Absorbent peat moss board product

A disposable absorbent product, such as a urinary pad, comprises a liquid-impermeable, substantially flexible shell, an absorbent core and a liquid permeable facing adhered to the shell so as to enclose the absorbent core therein. The absorbent core comprises at least one layer of tenderized peat moss, each such layer being cut adjacent to each lengthwise edge in one or more slits so as to aid lateral compression folding of the sheet, and, adjacent to the layer of peat moss, a receiving layer of an absorbent cellulosic material. The absorbent core has an M-fold configuration and comprises a longitudinally extending channel for receiving discharged liquid.

BACKGROUND OF THE INVENTION 
The present invention relates to a new and improved disposable absorbent 
products such as a urinary pad having high liquid impact capacity, high 
liquid retention, and which allows the skin of the wearer to remain dry. 
Disposable absorbent products have been known for some time, including such 
products as disposable diapers, sanitary napkins, wound dressings, 
bandages, incontinent pads, and the like. These products incorporate an 
absorbent batt which is used to absorb and hold or contain body fluids. 
Initially in many of these products, especially diapers and sanitary 
napkins, the absorbent batt comprised what is termed "wadding" or plies of 
tissue. The wadding was disposed between a liquid-impermeable backing and 
a liquid-permeable facing and the plies of tissue were used to absorb and, 
hopefully, contain the liquid within the product. A diaper which utilizes 
such an absorbent batt is disclosed in U.S. Pat. No. Re. 26,151. 
The wadding type of product was replaced, for the most part, by an improved 
absorbent batt which comprises what is termed "fluffed wood pulp fibers". 
This absorbent batt comprises a layer of individualized wood pulp fibers 
with the layer having substantial thickness. A diaper which incorporates 
such fluffed wood pulp absorbent batt is described in U.S. Pat. No. 
2,788,003. This diaper had improved absorbent capacity and somewhat better 
containment than a diaper using a wadding layer. Also, the fluffed wood 
pulp layer is quite soft, flexible, and conformable, and, hence, produces 
an improved diaper over diapers using wadding as the absorbent layer. 
Although fluffed wood pulp absorbent batts have a good absorptive capacity, 
the efficiency with which the capacity is used in a diaper or sanitary 
napkin is poor. The reason for this is that the fluid to be absorbed is 
generally deposited in a localized area within the absorbent batt, and the 
ability of the fluid to move along the plane of the batt is poor. The 
fluid tends to follow a radial wicking path and consequently moves to the 
closest edge of the batt where it generally is no longer contained and the 
product leaks. 
In designing a disposable urinary device, one must be mindful of the 
special problems of an incontinent adult. First, the void of an adult 
generally is much higher in volume than that of an infant, so a device 
with greater absorptive capacity than that of an infant's diaper is 
needed. Second, a bulge under clothing is accepted by society for an 
infant, but the ambulatory adult with an incontinence problem longs for a 
product which is not visible through ordinary clothing. Third, the 
proportions and shape of the legs and torso of the adult differ 
considerably from those of an infant. Therefore, a mere enlargement of an 
infant diaper is not a satisfactory product. 
A number of years ago, "superabsorbent materials", i.e., materials which 
will absorb many times their weight of liquid, were developed. Since the 
development of such materials, attempts to incorporate them in absorbent 
products such as diapers to enhance the absorption performance of these 
products have been made. Theoretically, a minimum amount of superabsorbent 
incorporated in a product would make that product perform as well or 
better than the prior art products. Perhaps one of the first products to 
incorporate such a superabsorbent material in a disposable diaper is 
disclosed in U.S. Pat. No. 3,670,731. This patent discloses an absorbent 
dressing comprising an absorbent layer sandwiched between a permeable 
facing and an impermeable backing sheet. The absorbent layer contains 
water-insoluble cross-linked hydrocolloid polymer as the superabsorbent 
material. 
For numerous reasons, absorbent products employing superabsorbent materials 
as mentioned above have not to date met with great commercial success. 
Although the presence of the superabsorbent materials should greatly 
increase the absorbency of the product, difficulties in processing the 
materials and in designing a product in which the superabsorbent is evenly 
dispersed have proven difficult. There thus remains a need for highly 
absorbent materials which do not pose these problems. 
The use of peat moss, in combination with other fibrous materials, for use 
in absorbent products has previously been suggested. U.S. Pat. No. 
4,170,515 to J-M Lalancette discloses a method for bleaching peat moss, 
thereby making it suitable for use in absorbent dressings and the like. 
U.S. Pat. No. 4,226,237 to Y. Levesque discloses a layered absorbent 
structure including a first layer comprising cellulose fibers and, 
adjacent to the first layer, a second layer comprising, in admixture, peat 
moss and finely ground mechanical wood pulp. U.S. Pat. Nos. 4,215,692 and 
4,507,122, both issued to Levesque, disclose that peat moss, in 
combination with mechanical wood pulp, can be formed into a low density 
board, dried, and then compressed to form a thin, flexible, absorbent 
board which may be used directly in absorbent products. U.S. Pat. No. 
4,473,440 to Ovans discloses a peat moss containing board which is 
manufactured by first conditioning the board to a specific water content 
and then densifying the board by calendaring between rollers. U.S. Pat. 
No. 4,676,871 discloses an air laid peat moss board suitable for use in 
absorbent products which is made by harvesting and individualizing peat 
moss, drying the peat moss, entraining the peat moss in a gas stream, and 
then condensing the entrained peat moss to form a low density board. The 
disclosures of each of these patents are herein incorporated by reference. 
Numerous designs for disposable urinary devices have been suggested, none 
of which, however, utilize a peat moss absorbent element. U.S. Pat. No. 
4,685,914 discloses a disposable urinary pad which utilizes superabsorbent 
material. The pad disclosed in this patent comprises a liquid-impermeable, 
substantially flexible shell containing a superstructure consisting 
essentially of a fibrous web of hydrophobic, wet resilient, dry resilient 
fibers and an absorbent medium in intimate contact with at least a portion 
of said superstructure and at least a portion of said shell. In a 
preferred embodiment, the superstructure is a corrugated fibrous web, 
e.g., of polyester fibers, and the absorbent medium is a superabsorbent 
material. 
U.S. Pat. No. 4,501,586 discloses an absorbent structure comprising a 
moisture-impermeable backing, an absorbent batt and a moisture-permeable 
cover covering at least the side opposite the moisture-impermeable 
backing. The absorbent batt is of loosely-compacted, cellulosic fibers and 
is provided with a reservoir having a capacity of at least 10 cc. The 
reservoir is formed by compression of the fibers in the reservoir zone and 
is located so that the product, when worn, retains the proper shape. 
U.S. Pat. No. 4,731,070 discloses an absorbent article particularly 
suitable for use by male and female incontinents. The absorbent article 
includes a urine receptacle pocket offset to one end of the product and 
formed by folding the product and adhering together portions of a moisture 
impervious sheet that are folded over side marginal edges of an absorbent 
batt. 
The present invention provides a new and improved absorbent product which 
possesses a large storage capacity, which is soft and comfortable, which 
can be designed so as not to be apparent through normal clothing and which 
utilizes the substantial absorptive capacity of peat moss materials. 
SUMMARY OF THE INVENTION 
The present invention relates to a disposable absorbent product, such as a 
urinary pad, which comprises a liquid-impermeable, substantially flexible 
shell, an absorbent core and a liquid-permeable facing adhered to said 
liquid-impermeable shell, so as to entrap the absorbent core therebetween. 
The liquid-impermeable shell is formed from a moldable substance. For 
example, the shell may be a polyethylene foam shell which is formed from a 
blown polyethylene foam sheet, subsequently subjected to molding by a 
thermal process. 
The absorbent core includes at least one sheet of tenderized peat moss 
product. The sheet is generally cut in a rectangular or "racetrack" shape 
and, to aid lateral compression folding of the sheet, it has been cut to 
form one or more slits adjacent to each lengthwise edge. The absorbent 
core also includes, adjacent to the sheet of tenderized peat moss product 
and disposed upwardly so as to face the wearer of the absorbent product, a 
receiving layer of an absorbent material. The receiving layer is generally 
formed of a material which is capable of absorbing body fluid more rapidly 
than would the peat moss product, but which does not exhibit the overall 
absorptive capacity of the peat moss product. The receiving layer 
therefore operates to "receive" and hold the body fluid until it is 
absorbed by the peat moss product adjacent to it. Preferably, the 
receiving layer should be capable of absorbing about 120 cc, the volume of 
a typical adult void. The receiving layer preferably comprises a fibrous 
web of both wood pulp fibers and non-cellulosic synthetic fibers, e.g., 
about 50 to 95 weight percent wood pulp and about 5 to 50 weight percent 
non-cellulosic synthetic fibers. 
The absorbent core is pleated in an M-configuration to form therein a 
center channel in a lengthwise direction. As a result of the pleating, the 
receiving layer extends down the sides of the pleated core so as to 
provide a liquid path to the bottom of the core. The pleated absorbent 
core is placed inside the liquid-impermeable shell and a facing comprising 
a liquid-permeable web is adhered to the so as to entrap the absorbent 
core in the shell. 
The product of this invention has a high impact capacity, i.e. the product 
accepts a relatively large quantity of liquid quickly and retains it. 
Furthermore, the product does not leak or spill over. In other words, once 
the urine enters the pad, the urine remains entrapped within the product. 
The product also has a high liquid-holding capacity. In addition, the 
product maintains its surface dry thereby keeping any moisture away from 
the skin of the wearer. Still further, the product of this invention 
permits air circulation in the region where the product is worn which 
results in a high degree of comfort.

DETAILED DESCRIPTION OF THE INVENTION 
FIG. 1 illustrates an embodiment of this invention, a urinary pad 10 in 
accordance with the teachings of the present invention. The 
liquid-impermeable backing 12 is a shell which is preformed by a thermal 
molding process known in the art. Absorbent core 13, pleated in an 
M-configuration, is fit into the shell 12. The facing 14 is a 
liquid-permeable, generally hydrophobic fibrous web which may have a 
typical weight basis of 0.5 oz/yd.sup.2. The three elements, the shell 12, 
the absorbent core 13, and the facing 14, are combined as shown in the 
drawings, the facing being sealed at its edge to the flange 25 of shell 12 
so as to provide a unitary product. 
FIG. 2 is a cross-sectional view of the pad illustrated in FIG. 1. As 
shown, an absorbent member 21 comprises two layers of a tenderized peat 
product, and, adjacent thereto, facing upwards towards the wearer of the 
product, is the receiving layer 22. The absorbent core, comprising at 
least one layer of peat moss product 21 and the receiving layer 22, is 
pleated into an M-configuration. In so doing, a channel 23 is created in 
approximately the center of the pad in a lengthwise direction which can 
serve to hold discharge until absorbed by the absorbent unit. The 
M-configured pleats are also advantageous in that they provide lateral 
compression recovery. Foam shell 12 has upper outwardly extending flanges 
25 to which are adhered a liquid permeable facing 14. There are adhesive 
means 27 on the bottom of the foam shell to facilitate adhering the pad to 
the wearer's undergarment. Adhesive 27 is protected prior to use by a 
releasable cover sheet 28. 
FIG. 3 illustrates the embodiment of a urinary pad of this invention with 
the elements thereof separated and showing their relationship. Absorbent 
core 13 comprises at least one layer of peat moss product 21 and the 
receiving layer 22. This absorbent core, after pleating into the 
aforementioned M-configuration, is placed inside foam shell 12, and facing 
14 is adhered to the flange 25 of the shell to enclose the absorbent core 
in the shell. 
FIG. 4 is a top view of a layer of peat moss product 21 of the illustrated 
embodiment showing a series of lengthwise slits 41 to allow lateral 
compression of absorbent core 13. When peat moss product 21 is combined 
with receiving layer 22 to form absorbent core 13, it is pleated into an 
M-configuration prior to being inserted into liquid impermeable shell 12. 
As a result, peat moss product 21 is substantially configured in an 
hourglass shape as shown by dotted lines 42. 
FIG. 7 illustrates a method for forming the M-configured pleat in absorbent 
core 13. Using a three-finger device (represented by a person's hand in 
FIG. 7), the center finger remains static while the two outside fingers 
move toward the center stationary finger, thus causing the M fold and a 
reduction of the pad width in its center portion. Generally, core 13 is 
squeezed, as shown, at its center and then placed into liquid impermeable 
foam shell 12 which holds it in the pleated configuration. The pleats do 
not have to be restricted to the center portion of the core and could be 
extended throughout the entire product length. 
Since the peat moss product comprising the absorbent core lacks even after 
appropriate tenderizing, sufficient cross-directional flexibility, 
lengthwise cuts or slits 41 are made in the product to render it 
sufficiently flexible to enable it to achieve the required M-fold 
configuration. 
FIG. 5 is a perspective view, and FIG. 6 is a cross-sectional view, of 
absorbent core 13 prior to pleating which shows the relationship of the 
receiving layer 22 and absorbent peat moss layers 21, 21. It will be seen 
that the three layers are co-extensive and the receiving layer 11 placed 
on top of the two peat moss layers. 
Turning now to a more detailed description of the components of the pad of 
this invention, the sheet of tenderized peat moss 21 utilized as the 
absorbent member may be made by methods well known in the art, such as 
those disclosed in the patents the disclosures of which were previously 
incorporated by reference. Generally, the raw peat moss material utilized 
is peat moss of the sphagnum variety and is preferably capable of 
absorbing at least about 15 times, preferably about 20 times, its weight 
in water. The peat moss is generally screened and then separated into a 
usable fraction and peat fines. The screened peat moss may be combined 
with other absorbent materials, preferably fibrous and cellulosic in 
nature. These art-recognized materials may include kraft, wood pulp and 
mechanical wood pulp. As used herein, the term "mechanical wood pulp" is 
meant to include ground wood pulp, thermomechanical pulp and refiner wood 
pulp. The common characteristic of these mechanical pulps is that no 
attempt has been made to separate the fibers by chemical means although 
they may later, after being reduced to fine particulate matter, be 
subjected to chemical treatment. Preferably, when mechanical wood pulp is 
used in the board of this invention, such mechanical wood pulp has a 
Canadian Standard Freeness (TAPPI TEST METHOD T-227) of from about 60-500 
and preferably from about 150-300. Another valuable material used in 
combination with peat moss is kraft wood pulp. This material is generally 
a chemically treated, long fibered pulp such as sulfite and sulfate wood 
pulps. A suitable mixture of ingredients for the absorbent boards of the 
invention may comprise from about 5 to about 20 percent by weight of kraft 
wood pulp, with the remainder being essentially peat moss. It is 
understood that these compositions are preferred peat moss embodiments and 
that those familiar with the art may find a wide range of peat moss 
compositions as well as other absorbent materials, i.e., superabsorbents, 
for use with the products of this invention. 
The above peat mixtures can be additionally combined with fibrous means 
comprising polymer fibers, preferably polyester fibers, and most 
preferably staple-length polyester fibers. The preferred polyester fibers 
are disposed to maintain the integrity of the product during processing 
and use, without subtracting from the intended mechanical flexibility. 
Preferably the polyester material or other suitable fibrous material is 
slurried with water in a pulper prior to being mixed with the preferred 
peat moss compositions. The preferred absorbent elements of this invention 
can comprise about 2.5% to about 20.0% polyester by weight, preferably 
about 4.0 to 8.0% polyester by weight. The term "peat moss", then, as used 
herein to describe the first absorbent member of the absorbent core, is 
intended to include peat moss products comprising, in addition to 
particles of peat moss, cellulosic fibers and polymer fibers as described 
above. 
The mixture of screened peat moss and selected fibers are processed into an 
absorbent element by methods known in the art. Generally, the screened 
peat moss and selected fibers are slurried together to form an aqueous 
slurry which is preferably flowed onto a Fourdrinier wire and dewatered to 
form the starting board. In the most preferred embodiment, a laminate is 
then made from the peat board and layers of kraft wood pulp. The resulting 
composite board is then conditioned to a desired moisture content and 
calendared. This calendaring step serves to densify the composite board 
and thereby provide it with its necessary high liquid retention 
capabilities. 
The absorbent elements prepared as described above tend not to be flexible 
enough for use in an absorbent device without undergoing "tenderizing", 
i.e., processing by any number of known methods to increase the 
flexibility of the board. See, for example, the disclosure of U.S. Ser. 
No. 242,274, filed Sept. 12, 1988, which discloses a method of tenderizing 
the absorbent element by a special cutting process which severs the peat 
moss portions of the element but which leaves those portions linked with 
fibrous means to produce a hinge-like effect in the resulting element. The 
teachings of said U.S. Ser. No. 242,274 are incorporated herein by 
reference. Other "tenderizing" methods which might be employed to enhance 
the flexibility of the absorbent board are microcorrugation and 
perfembossing as disclosed in U.S. Pat. No. 4,605,402 to Iskra. 
The absorbent peat moss board is generally cut into a rectangular or 
"racetrack" shape and, to enhance its cross-directional flexibility, is 
provided with a plurality of lengthwise slits 41 adjacent each of its 
lengthwise edges. These slits are preferably several in number along each 
edge and increase in length from the center of the sheet to the respective 
side edges. By increasing the cross-directional flexibility of the peat 
moss board, it is not only easier to shape it in the desired hourglass 
configuration and fit it into the liquid-impermeable shell, but more of 
the highly absorbent peat moss material is concentrated in the crotch 
region of pad 10. 
As illustrated in the Figures, one or more layers of peat moss material may 
be used as the absorbent element. Obviously, the greater the absorptive 
capacity which is desired for the final product, the more absorptive 
capacity must be provided in the absorbent core. As the peat moss boards 
decrease in flexibility with thickness, it may be desired, as illustrated, 
to utilize two (or more) layers of peat moss board in lieu of one thicker 
layer. 
The material from which the receiving layer is made generally contains wood 
pulp fibers. Wood pulp is highly wettable, but collapses when wet. 
Non-cellulosic synthetic fibers such as but not limited to polyolefin 
fibers (polyethylene, polypropylene, and bicomponent fibers) are just the 
opposite. They do not collapse as much due to their hydrophobicity. Thus, 
it has been found that by blending these two materials together, a medium 
with an optimum absorbency can be obtained. Blending about 5 to 50 weight 
%, preferably about 20-30 weight %, of non-cellulosic synthetic fibers 
with the wood pulp fibers leads to a material with markedly improved wet 
collapse properties compared to straight wood pulp, but which 
substantially retains the wettability properties of the wood pulp. In the 
preferred embodiment of this invention, the absorbent medium comprises 
approximately 80% by weight wood pulp and approximately 20% bicomponent 
fiber (polyester core/polyethylene sheath fiber of 3d and 11/2 staple) and 
weighs 11 oz/yd.sup.2. Receiving layer 22 should be capable of absorbing 
at least about 10 cc of aqueous based liquid (i.e. water or urine) at a 
rate of 10 cc/second. Preferably, receiving layer 22 is capable of 
absorbing at least about 50 cc of aqueous based liquid (i.e. water or 
urine), and more preferably at least 80 cc of said liquid, at a rate of 
about 10 cc/second. 
The absorbent web of wood pulp/noncellulosic synthetic fiber can be 
prepared by methods known in the art utilizing a transverse webber as 
disclosed in U.S. Pat. application Ser. No. 99,875, filed Sept. 22, 1987, 
the disclosure of which is incorporated herein by reference. A roll of 
pulp board and fiber web may be fed individually to the webber, ground so 
as to individualize the fibers and then fed into an air stream. The 
combined pulp/synthetic fiber is collected and thermally bonded together 
to produce a stable web. 
Liquid-impermeable shell 12 is substantially flexible and is generally a 
polyethylene-containing foam shell which is preformed by a thermal molding 
process known in the art. The shell generally has a boat-like shape and 
ranges in thickness from about 1/64 to 1/4 inch, preferably about 1/16 
inch, in thickness. The shell generally has a length which ranges from 
about 4 inches to about 12 inches, a width measured from one rim to 
another across the top space from about 2 inches to about 7 inches, and a 
depth, measured from a line extending across the width at the upper shell 
rim in the central portion to the bottom of the shell interior, from about 
0.5 to about 2.5 inches. The shell is resilient, when deformed, should 
substantially return to its original shape. 
On the underside of shell 12 there may be placed adhesive attachment means 
for temporarily, but securely, adhering the shell to the crotch portion of 
the wearer's nether garment. The attachment means may comprise adhesive 
lines covered with release strips which, when peeled from the adhesive 
strips, leave the adhesive ready for use. Preferably, the attachment means 
comprise a tape 26 coated on both faces with pressure-sensitive adhesive 
27, the first face of the tape being permanently adhered to shell 12 and 
the second face being adapted to be temporarily attached to the wearer's 
undergarment. 
The ethylene-containing polymer foam shell is prepared by known thermal 
molding processing. One preferred formulation for forming the 
ethylene-containing polymer foam material is identified as Volara Type A, 
which is a crosslinked polyethylene foam. The product is manufactured and 
sold by Voltek, Ind., Lawrence, Mass. The expression "ethylene-containing 
polymer foam" used herein includes polyethylene homopolymer and 
ethylene-containing copolymers, preferably containing a major portion, by 
weight, of ethylene. It is preferred that the polymer present be 
crosslinked. Preferred comonomers, for preparing the polymers, include 
vinyl acetate, acrylic and methacrylic acids and esters, such as ethyl 
acrylate. Blends of such polymers can also be used. Preferably, the 
formulation is prepared in sheet form at approximately 1/8 inch thickness. 
The sheet is subjected to thermal molding at a temperature of about 
260.degree. F. to form the foam shell. 
The liquid-permeable facing 14 provided on the absorbent pad 10 of the 
present invention may be an apertured film, a nonwoven fabric or a similar 
material having a high degree of moisture permeability. For example, the 
nonwoven fabric may be polyester, polyethylene, polypropylene, 
bicomponent, nylon, rayon, or the like fibers. Preferably, the nonwoven 
fabric used for facing sheet 14 has a basis weight in the range of 0.3 to 
5.0 oz. per square yard and has a density less than 0.2 gms/cc. 
The most suitable nonwoven fabrics have high loft, softness and drape 
characteristics. Though the cover is moisture permeable, it is preferably 
of the type which after permeation of the moisture, prevents strike-back 
of the body fluid when the absorbent core is approaching saturation. The 
facing is readily sealable to the outer rim of the shell so as to enclose 
the absorbent core in the shell. In the preferred embodiment, the facing 
is a web of through air bonded bicomponent (polyester/polyethylene) fiber. 
Excellent results have been obtained using such a fabric of 0.7 
oz/yd.sup.2 formed from 3 denier, 11/2 bicomponent staple fiber. 
A function of peat moss product 21 is to ultimately absorb from receiving 
layer 22 the liquid which is discharged into pad 10 by the wearer. Thus, 
peat moss layer 21 must have a liquid absorption capacity sufficiently 
high to absorb the relatively large amounts of urine which can be expected 
to be discharged, either by a single large void or by two or more smaller 
voids, by an incontinent adult over the period of time the urinary device 
would be worn. Peat moss layer 21 must also function to retain and 
immobilize said discharged liquid under the pressure encountered as a 
result of the normal activities of the wearer of the device. When the 
first portion functions to retain and immobilize liquid, the possibility 
of discharged liquid flowing back into and through the receiving layer and 
facing sheet and rewetting the body of the wearer is greatly reduced. Any 
liquid not absorbed by the receiving layer can be held in the bottom of 
the cup until absorbed by the peat moss layer. Furthermore, due to the 
strong liquid extractability properties of peat moss layer 21, discharged 
liquid is gradually drawn away from facing 21 and receiving layer 22, thus 
keeping the liquid impact area dry. 
The product of the present invention is worn by the wearer in the crotch 
region, and for simplicity is secured to the underclothing of the wearer. 
Securement may be effected by the aforementioned adhesive lines or strips 
on the exterior of the shell, or the product may simply secure itself to 
the underclothing by means of friction. If the product is to be secured by 
friction, a material for manufacturing the shell is selected which will 
provide sufficient friction or a material is coated on the exterior of the 
shell to provide such friction. 
From the foregoing, it will be observed that numerous variations and 
modifications may be effected without departing from the true spirit and 
scope of the novel concept of this invention. 
The side of receiving layer 22 extend over the side edges of the central 
portion of absorbent, highly liquid-retentive peat moss layer 21 in 
assembled pad 10. Referring to FIG. 2, where absorbent unit 13 is shown in 
its M-folded configuration, it will be seen that the side of receiving 
layer 22 are disposed between the side walls of shell 12 and the thickened 
side portions 21a, 21a of peat moss layer 21. It will be understood that 
said thickened side portions 21a, 21a and the aforementioned M-fold 
configuration result from the application to absorbent unit 13 of the 
lateral compressive forces indicated by the directional arrows A,B in FIG. 
7. It will be further appreciated that said compressive forces 
simultaneously act to form liquid receiving channel 23 and provide the 
configuration of receiving layer 22 shown in FIG. 2. 
The so-positioned receiving layer 22 provides a path for liquid to flow 
between the side walls of shell 12 and the thickened peat moss side 
portions 21a, 21a.