that a flexible line (not. ahown in the drawings) ~is required to connect the c~~ndu:it 20 to the source of vacuum that is preferably a ~;tationary installation.

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Docket No. CAN-65 When the forming member 14 is withdrawn from the suspension of sphagnum moss particles, it is desirable to maintain the pressure differential so as to avoid the layer of sphagnum moss particles from falling under the effect of gravity.
At the next processing stage, as shown in Figure 4, the forming member 14 is placed in a body of warm air such as an oven 26. By maintaining the aspiration through the conduit 20, warm air passes through the particulate layer 22 and causes water to evaporate. This stage is a convenient location for treating the sphagnum moss layer with the desired substance to impart to it desirable properties. For example, as shown in Figure 5, the sphagnum moss material may be treated with a binder substance by vaporizing in the oven 26 liquid binder from nozzle 24 to create a suspension of droplets that are drawn within the layer 22 during the drying phase. In addition to causing the binder droplets to penetrate deeply within the sphagnum moss material, the air flow also accelerates the curing time of the binder.
Treatments other than binder deposition can also be envisaged, such as delivery of surfactant to better develop the affinity of the sphagnum material for water, among others.

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Docket No. CAN-65 Once the drying/curing stage has been completed, the layer 22 is ejected from the forming member 14 by reversing the pressure differential. This is accomplished by switching the vacuum source to the air blowing mode, as shown in Figure 6.
In a variant, the apparatus 10 may be used to manufacture multi-layered absorbent articles. This is achieved by providing several vessels containing a suspension of different particles that form the various layers of the final structure. By successively performing an aspiration cycle in each vessel, a laminated structure can be built-up. Of course, the various layers would have to have sufficient porosity to permit liquid containing the particles for the final layer to be admitted through the base layers under the effect of the pressure differential so that particles can be deposited on the base layers.
Figure 7 illustrates a variant of the forming member.
The difference with the previously described embodiment resides in the shape of the screen 18 which has a non-planar configuration. This is a particularly desirable feature because it allows to manufacture sphagnum moss articles of a specific shape selected to fit well the anatomy of the user. For instance, the arrangement of 21~~~~
Docket No. CAN-65 Figure 7 would allow to produce a cup-shaped sphagnum moss layer that conforms to the perineal area of the user.
Such cup-shaped absorbent structures could be advantageous for use as absorbent cores in sanitary napkins or urinary pads.
In a further variant shown in Figure 8, the screen 18' is constituted by a wire mesh so arranged as to create comparatively small openings near the longitudinal end edges of the forming member and much larger openings in the centre. It will be apparent to those skilled in the art that the small openings would create a path of high resistance to fluid aspirated by the conduit and, as a result, the forces urging the particles against the screen 18' are more intense in the centre than at the longitudinal extremities. Consequently, the final layer will be thicker at the centre than at the ends. This feature enables to produce liquid absorbent articles that are thicker at selected areas where high absorbency is required. In a variant, as shown in Figure 8a, a non-uniform rate of material deposition is achieved by connecting selected zones of the forming member where a thicker deposit is required to a source of high vacuum, while the remaining of the forming member is subjected to lower vacuum. In the drawing, the central portion of the forming member 18 " is coupled to a first aspiration conduit 19 that i_s connected to a source of high vacuum (not shown :W the drawings). On the other hand, the peripheral portion of the forming member 18" is subjected to a lower pressure deferential established by a second conduit 21 leading to a source of lower vacuum (not shown in the drawings). It will be apparent that the resu.ltinc~ la~~er of sphagnum moss will be thicker at the center than at the sides.
Advantageously, the present invention can also be used for manufacturing single layered or multi-layered tampon pledgets, a:~ shown in Figures 9 to 18. Figure 9 illustrates a f:~rming member 28 on which a tampon pledget is build-up. The forming member 28 is a hollow, mandrel-shape stz~u~~ture having a foraminous surface 30 that covers a portion of its length. The internal cavity of the forming member 28 is coupled to the source of vacuum (not ~~hown in the drawings) to create the pressure diff'eren.tial across the foraminous surface 30.
In Figure 10, the forming member 28 is shown partially immersed in a liquid suspension of sphagnum moss particles to force the absorbent core 32 of the tampon pledget. The particles, when agglomerating, thereby also foaming interstices for admitting liquid. As mentioned ea:=liei:~, the residence time of the forming member 28 in the liquid suspension and the intensity of the aspiration a:Llow the operator to control the thickness of the core 32 for, in turn, controlling its absorption capacity.

Docket No. CAN-65 Once the desired core thickness has been reached, the forming member 28 is transferred to a vessel, as shown in Figure 12, containing long fibers suspended in water in order to form on the sphagnum moss absorbent core a protective jacket 34 to prevent fragmentation and loss of structural integrity of the absorbent core 32 in use. In a preferred embodiment, the liquid suspension contains fibers of a length in the range from about 1 cm to about 3 cm and has a consistency in the range from about 0.1% to about 5.0% by weight of solids, more preferably of about 2.0%. The fibers are preferably selected from the group consisting of polyester, rayon, cotton and cellulose, among many others.
Since the jacket 34 is directly moulded by successive fiber deposition on the absorbent core 32, it acquires a three-dimensional shape complementary to the configuration of the absorbent core 32. As a result, the absorbent core 32 is enclosed within a fibrous network that facilitates the insertion of the tampon pledget in the vaginal orifice of the user, and also prevents the sphagnum moss particles from loosening and falling off the tampon pledget, especially when the absorbent structure is saturated with liquid.
- 2i -Docket No. CAN-65 When subjected to a liquid discharge, the protective jacket 34 behaves as a transit region that initially captures the liquid before passing it to the absorbent core where it is permanently entrapped. As a consequence, the porosity of the protective jacket 34, and the nature of the bond absorbent core/jacket are important factors that influence the liquid-absorptive properties of the tampon pledget structure. Most preferably, the protective jacket 34 should have a comparatively high inter-fiber void volume to provide a high liquid acceptance rate.
Fibrous material selected from the group of polyester, rayon, cotton and cellulose yields a porous network having the desired properties in this regard. In addition, since the jacket 34 is build directly over the absorbent core 32, these components are structurally united in an intimate fluid communicative relationship, that enables a fast fluid transfer from the jacket toward the core.
In a variant, a withdrawal string 36 may be integrated to the tampon pledget structure, as shown in Figure 12. This is achieved by positioning alongside the absorbent core 32, prior the deposition of the protective jacket 34, the withdrawal string 36. The string should be long enough to sufficiently extend beyond the upper boundary of the foraminous surface 30 so as to enable the user.to conveniently grasp it when the tampon pledget is 21~9'~04 Docket Ho. CAH-65 inserted in the vaginal orifice. It will become apparent that during the deposition of the fibrous material the withdrawal string 36 becomes gradually integrated to the protective jacket 34. To prevent the string from being accidentally extracted from the fibrous mass forming the protective jacket 34, one or more anchoring projections, such as knots, may be provided on the string.
Alternatively, the string may be formed into a loop, as shown in Figure 12a.
After the protective jacket 34 is formed on the absorbent core 32, the mandrel-shaped forming member 28 is withdrawn from the liquid suspension and it is then subjected to the desired post-formation treatments such as drying, binder deposition and hydrophilicity enhancement, among others. Finally, the tampon pledget is extracted from the mandrel-shaped forming member 28 by effecting a pressure differential reversal, as discussed in connection with the previous embodiment. It will be noted that once the tampon pledget has been striped from the mandrel-shaped forming member 28, a cavity remains in the absorbent core 32. This cavity should be small, otherwise the structural integrity of the tampon pledget may be compromised. For this reason, a forming member having the smallest possible diameter should be used.

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Docket No. CAN-65 The method in accordance with the invention can also be used for manufacturing solid-core tampon pledgets, as shown in Figures 13 to 17. The forming member 38, best illustrated in Figure 13, is in the form of a blind sleeve having a solid outer wall 40 and an internal cylindrical cavity 42. The cavity 42 is delimited by a foraminous surface, such as fine wire mesh which is radially spaced apart from the outer wall 40 to define a surrounding fluid passage that merges with a conduit 46 that is connected to the source of vacuum (not shown in the drawings).
The tampon pledget formation process consists of first aspirating fibers suspended in liquid to partially build-up an outer protective jacket 48, as shown in Figures 14 and 15. The forming member 38 is then removed from the liquid suspension and a withdrawal string 50 inserted in the cavity of the protective jacket 48.
Preferably, the string is in the form of a loop which is temporarily retained to the fibrous material of the protective jacket 48 by a small amount of positioning adhesive so, the free ends of the loop are left hanging from the forming member. Next, the assembly is immersed in the liquid suspension of sphagnum moss to form the absorbent core 52 of the tampon pledget, as shown in Figure 16. Contrary to the previous embodiment, the core is solid and free of cavities. Finally, the assembly is Docket No. CAN-65 immersed in a liquid suspension of long fibers (the same fibers used for making the protective jacket 48) , as shown in Figure 17 to form a layer 54 that fully closes the protective jacket around the absorbent core 52 for a complete encapsulation. For ease of use, the free ends of the withdrawal string structure can be tied into a knot, as depicted in Figure 18.
The above description of this invention should not be interpreted in any limiting manner since many variations and refinements are possible without departing from the spirit of the invention. The scope of the invention is defined in the annexed claims and their equivalents.

Claims (31)

1. A method for manufacturing a liquid-absorbent article, said method comprising the steps of:
- placing a foraminous forming member in a body of particles suspended in fluid;
- establishing a pressure differential across said forming member to cause particles in said fluid to agglomerate on said forming member into a layer of particles;
- removing said layer of particles from said forming member to form said liquid-absorbent article.

2. A method as defined in claim 1, comprising the step of drying said layer of particles.

3. A method as defined in claim 1, comprising the step of drying said layer of particles prior to removing said layer or particles from said forming member.

4. A method as defined in claim 1, comprising the step of placing said forming member with said layer of particles thereon in a body of warm gas and establishing a pressure differential across said layer of particles to cause said warm gas to flow through said layer of particles in order to dry said layer of particles at least partially.

5. A method as defined in claim 1, comprising the steps of:
- placing said forming member in a first body of particles suspended in fluid;
- establishing a pressure differential across said forming member to build-up a first layer of particles on said forming member;
- placing said forming member with said first layer of particles in a second body of particles suspended in fluid;
- establishing a pressure differential across said first layer of particles to deposit thereon a second layer of particles, thereby forming a laminated liquid-absorbent article.

6. A method as defined in claim 1, comprising the step of establishing a non-uniform pressure differential along said forming member to cause particles to deposit at a non-uniform rate on said forming member, thereby forming a liquid-absorbent structure having a non-uniform thickness.

7. A method as defined in claim 1, wherein said particles are sphagnum moss particles.

8. A liquid-absorbent article manufactured by the method of claim 1.

9. A liquid-absorbent article as defined in claim 8, wherein said liquid-absorbent article is an absorbent component of a disposable absorbent product selected in the group consisting of sanitary napkin, diaper, urinary pad, adult brief, nursing pad, tampon pledget and a desiccant for keeping goods dry during shipping and storage.

10. An apparatus for manufacturing a liquid-absorbent article, said apparatus comprising:
- a container for holding a body of particles suspended in fluid;
- suction means;
- a forming member capable of insertion in said container, said forming member having a foraminous surface in a fluid-communicative relationship with said suction means, whereby said suction means is capable of establishing across said foraminous surface a pressure differential for causing deposition of particles in said fluid against said foraminous surface in order to form said liquid-absorbent article.

11. An apparatus as defined in claim 10, wherein said forming member has a non-planar configuration.

12. An apparatus as defined in claim 11, wherein said foraminous surface is cup-shaped.

13. An apparatus as defined in claim 11, wherein said forming member has a mandrel-shape, whereby allowing to form an absorbent component for insertion in a vaginal cavity, by progressive particle deposition around said forming member.

14. An apparatus as defined in claim 11, wherein said forming member forms a cavity, whereby allowing to form an absorbent component for insertion in a vaginal cavity, by progressive particle deposition within said cavity.

15. An apparatus as defined in claim 10, comprising means for establishing a non-uniform pressure differential along said foraminous surface to cause a non-uniform particle deposition thereon.

16. An apparatus as defined in claim 15, wherein said means for establishing a non-uniform pressure differential along said foraminous surface comprises openings of variable size on said foraminous surface.

17. An apparatus as defined in claim 15, comprising:
- a first suction means in a fluid communicative relationship with a first region of said foraminous surface;
- a second suction means in a fluid-communicative relationship with a second region of said foraminous surface, said first suction means developing a higher pressure differential than said second suction means, whereby causing a higher rate of particle deposition on said first region than on said second region.

18. An apparatus as defined in claim 10, comprising means for generating warm gas for aspiration through said liquid-absorbent article in order to dry said liquid-absorbent article.

19. An apparatus as defined in claim 10, comprising means for establishing a positive pressure differential across said liquid-absorbent article for ejecting said liquid-absorbent article from said forming member.

20. A moulded, non-planar, liquid absorbent article, said liquid-absorbent article comprising discrete particles amalgamated into a unitary structure, said particles forming interstices therebetween for admitting liquid.

21. A moulded liquid-absorbent article as defined in claim 20, wherein said liquid-absorbent article has a laminated structure.

22. A moulded liquid-absorbent article as defined in claim 20, comprising sphagnum moss.

23. A moulded liquid-absorbent article as defined in claim 20, wherein said liquid-absorbent article is an absorbent component of a disposable absorbent product selected in the group consisting of sanitary napkin, diaper, urinary pad, adult brief, nursing pad, tampon pledget and a desiccant for keeping goods dry during shipping and storage.

24. A moulded liquid-absorbent article as defined in claim 20, wherein said liquid-absorbent article has a cup-shaped configuration.

25. A moulded liquid-absorbent article as defined in claim 20, wherein said liquid-absorbent article has a non-uniform thickness.

26. A laminated, integral, tampon pledget comprising:
- an absorbent core including discrete particles amalgamated into a unitary structure, said particles forming interstices therebetween for admitting liquid; and - a jacket of fibrous material covering at least partially said absorbent core, said jacket having a three-dimensional structure complementary to said absorbent core and being joined therewith in an intimate fluid-communicative relationship, whereby body exudate delivered to said jacket of fibrous material is capable of migrating through said jacket toward said absorbent core.

27. A tampon pledget as defined in claim 26, wherein said absorbent core includes sphagnum moss.

28. A tampon pledget as defined in claim 26, comprising a withdrawal member for extracting said tampon pledget from a vaginal opening.

29. A tampon pledget as defined in claim 26, wherein said absorbent core is hollow.

30. A tampon pledget as defined in claim 26, wherein said absorbent core is substantially free of internal cavities.

31. A tampon pledget as defined in claim 26, wherein said jacket of fibrous material totally encapsulates said absorbent core.