Note: Descriptions are shown in the official language in which they were submitted.
CA 02207227 1997-06-09
PLANT SEED GERMINATION MAT
FIELD OF THE INVENTION
The present invention relates to plant seed germination mats.
s
BACKGROUND OF THE INVENTION
For many centuries, h~lm~n~ have attempted to cultivate plants and control and regulate
plant growth. Over the years there have been many objectives for such cultivation and control.
In present times, it might be desired to cultivate a lawn, a bed of flowers, a garden, or
10 commercial cash crops.
No matter what the final objective, however, as a general rule plant cultivation and
control involves getting specific plants to grow in specific locations and preventing others from
growing in other locations. It is not an easy task. Plant cultivation, and particularly plant seed
15 germination, requires that a number of variables including soil nutrient conditions, soil moisture
content, and light and temperature levels all be within a suitable range. Such conditions are
rarely optimal in nature, hence, in order to effect plant growth it is generally required that one
must first prepare the soil through a variety of techniques, plant the seeds in the desired
locations, fertilize the soil, and water as necessary depending on environmental conditions.
Each of these steps in and of itself is not simple. The soil must first be tilled and if
necessary topsoil added. Depending on the size of the plot of land, machines might be available
to aid in such work, otherwise such work might be time con~lming and physically difficult.
Hilly areas in particular may require an extreme amount of work for which machine assistance
25 may not be available.
Once the soil has been prepared, the seeds must be planted in the desired location.
Depending on the objective this task may require extreme and precise efforts. The seeds must
be placed such that the mature plants have the desired spacing, and generally do not compete
30 with one another. Such spacing will differ depending on the objective in mind and the plants
involved. For instance, grass seeds must be placed closer together (and randomly) as opposed
to garden vegetables or commercial crops, which are generally planted in spaced apart rows.
Extreme examples include flowerbeds wherein the plants, when mature, will form a coloured
pattern or design. Careful placement of the individual seeds, as well as the exclusion of all
35 other plants, is required in such an application.
CA 02207227 1997-06-09
Once the seeds have been planted, fertilizer may optionally be laid down over the soil
where nutrient conditions are poor or where it is desired to accelerate plant growth. There are
many dirrerenl types of conventional fertilizers available both in liquid and solid form
5 (generally pellets). Either form must be dispersed over the ground area in which the seeds are
located. Basically, the fertilizer so dispersed will land across the ground area in a relatively
random formation. Some areas may thus be over fertilized, others under fertilized, and some
not fertilized at all. This process is inefficient and results in wasted fertilizer.
The ground area in which the plant seeds are located must also be kept wet, as the plant
seeds will only germinate in relatively constant moisture conditions. Depending on the plants
being grown the ground may be watered at either regular intervals or when it appears dry.
Neither are particularly accurate methods for measuring soil moisture content. As with the
fertilizer, water is dispersed over the ground relatively randomly, and thus, some areas may be
15 overwatered, others underwatered, and still others not watered at all. In addition, water
provided to the plants does not simply say in the topsoil where the seeds are located, but rather
will seep into the layers below becoming unavailable to the seeds. The amount of watering
done must take such waste into account. The entire watering process thus is ineff1cient and
wasteful.
Even once all of the above steps have been accomplished, the work has not ended.Birds and other small ~nimAI.~ Iike to eat the seeds and continual efforts must be made to keep
such ~nim~l~ away and to replace the seeds that have been eaten by them. Constant efforts
must also be expended to m~int~in the area free of unwanted plant growth resl-lting from
25 natural seed placement in the area or from seeds already present in the spoil before the desired
seeds were planted.
One way in which some of these difficulties have been previously attempted to have
been overcome is through the production and use of sod. Sod is a small piece of a layer of turf
30 that has been cut from the earth. It contains both mature plants (including roots) and a small
layer of soil underlying them. Sod is generally used as quick means of producing a lawn (of
grass). In order to do this, a number of pieces of sod are placed side-by-side over an area of
the ground in which it is desired that the grass grow. It is then watered, and optionally
fertilized, and it is hoped that the desired end will be achieved. There are, however, many
35 problems with sod: As it must be grown as a crop, it takes a relatively long-time and large
CA 02207227 1997-06-09
ground area to produce on a commercial scale. As it is a live plant, its soil component must be
kept constantly moist in order to prevent it from dying before use. It is thus expensive and
impractical to store for an extended period of time. Moreover, in use it is heavy, dirty, time-
con~l~ming, and difficult to handle and requires lots of equipment. It often dies despite the best
efforts of the user.
In sum, at present the plant cultivation, control, and regulation process is a difficult one.
Efforts made to alleviate these difficulties have not met with complete success. It would be
desirable to devise a means, method and/or appa ~L~Is for red~lring the amount of work and
10 materials required to cultivate, control and regulate plant growth.
OBJECT AND STATEMENT OF THE INVENTION
It is therefore an object of the present invention to provide a means and a method for
15 cultivating, controlling, and re~ ting plant growth requiring less work and materials than is
conventionally required.
In a first aspect, as embodied and broadly described herein, the present invention
provides a plant seed germination mat comprising a structurally integral layer of sph~gmlm
20 moss particles, said layer capable of being penetrated by a cotyledon. Preferably, a plurality of
plant seeds affixed are to the underside of said layer (i.e. the soil-facing side of the mat when
the mat is in use).
In another aspect, as embodied and broadly described herein, the present invention
25 provides a plant seed germination mat comprising:
(a) a substrate, said substrate including a structurally integral layer comprising
sph~gn-~m moss particles;
(b) a plurality of plant seeds ~it~1~ted on said substrate; and
(c) a cover layer affixed to said substrate at least partially covering said substrate and
said plant seeds, said cover layer capable of being penetrated by a cotyledon.
The structurally integral sph~gnllm moss layers of the present invention have been
m~mlf~ctured for some time for use in articles used to absorb bodily exudates (e.g. feminine
sanitary napkins, tampons, medical bandages, Band-AidsTM). Sph~gnllm layers are employed
35 in such articles owning to their excellent liquid absorbent properties; they are capable of
CA 02207227 1997-06-09
absorbing and ret~ining a significant amount of liquid over periods of time. They are, however,
stored dry. Such layers and the m~nllf~cture thereof are described in the following patent
documents, which are all incorporated herein by reference:
......................................................................................................... ......
_ S-A-' ,1. 0,'15 Ja ancette et a~. Octo ~er 9, 1979
US-A-4,215,692 Levesque August 5, 1980
US-A-4,226,237 Levesque October7, 1980
US-A-4,305,393 Nguyen December 15, 1981
US-A-4,473,440 Ovans September25, 1984
US-A- 4,507,122 Levesque March26, 1986
US-A-4,618,496 Brasseur October 21, 1986
US-A-4,676,871 Cadieuxetal. June30, 1987
US-A-4,992,324 Dubé February 12, 1991
US-A-5,053,029 Yang October 1, 1991
WO 97/13484 Roy et al. April 17, 1997
These properties of the sph~gmlm layers allow the present invention to be a significant
improvement over conventional plant cultivation techniques. The present germination mats
may be m~nllf~ctured on large scale as relatively large yet lightweight sheets, they may be
10 rolled into a roll and stored dry for çxten(led periods of time if necessary, enabling long-term
storage while decreasing both storage and transportation costs (as co,l,paled with sod.)
More significant benefits accrue to the end user of the present mats. In effect, the
present invention allows the user to dispense with the steps of tilling the soil, positioning and
15 planting the seeds, and fertilizing. All that is necessary is that the user unroll the present
germination mats, sever them to the desired shape and size (as necessary), place them on the
soil and water. Depending on the mat, the seeds may have been precisely placed within the
mat at desired locations, or may have been randomly placed, thus simplifying the seed
placement process. Moreover, the amount of work necessary to m~int~in the seeds is also
20 decreased. The structurally integral sph~m-m layers of the present invention will absorb and
retain a large amount of water, as opposed to simply allowing it to seep through to the ground
underneath. The plant seeds of the present invention therefore effectively have water constantly
available to them, presenting a more ideal situation for seed germination, and likely increasing
CA 02207227 1997-06-09
S
the germination rate. The amount of weeding required is reduced as the present germination
mats contain only the plant seeds which were intentionally placed in them during their
manufacture. Other plant seeds present in the soil below are less likely to germinate, as the
present mats will greatly decrease the amount of sunlight and water available to them.
5 Furthermore, as the present plant seeds are shielded by the cover layer of the present
germination mat, they are much less likely to be disturbed by anim~l~ in the area. In addition,
as the sph~gn~-m layers decay they will constitute a natural fertilizer and make nutrients
available to the sprouting see(lling.~. The present germination mats are thus a significant
development in plant cultivation.
Preferably, the cover layer includes a structurally integral layer comprising cellulose
fibres, particularly wood pulp fibres. Such a cover layer would serve to secure the seeds within
the mat, to protect the seeds during the primary stages of their growth and to impede their being
eaten by birds and other animals.
Preferably, the cover layer includes a structurally integral layer comprising sph~gmlm
moss particles. Such a layer would increase the aforementioned benefits conferred by the
sph~p~n-lm moss particles, i.e. more water may be retained by the mat, less water and sllnlight
pass through the mat, and more natural fertilizer is available as the sph~gnl1m decays. Such a
20 layer would also constitute a greater prevention from unwanted animal interference with the
seeds below. The reason for this is that a sph~n-lm moss cover layer is generally thicker and
denser than a simple cellulose fibre cover layer. Where such is the case, preferably, the cover
layer includes a plurality of perforations. Depending on the type of plant seeds, the growing
plant cotyledons may not be strong enough to penetrate the sph~gnllm cover layer. They will
25 thus grow sideways, in between the cover layer and the substrate and will exit the germination
mat through one of the pel~ol~lions. For this reason, the perforations need not be aligned with
plant seeds, and the seeds may be randomly situated in the mat. Moreover, the placement of the
holes permits the selection of the position of the mature plants which develop from the seeds.
In some situations, e.g. a lawn, the perforations are preferably evenly spaced apart, generally in
30 rows and in columns. In other situations, it may be desired to produce a pattern out of the
mature plants, and the holes may be placed so as to cause the mature plants to be of such a
pattern.
Preferably, the mat is substantially free of synthetic material, and particularly polyester.
35 Polyester is present in structurally integral layers of sph~gnllm moss conventionally used in
CA 02207227 1997-06-09
absorbent articles, for various reasons. In order to render the entire present germination mat
biodegradable and thus more environmentally friendly, the mat should be free of polyester, and
all other non-biodegradable synthetic materials.
Preferably, the mat further includes a fertilizer. Such may be necessary where soil
conditions are particularly poor in the area. Any conventional fertilizer which will not harm the
seeds may be used. Such fertilizer may be impregn~ted into either the substrate or the cover
layer (or both) during the course of m~n~lf~chlre thereof, or alternatively, may be dispersed
(either in solid or liquid form) along the substrate in a similar manner as with the plant seeds.
Preferably, the mat includes an indicator of the variety of the seeds, and all conventional
indicators are within the scope of the present invention. Thus, for example, the name of the
variety might appear on either the cover layer or the substrate. It is more prerelled that at least
a zone of the cover layer be coloured to indicate a variety of the seeds.
Preferably, the mat includes an indicator of the in use position of the mat, and all
conventional indicators are within the scope of the present invention. In this manner, the mat
may be correctly positioned when in use, i.e. with the substrate in contact with the ground and
the cover layer facing the environment. It is more p.er~.led that such indicator be a colour of at
least a portion of the cover layer or of the substrate. The pe-ro~alions of the cover layer may
also act as an indicator in this respect.
Preferably, the cover layer includes an indicator of the moisture content of the cover
layer, and all conventional indicators are within the scope of the present invention. In this
manner, it will be easier to discern when the mat (and thus the seeds) should be watered. Such
an indicator may be a substance added to at least a portion of the cover layer which turns
different colours when wet and when dry. Sph~gnllm itself is such a material (it being darker
when wet and lighter when dry) and thus when the cover layer is a structurally integral
sph~gn..m layer, it may not be necessary to add an additional material to the mat to serve as
30 such an indicator.
Preferably, at least a portion of the cover layer approxi---ates a colour of at least a flower
of a plant grown from the seeds. In this manner a carpet or field effect may be created, such
that, as an example, where the mature flowers are yellow, the cover layer of the mat is dyed
35 yellow so that the entire area appears yellow instead of having yellow flowers with brown
CA 02207227 1997-06-09
patches in between. It should be understood whenever in the context of the present invention a
dye is added to the mat or any layer thereof, the dye should be non-toxic to both the seeds and
the mature plants.
Preferably, the cover layer includes a zone capable of ~suming at least a first colour at
a first pH and at least a second colour at a second pH, for indicating the pH of the mat. In this
respect, a material typically known as a pH indicator may be incorporated into the cover layer
to allow for a simple means of determining the acidity/~lk~linity of the mat. (So that it may be
determined whether same needs to be adjusted to enhance seed germination and plant growth.)
Any conventional pH indicator may be so incorporated into the mat, provided it is not harmful
to the seeds or the growing plants.
In yet another aspect, as embodied and broadly described herein, the present invention
comprises a method of growing plants comprising the steps of placing a plant seed germination
mat as previously recited on soil, and then watering the mat.
In still another aspect, as embodied and broadly described herein, the present invention
comprises a plant seed germination mat comprising:
(a) a substrate, said substrate including a structurally integral layer comprising
sph~gnl-m moss particles, said substrate capable of being penetrated by a cotyledon;
and
(b) a plurality of plant seeds incorporated into said substrate.
In this embodiment the plant seeds are physically incorporated into the substrate, thus
the substrate both supports and covers the seeds. In all other aspects, this embodiment is
similar to that described above, including the colouring of the substrate for various purposes,
and the addition of fertilizer thereto.
In still another aspect, as embodied and broadly described herein, the present invention
still further comprises a method of making a plant seed germination mat comprising the steps
of:
(a) providing a substrate including sph~gnllm moss particles;
(b) supporting a plurality of plant seeds by the substrate;
(c) providing a cover layer on the plant seeds, the cover layer capable of being penetrated by a cotyledon; and
CA 02207227 1997-06-09
(d) ~fflxing the cover layer to the substrate.
The cover layer may be affixed to the substrate by any conventional means which are
non-toxic to the plant seeds and mature plants. Preferably such means are biodegradable, glues
are p~erelled. No particular sealing pattern is essenti~l to the present invention, however it
should be noted that the cover layer and substrate should not be completely affixed to another to
allow sideways plant cotyledon growth to a p~lrol~lion in the cover layer.
In still yet another aspect, as embodied and broadly described herein, the present
10 invention provides a method of producing a flower bed having a pattern comprising the steps of
(a) providing a first seed germination mat having:
(i) a substrate, the substrate including a structurally integral layer of sph~gmlm
moss;
(ii) a plurality of a first variety of flowering plant seeds .sitll~ted on the substrate;
(iii) a cover layer affixed to said substrate covering the substrate and the plant
seeds, the cover layer capable of being penetrated by a cotyledon;
(b) providing a second seed germination mat having:
(i) a substrate, the substrate including a structurally integral layer of sph~gm-m
moss;
(ii) a plurality of a second variety of flowering plant seeds sit~l~ted on the
substrate;
(iii) a cover layer affixed to said substrate covering the substrate and the plant
seeds, the cover layer capable of being penetrated by a cotyledon;
(c) severing the first seed germination mat in accordance with the pattern;
(d) severing the second seed germination mat in accordance with the pattern;
(e) positioning the severed first seed germination mat on the soil in accordance with the
pattern; and
(f) positioning the severed second seed germination mat on the soil in accordance with
the pattern.
This aspect of the present invention allows the formation of complicated plant patterns
(colour variations) more easily than is conventionally done. A desired pattern is selected and
pieces of a germination mat of the present invention are severed and placed on the soil in
accordance therewith. It should be noted that the number of dirrelel,l types of plants (i.e.
germination mats co~ ning different plant seeds) which may be used in this manner is not
CA 02207227 1997-06-09
limited to two. Depending on the size of the area to be cultivated, a large number of different
germination mats may be used.
Other objects and features of the invention will become apparenl by reference to the
following description and the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
A detailed description of prerelled embodiments of the present invention is provided
hereinbelow with reference to the following drawings, in which:
Figure 1 is perspective view of a plant seed germination mat;
Figure 2 is a top plan view of the mat of Figure 1, with a portion of the cover layer cut
away to reveal the substrate;
Figure 3 is a cross-sectional side view of a plant seed germination mat including a
15 germin~ted seed;
Figure 4 is a perspective view of a plant seed germination mat including germin~ted
seeds;
Figure 5 is a cross-sectional side elevational view of a plant seed germination mat
including a germin~ted seed having roots;
Figure 6 is a cross-sectional side view of a second embodiment of a plant seed
germination mat similar to Figure 5;
Figure 7 is a cross-sectional side view of a third embodiment of a plant seed
germination mat similar to Figure 5;
Figure 8 is a pe-~l,ecli~e view of a flowerbed having a design having been formed
25 through the use of plant seed germination mats;
Figure 9 is a schematic diagram of the apparatus for the m~mlf~ctllre of a structurally
integral sph~gnl.m moss layer; and
Figure 10 is a schematic diagram of the appa ~ s for the m~nl-f~ct-lre of a plant seed
germination mat of the present invention from the structurally integral sph~gn~lm moss layers
30 m~nllf~ct~lred as per Figure 7.
In the drawings, pr~relled embodiments of the invention are illustrated by way of
example. It is to be expressly understood that the description and drawings are only for
purposes of illustration and as aid to underst~n-ling and are not inten~1ed to be a definition of
35 the limits of the invention.
CA 02207227 1997-06-09
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
Referring to Figs. 1, 2, 3, and 4, in its pl~felled embodiment, the present invention
comprises a plant seed germination mat 20. The mat may be of any shape and size as is feasible
5 to m~nllf~ctllre, manipulate, and store. It is illustrated in the drawings as a relatively small
square merely for discussion purposes. The mat 20 is of a l~min~te construction and comprises
two distinct layers, a substrate 22 and a cover layer 24. In its in use position the mat the
substrate 22 will be in contact with the soil 36 and the cover layer 24 will face the environment.
Both the substrate 22 and the cover layer 24 comprise four different sublayers. With
respect to the substrate 22, in order from soil cont~ctin~ sublayer up these are a first wood pulp
sublayer 22a, a first structurally integral sph~gn~m layer 22b, a second structurally integral
layer 22c, and a second wood pulp layer 22d. The overall thickness of the substrate 22 is
approximately 0.043", its basic weight 308 g/m2. Similarly, the cover layer 24 comprises a first
15 wood pulp sublayer 24a, a first structurally integral sph~gn-lm sublayer 24b, a second
structurally integral sph~gmlm sublayer 24c, and a second wood pulp sublayer 24d. The overall
thickness ofthe cover layer 24 is approximately 0.030", its basic weight 175 g/m2.
The cover layer 24 includes a plurality of evenly-spaced apart perforations 30. The
20 pe~ro~lions 30 are in the shape of an X and are aligned along a grid 0.4" apart (as measured
along a line 32 from perforation centre to perforation centre). The length of each of the bars
30a of the perforation 30 is 0.25" while the inter-bar distance 30b at the top of the perforation
30is0.2".
Situated between the substrate 22 and the cover layer 24 are a plurality of plant seeds
26. The plant seeds 26 are flowering plant seeds 26, preferably flowering plant seeds of mixed
variety currently sold by White Swan Inc. of Beaverton, Oregon, USA under the trademark
FIELD OF FLOWERSTM. The plant seeds 26 have been randomly dispersed along the
substrate 22 with a seed density of 60 seeds/ft2. There is no particular relationship of the
placement of the plant seeds to the perforations.
The substrate 22 and the cover layer 24 are afflxed with conventional hot melt type glue
(not shown). No particularly gluing pattern is essential to the present invention, although the
complete faces of either layer are not affixed together so as to allow for sideways cotyledon
growth between the substrate and the cover layer.
CA 02207227 1997-06-09
11
The fabrication of the germination mat 20 first proceeds with the m~mlf~ctllre of the
individual layers of which it is comprised. Referring to Figure 9, the m~nllf~cturing
appa~ s, desi~n~ted comprehensively by the reference numeral 100, comprises an endless,
fluid-pervious Fourdrinier wire 102 which is mounted on rollers 104 to provide a horizontally
.xte.ntJing run 108 that is continuously advanced forward to support and convey a slurry of
sph~gmlm moss and cellulosic fibers through various processing stations.
Headboxes 110, 112, 114 and 116 arranged in a spaced apart relationship along the path of
10 travel of the wire 102 are provided to lay on the wire 102 slurry in sheeted form. The headbox
bank deposits on the wire 102 four (4) layers of slurry in a superposed relationship to form a
l~min~ted slurry web. More specifically, the headboxes 112 and 114 lay slurries co~ ining
sph~gn--m moss while the headboxes 110 and 116 deliver slurries of fibrous material such as Kraft
wood pulp or any other suitable substance.
In the p.epal~lion of the sph~gnllm moss slurry layers supplied to headboxes 112 and 114
a mother slurry is prepared by dispersing raw sph~gnl1m moss material in water. The mother
slurry is wet classified to retain only the particles having a size in the range from about 74 microns
to about 2000 microns. The screened fraction is then diluted with water to render the slurry more
20 manageable.
It is ple~llt;d to add a fibrous component, such as Kraft wood pulp prior to supplying the
slurry to headbox 114. Suitable fibrous components may include such materials as Kraft wood
pulp, cross-linked cellulose fibers, meçh~nical wood pulp, natural textile fibers, and mixtures
25 thereo~ The fibrous components are generally added to the headbox in an amount from 2 to 20%
by weight ofthe sph~gn~lm layer to be m~nllf~ctllred, preferably from 2% to 6%. As used herein,
the term mechanical wood pulp is meant to include ground wood pulp, thermo-mechanical pulp
and refiner wood pulp. Ground wood pulp is essçnti~lly trees and branches which have been
debarked, cleaned and ground into particulate matter. Refiner wood pulp differs from ground wood
30 pulp only in that the grinding step utilizes a refiner, i.e. a disc-like device well-known in the art and
having metallic ribs at the peripheral sections thereof which last contact the wood particles and
help separate the wood fibers without excessively d~m~ging them. Thermo-mechanical wood pulp
is similar to refiner pulp with the exception that the wood particles are heated in the refiner, usually
with steam, to aid in separating the wood fibers. The common characteristic of these mechanical
35 pulps is that no attempt has been made to sepalale the fibers by chemical means although they may
CA 02207227 1997-06-09
12
later, after being reduced to fine particulate matter, be subjected to a desired chemical treatment,
such as bleaching. Preferably, when mechanical wood pulp is used in a sph~n~lm moss slurry,
such mechanical pulp has a Canadian Standard Freeness (TAPPI test method T-227), in a range of
from about 60 to 750 and pr~r~l ~bly from about 400 to 600.
The Kraft wood pulp, also usable in combination with sph~gn-lm moss, is essenti~lly
chemically treated, long fibred wood pulp such as sulphite and sulphate wood pulps.
As illustrated in Figure 3, a slurry of Kraft wood pulp layer having a consistency of about
0.2% by weight of solids is first laid down on the wire 102 from the headbox 110 in order to form
the bottom Kraft reinrol~iing layer 22a. The slurry flow rate is selected to deliver on the wire 102,
15 grams of solids per square meter. The Kraft slurry passes under the headbox 110 which delivers
on top of the Kraft layer a slurry of sph~gnl-m moss particles. The consistency of the sph~nllm
moss slurry fraction is set at 0.5% by weight of solids. The flow rate of the slurry fraction is
selected to deliver 142.5 grams of solids per square meter on the wire 102.
The headbox 114 delivers a second slurry fraction of sph~gnllm moss particles
intermixed with cellulosic cross-linked fibers. This slurry fraction has a consistency of 0.5% by
weight of solids, a flow rate to deliver 145.5 grams of solids per square meter on the wire 102.
20 The slurry contains sph~gnllm moss in the range from about 25% to 95% by weight of solids in
the slurry, and cross-linked cellulosic fibers in the range from about 5% to about 75% by
weight.
A final Kraft wood pulp slurry layer is laid from the headbox 116 on the sph~m-m25 moss slurry in order to form the reinforcing top layer 22d. This final layer was identical in
terms of consistency and composition to the bottom Kraft wood pulp layer 22a previously
deposited except that the flow rate was such as to deposit on a square meter of the wire 102 five
grams of solids.
The resulting l~min~ted slurry layer Kraft/Sph~nllm/Sph~gnum/Kraft is then passed
over a vacuum slot 118 to extract water under the influence of a pressure differential
established across the slurry layer. It is necessary to regulate the residence time of the slurry
layer over the vacuum slot 118 and the vacuum intensity in order to control the density of the
final product. Generally, decreased vacuum and increased speed will result in a less dense
product. Conversely, increased vacuum and decreased speed will produce a denser product.
CA 02207227 1997-06-09
13
The web leaving the vacuum slot 118 passed through a dryer 120 whose purpose is to
elevate the temperature of the web to evaporate residual water. The dryer 120 is of a
well-known construction and does not require a detailed description herein.
It may be envisaged to add between the dryer 120 and the vacuum slot 118 a presssection (not shown in the drawings) to mechanically express water from the web, as it is
well-known to those skilled in the art, in order to reduce the water contents in the web as much
as possible before it is processed in the dryer 120.
Downstream of the dryer 120 a calendering station 122 is provided which mechanically
compresses the dried product in order to densify the sph~gn~1m moss material for enhancing its
drying power. If desired, the calendering station 122 may be followed by a perf-embossing
station (not shown in the drawings) provided to tenderize the web by mechanical working. This
15 treatment softens the sph~gnl-m moss structure for enhancing its comfort potential. The
calendering operation is described in detail in the international application PCT/CA92/00308
filed on July 20, 1992 in the name of Johnson & Johnson Inc. The contents of this application is
incorporated herein by reference.
An alternative to the perf-embossing technique is the micro-corrugating operation which
is similar to the perf-embossing except that no pelîolalions are performed. The liquid-absorbent
structure is solely subjected to an embossing operation to create closely spaced hinge lines. The
micro-corrugating operation is described in US patents granted to Personal Products Company
4,596,567 and 4,559,050 issued on June 24, 1986 and December 17, 1988 respectively. The
contents of these patents is incorporated herein by reference.
The fabrication of the cover layer 24 proceeds in a similar manner except that the
material deposition rates have been suitably altered to provide a cover layer 24 with the correct
thickness and basic weight. Additionally, at the end of the process, the cover layer 24, may
optionally be perforated through conventional means, e.g. punching or die cutting. A grid-like
perforation pattern as previously described is plefelled.
Referring to Figure 10, the germination mats 20 are m~mlf~ctllred by providing the dry
substrate 22 on a endless belt 156 (Possibly, as shown in Figure 10, directly after their
m~n~lf~ctllre.) As the belt 156 moves ~olward, the dry substrate 22 is first passed through a
CA 02207227 1997-06-09
14
gluing stationing 158 where glue is applied thereto in the desired gluing pattern. Next, seeds
(stored in a hopper 160) are ~itu~ted on the substrate 22, also in the desired pattern. Such
pattern may be random or may be precise. In the preferred embodiment the seeds are random at
a density of approxhllately 60 seeds/ft2. The cover layer 24 is then aligned with the substrate 22
and placed on top thereof 130. Optionally, the final product is then manipulated for storage and
transport, which may include rolling or slicing into smaller pieces.
Referring to Figure 6, in an alternative embodiment of the present invention, the seeds
626 of the germination mat 620 have been incorporated into the substrate 622 in between the
10 first sph~gnum layer and the second sph~gnllm layer. Such mat 620 may be m~m~f~ct~red as
previously described except that the seeds 626 would be deposited on the first sph~gmlm layer
after headbox 112 (but before headbox 114) in Figure 9. If necessary, the seeds may be
microencapsulated to prevent their becoming wet to prevent their premature germination during
the m~mlf~cturing and storage of the mat 620. In addition, it may be necessary to alter the
15 temperature of the dryer 120 to prevent the seeds from being damaged by the heat thereof.
Referring to Figure 7, in another alternative embodiment of the present invention, the
seeds 726 of the germination mat 720 have simply been affixed to the underside of a
structurally integral sph~gm~m layer 722. (Illustrated as being of a reduced thickness as
20 compared with the substrates 22 and 622). Such layer 722 forms a cover layer over the seeds
726 and no substrate is present. Such mats may be m~nuf~ctured as previously described (in
Figure 9) with the seeds being affixed to one side thereof with conventional non-toxic glue
during the m~nuf~chlring process (such side will become the soil-facing side [underside] of the
mat when the mat is in use.)
The use of the germination mat 20 (or 620 or 720) is relatively simple. First, a plot of
land on which the plants will be grown is selected. No particular amount or shape of land is
necessary for the use of the present invention. Any plot of land will suffice as long as the soil
thereof is capable of sust~ining plant life. It is plerelled that the topsoil thereof by lightly tilled
30 before the germination mat 20 be applied thereto, but such is not essçnti~l
Next a germination mat having the desired characteristics must be selected. Suchcharacteristics are generally the following: type and arrangement of plant seeds present in the
mat, presence and type of a fertilizer present in the mat, colour(s) of mat, watering requirements
35 of mat, etc. Each of these variables will be selected as a function of both the environment of
CA 02207227 1997-06-09
the plants to be grown and the wishes of the cultivator. Primarily, the germination mat 20 must
contain the plants seeds desired to be grown and have same be present in the appropliate layout.
For example, if it is desired to grow grass, a germination mat having grass seeds randomly
dispersed throughout should be selected. Alternatively, if it is desired to grow marigolds in a
5 rows, then a germination mat having marigold seeds in that configuration should be selected.
Optionally, the germination mat 20 may contain additional ingredients such as a fertilizer.
Depending on the amount of land to be covered and the size of the germination mat, more than
one mat may be necessary.
The mats are generally stored dry in rolls. If necessary, they must be unrolled and are
then severed into the desired shape and size to cover the desired amount of land. Any
conventional means such as garden shears or even scissors may be used to severe the mats 20.
They are placed on the soil with the substrate 22 in contact with the soil 36 and the cover layer
24 facing the environment. They are then watered until they are soaked full of water (absorbed
15 by the integral sph~gnum layers). The cover layer 24 will act as an indicator of the moisture
content of the germination 20, as the sph~gnl1m thereof will turn dark when full of water.
The mats and the plants which grow therefrom are then cared for in the same manner as
would be oldinaly seedling~. Generally this care will include periodic watering (the necessity
20 of which may be judged by the colour of the sph~gnl-m cover layer), weeding, and in some
cases, the application of fertilizer.
Referring to Figures 3 and 5, after a short period of time the plant seeds 26 will begin to
germinate and a plant cotyledon 28 will grow forth and exit the mat 20 either by simply
25 growing through the cover layer 24 or by growing out of one of the perforations 30. As time
progresses, roots 34 will spring forth from the seeds 26 and will grow through (penetrate) the
substrate 22 to the soil below.
Although the mats 20 are not adhered to the soil 36 below, first owning to their weight,
30 and later as a result of plant roots 34, they should not shift relative to the ground. In rare
circum.et~nces, it may however be necessary to place a shifted germination mat 20 back into
posltlon.
Finally, referring to Figure 8 there is illustrated an additional method of using the
35 present plant seeds germination mats 20. In this instance it is desired to have the mature plants
CA 02207227 1997-06-09
16
form a pattern, in the present example the word ZONE. Thus germination mats were severed
such they formed the letters Z 38, O 40, N 42, E 44. An unlimited number of patterns and
shapes can be formed in this manner. Moreover, should it be so desired, germination mats
could be severed to fit in the area 46 surrounding the letters ZONE, yielding an entire patterned
S flower bed.
The above description of plerelled embodiments should not be interpreted in a limiting
manner since other variations, modifications and refinements are possible within the spirit and
scope of the present invention. The scope of the invention is defined in the appended claims
10 and their equivalents.
