A disposable cat litter box includes a container and a fresh litter
enclosed within the container. The container is convertible between
a closed condition in which it forms a closed receptacle and an
open condition in which it forms an open receptacle. The fresh litter
comprises a plurality of transversely folded paper strips which
exhibit a noticeable color change when wetted with cat urine having
a predetermined characteristic of feline disease.
What is claimed is:
1. A disposable kitty litter box comprising a container which forms
a closed receptacle and fresh kitty litter which is enclosed within
the closed receptacle;
the container being convertible between a closed condition, in
which it forms the closed receptacle, and open condition in which
it forms an open receptacle;
the fresh kitty litter comprising a plurality of transversely folded
paper strips which exhibit a noticeable color change when wetted
with cat urine having a predetermined characteristic of a feline
2. A disposable kitty litter box is set forth in claim 1 wherein
the paper strips have further been treated with sizing in an amount
sufficient to permit the strips to wet from the bottom upwards when
the cat urinates on top of the strips.
3. A disposable kitty litter box is set forth in claim 1 wherein
the folded paper strips are made from bleached kraft paper whereby
any unusual color in the cat's urine will be observable.
4. A kitty litter box is set forth in claim 1 wherein said strips
intertwine and interlock to combine and form a mass.
5. A disposable kitty litter box is set forth in claim 4 wherein
the mass has a density between about 0.01 and 0.100 ounces per cubic
6. A disposable kitty litter box as set forth in claim 1 wherein
all of the strips have been treated with an indicator causing the
strips to exhibit a noticeable color change when wetted with cat
urine having the predetermined characteristic of the feline disease.
7. A disposable kitty litter box as set forth in claim 1 wherein
the paper strips are made from kraft paper.
8. A disposable kitty litter box as set forth in claim 1 wherein
most of the paper strips have been treated with an indicator causing
the strips to exhibit a noticeable color change when wetted with
cat urine having the predetermined characteristic of the feline
Cat litter descriptionFIELD OF THE INVENTION
This invention relates generally to a cat litter, and more particularly
to a resilient paper cat litter and method for detecting feline
diseases which are indicated by a predetermined characteristic of
the cat's urine, such as a particular pH range and/or blood in the
cat's urine. Feline diseases which may be thus detected include
feline urinary tract diseases, such as feline urological syndrome
("FUS") or feline lower urinary tract disease ("FLUTD"),
and/or cystisis (bladder infection).
BACKGROUND OF THE INVENTION
FUS is a term used to describe a group of clinical signs and symptoms
associated with diseases of the urinary tract of male and female
cats. Manifestations of FUS include frequent trips to the litter
box, straining to urinate with little result, blood in the urine
(particularly occult or microscopic blood in the early stages of
the disease), urination in inappropriate places, and even pain during
urination. The cat may also pace, lick itself, and cry.
The manifestations of FUS are often the result of the formation
of mineral crystals, usually struvite, in the cat's urine. Struvite
crystals are generally comprised of a magnesium ammonium phosphate
complex. While some of these crystals may be passed, accumulation
of the crystals can occur in the cat's bladder and urethra, resulting
in irritation of the lining of the bladder and urethral walls, making
them more prone to bacterial infection and microscopic bleeding.
Infection adds cellular debris to the crystal mix and may cause
a blockage of the urinary tubes, particularly in male cats. Due
to anatomic differences, primarily the smaller diameter of the urinary
tubes in male cats, the urinary tract of an afflicted male cat can
become completely blocked. The blocked cat may stop eating, vomit
and become increasingly agitated. Most worrisome, the condition
is immediately life-threatening. If a blocked cat does not receive
emergency medical attention to relieve the blockage, the cat may
die, in a matter of hours, from uremic poisoning and kidney failure.
Unfortunately, FUS is far too common. As many as 10% of all feline
admissions into a veterinary hospital are related to FUS. Most typically,
FUS has been observed in overweight cats that have been spayed or
neutered, and are between 2-6 years of age.
It has been observed that the struvite crystals associated with
FUS, which may lead to fatal blockage, generally form in more alkaline
cat urine. Consequently, a diet which causes the cat to excrete
alkaline urine predisposes the cat to FUS. In addition, a dietary
excess of magnesium and phosphorus will generally magnify the problem,
presumably by supplying the minerals needed to form struvite crystals
in alkaline urine. Hence, FUS can sometimes be avoided by switching
to a premium brand of cat food formulated to generate a slightly
acidic urine and which has a relatively low magnesium and phosphorous
Regrettably, however, cat owners frequently mistake the initial
symptoms of FUS for other problems, particularly constipation. To
the owner, the cat's frequent trips to the litter box (where the
cat may sit for longer periods of time) indicates that the cat is
constipated. Because the cat generally does not have a fever, and
appears otherwise normal, at least in the initial stages of the
disease, the owner too often assumes that the problem will pass.
Even if the cat cries out in pain, the cat owner may not realize
that a life threatening condition is imminent. Consequently, there
is a need for cat owners to be able to easily monitor their cats'
urine for the early signs of FUS, including the presence of an alkaline
pH and/or occult blood. (In contrast to red gross or frank blood,
occult blood cannot be visually detected by the cat owner. )
Moreover, once a cat has been afflicted with FUS, the cat frequently
becomes more succeptible to recurrence of the disease, even after
diagnosis and treatment with a diet formulated to generate a more
acidic urine. Owners of such cats need to be alerted to the continuing
signs of FUS, which can include occult or frank blood in the urine.
In addition, blood in the urine can be a sign of other feline diseases,
such as cystitis. Consequently, a convenient method of detecting
blood in the cat's urine can also alert the cat owner to the presence
of such other diseases, thereby ensuring that the cat gets prompt
As can be readily appreciated, however, it is difficult--if not
impossible--to get a cat to "give a sample" in which a
pH- or blood-detecting test stick could be dipped. As can also be
appreciated, particularly by cat owners, it would not be desirable
to collect the cat urine in the litter box for testing. For example,
replacing conventional litter (e.g. a processed, granular clay)
with a material that does not absorb urine might permit a test stick
to be dipped into the urine while it was still in the litter box;
but the cat owner would then be confronted with a messy testing
and disposal problem, particularly if frequent monitoring was sought.
Moreover, it would be difficult for the cat owner to avoid unsanitary
contact with the used cat litter, a contact made more particularly
undesirable if the urine is contaminated by bacteria from a bladder
Alternatively, the cat owner might be provided with a product to
be added to conventional, used litter. Such a product would react
to the presence of an alkaline pH or occult blood in the urine by
undergoing a color change, for example. This approach, however,
would be time-consuming and inconvenient, and would again expose
the cat owner to the risk of unsanitary contact with the used litter.
Further, any color changes which might occur would be very difficult
to see when such a product is added to conventional litter, e.g.,
clay, which already has a bluish hue and turns even darker when
wetted. Moreover, the cat owner would still confront the other problems
associated with conventional cat litter, including its heavy weight,
which makes transport of the litter difficult, and the task of filling
and cleaning the litter box. In addition, due to its "non-resilient"
nature, large and bulky packaging arrangements are required to accommodate
the desired volume of conventional litter.
The drawbacks of the foregoing proposals would only be multiplied
in situations outside the home where a large number of cats need
to be monitored; for example, in a pet shop, animal shelter and/or
at a veterinarian's office. Accordingly, there remains a need for
an inexpensive means for routinely and readily monitoring cat urine
for signs of FUS, cystitis and/or other feline diseases which are
indicated by a predetermined characteristic of the cat's urine,
such as a particular pH range and/or blood in the urine. There also
remains a need for a detection method which is convenient, easy
to use, and acceptable to both the cat and its caregiver.
SUMMARY OF THE INVENTION
The present invention provides a cat litter comprising a light-weight,
resilient paper product, which permits the cat owner or care giver
to detect feline diseases that are indicated by a predetermined
characteristic of the cat's urine. The cat litter comprises a plurality
of longitudinal paper strips, folded transversely into generally
zig-zag shapes. The paper strips are treated with a chemical indicator
selected to exhibit a noticeable color change when the treated paper
strips are wetted with cat urine having the predetermined characteristic
of the feline disease.
By observing color changes in the cat litter, the cat owner can
be readily alerted to the warning sign(s) of the disease. Critical
remedial action, such as a change in diet and/or an immediate visit
to the veterinarian, can then be taken by the cat owner.
Further, due to the zig-zag shapes of the paper strips, the litter
is resilient and can be compressed and then allowed to relax or
expand repeatedly. Hence, relatively large volumes can be compacted
into small and/or light-weight packages, which are convenient and
easy to use and carry. Also, the paper strips can be allowed to
relax or expand in an intertwining and interlocking manner, thereby
combining to form substantially a mass. The interlocking and intertwining
of the paper strips also prevents the cat from dragging pieces of
the cat litter out of its box, thereby keeping the cat owner's home
in a tidier condition.
The invention is particularly suited to detect FUS, conveniently
and inexpensively, even in its early stages and/or for the post-diagnosis
monitoring of cats with a history of FUS. When used to detect FUS,
the paper strips preferably comprise bleached, white Kraft paper,
and have preferably been treated with a pH indicator and/or an occult
The pH indicator is selected to exhibit a marked color change when
the treated paper is exposed to alkaline cat urine. Preferred examples
include bromocresol purple, phenol red, and chlorophenol red.
Similarly, the occult blood indicator is selected to exhibit a
marked color change when the treated paper is exposed to cat urine
comprising occult blood and/or its by-products (e.q., hemoglobin).
The occult blood indicator preferably comprises guaiac, benzidine,
ortho-tolidine, ortho-dianisidine, or other leuco-dyes, which produce
a blue color in the presence of microscopic blood and hemoglobin.
The cat litter preferably comprises a mixture of strips treated
with the pH indicator and strips treated with the blood indicator.
The indicators are preferably selected to undergo different color
changes when exposed to an alkaline pH or occult blood in the urine,
respectively. Then, when the cat uses the litter, the owner can
readily determine simultaneously if the cat's urine is alkaline
and/or contains blood.
Moreover, the presence of blood can alert the cat owner to the
possible presence of cystitis or other feline diseases. In addition,
gross red blood in the urine (another warning signal of feline disease)
can be easily observed by the cat owner, particularly when the treated
paper strips are manufactured from white Kraft paper.
The cat litter may also be treated with a sizing, in an amount
sufficient to permit the urine to roll off the strips initially
to the bottom of the cat litter, when the cat wets from the top
of the litter. Then, the urine is more gradually absorbed by the
strips, allowing them to become wetted from the bottom upwards.
Consequently, the cat can be kept drier and more comfortable, thereby
further encouraging use of the litter.
In addition, the paper cat litter is biodegradable and thereby
environmentally responsible, particularly when used in connection
with a disposable container, as hereinafter described. In the present
invention, the walls of the disposable container are preferably
coated with a biodegradable, water-repellant and urine-resistant
material. In addition, an absorbent paper sheet treated with an
antibacterial and/or anti-odor substance is preferably placed under
the treated paper strips, at the bottom of the container.
The present invention also provides a method for detecting feline
diseases, particularly FUS, in a cat, which are indicated by a predetermined
characteristic of the cat's urine. In this method, a web of paper
material is treated with a chemical indicator selected to exhibit
a marked color change when wetted by cat urine having the predetermined
characteristic. The treated paper is longitudinally cut into a plurality
of paper strips, which are folded transversely into generally zig-zag
The method is preferably employed to detect FUS. In this preferred
embodiment, the method comprises treating the paper strips with
a pH indicator and/or occult blood indicator, selected to exhibit
a marked color change upon contact with alkaline cat urine and/or
bloody urine, respectivley.
These and other features of the invention are fully described and
particularly pointed out in the claims. However, the particular
embodiments depicted and exemplified are only illustrative of the
range of ways by which the principles of the invention may be employed.
BRIEF DESCRIPTION OF THE DRAWINGS
In the drawings:
FIG. 1 is a perspective view of a disposable cat litter box containing
an embodiment of the resilient, paper cat litter of the invention,
wherein the cat litter box includes a container which is convertible
between closed and open conditions in which it respectively forms
a closed and open receptacle, the container being shown in the open
FIG. 2 is a perspective view of the cat litter box of FIG. 1 with
the container being shown in a partially opened condition;
FIG. 3 is a perspective view of the cat litter box of FIG. 1 with
the container being shown in the closed condition;
FIG. 4 is a partially cut-away perspective view of a different
cat litter box containing the resilient paper cat litter of the
invention, wherein the cat litter box includes a flat cover panel
enclosing the cat litter, and in which cat litter box the cat litter
is underlaid by an absorbent sheet of paper product that has been
treated with an antibacterial and/or anti-odor substance.
FIG. 5 is a partially exploded and cut-away perspective view of
the cat litter box of FIG. 4; and
FIG. 6 is a perspective view of a nested stack of six of the cat
litter boxes of FIG. 4.
DETAILED DESCRIPTION OF THE INVENTION
Referring now to the drawings in detail and initially to FIGS.
1 2 4 5 and 6 the feline disease detecting cat litter 20 of
the present invention is exemplified. As illustrated and described
in further detail herein, the cat litter 20 is preferably packaged
and used in a disposable cat litter box 10 which is convertible
between closed and open conditions. These preferred cat litter boxes
are disclosed in U.S. patent application Ser. No. 08/125310 and/or
PCT patent application Ser. No. PCT/US93/11085. However, it is also
contemplated that the cat litter 20 can be packaged and used with
other cat litter boxes and packaging materials.
In accordance with the invention, the cat litter comprises a resilient
paper product, which comprises a plurality of longitudinal paper
strips. The strips have been folded transversely into generally
zig-zag shapes, and treated with a chemical indicator selected to
undergo a marked color change when the treated paper strips are
wetted with cat urine having a predetermined sign or characteristic
of the feline disease.
When used to detect FUS, the paper is preferably treated with a
pH indicator and/or an occult blood indicator. More preferably,
the cat litter comprises a mixture of pH- indicating and occult
blood-indicating paper strips. The cat litter may also comprise
a mixture of treated strips and untreated strips.
The pH indicator is selected so that the treated strips exhibit
a noticeable color change when wetted with alkaline cat urine, which
is one of the primarily early warning signals of FUS. Upon observing
the color change, the cat owner can take prompt remedial action,
such as a change in diet and/or a visit to the veterinarian, thereby
averting serious illness or even death of the cat. (By selecting
a pH indicator which changes color in acidic cat urine, the present
invention can also be used to detect other feline diseases, which
are known to be characterized by acidic cat urine).
Normal cat urine has a pH value ranging between about 5.5 to about
6.6. Therefore, the selected pH indicator preferably exhibits a
prominent color change at or above a selected pH value of about
6.8. Preferred pH indicators include bromocresol purple, which rapidly
changes from yellow in acidic solutions to purple in alkaline solutions,
over a pH range of 5.2 to 6.8; chlorophenol red, which rapidly changes
from yellow (acid) to red (alkaline), over a pH range of 5.2 to
6.8; and phenol red, which also rapidly changes from yellow (acid)
to red (alkaline), over a pH range of 6.6 to 8.0.
The occult blood indicator is selected to exhibit a marked color
change in the presence of occult blood. Preferred indicators comprise
guaiac, benzidine, ortho-tolidine, ortho-dianisidine, or other "leuco-dyes,"
which turn various shades and intensities of blue, in the presence
of occult blood, hemoglobin, or other peroxidase-containing blood
components. (The peroxidase catalyzes the oxidation of the leuco-dye
by peroxide, resulting in the color change.)
The strips comprising the cat litter are formed from a paper material.
Preferably, the strips are made from thirty pound Kraft paper, which
preferably comprises bleached white Kraft paper. It is contemplated,
however, that other paper materials can be used, provided that the
material does not resist treatment with the selected indicator,
and is absorptive to cat urine. Also, when treated with the selected
indicator, the strips must undergo a noticeable color change when
wetted with cat urine having the predetermined sign(s) of the feline
Further, the paper material should be biodegradable, and thus environmentally
responsible. Moreover, it should be light-weight so as to provide
a cat litter which can be easily carried and used. Preferably, the
paper material is selected to provide a cat litter having a density
of between about 0.01 to about 0.001 ounces per cubic inch and more
preferably a density of approximately 0.035 inches per cubic feet
when compressed as when packaged in a cat litter container.
In addition, it should be recognized that the paper material for
forming the strips includes a natural resilience with a tendency
to remain in a straightened form and to resist folding or bending.
This principle can be readily observed by simply taking a small
sheet of Kraft paper and folding it in half. Initially, when pressure
is applied, the two halves of the sheet between the fold are pressed
together in close contact. When the pressure is released, however,
the fold has a tendency to relax or expand, thereby causing the
halves to angularly separate.
Due to the foregoing characteristics, the paper strips, when folded
transversely into zig-zag shapes, act like mini-springs, which can
be longitudinally compressed and allowed to relax or expand repeatedly.
Hence, relatively large volumes of the cat litter 20 of the present
invention can be compacted into small and/or light-weight packages,
which can be conveniently transported and stored. This feature provides
an additional significant benefit to the manufacturer, dealers,
and users of the cat litter of this invention.
Moreover, when allowed to relax or expand, the resilient zig-zags
can become intermixed and repositioned in an intertwining and interlocking
manner. Preferably, when the cat litter is in use, the strips have
been permitted to intertwine and interlock sufficiently to form
substantially a mass. The interlocking and intertwining prevents
the cat from dragging pieces of the cat litter out of its box, thereby
keeping the cat owner's home in a tidier condition.
Examples of suitable machines/methods for converting a continuous
web of paper material into the plurality of zig-zag shaped strips
comprising the cat litter of the present invention are disclosed
in U.S. Pat. Nos. 5088972; 5134013 and 5173352; and U.S. patent
application Ser. Nos. 07/861225 07/971046 and 08/153360. (All
of these patents/applications are assigned to the assignee of the
present invention.) In these machines/methods, a portion of the
continuous web of paper material is withdrawn and cut into a plurality
of strips by rotating sets of cutting discs, thereby forming a body
of such strips. The plurality of strips are advanced against a restricting
means acting on the body of strips in such a manner that the natural
resilience of the paper causes the paper strips to be folded into
generally zig-zag shapes, with substantially uniform adjacent and
opposite planar portions between the folds.
Using the preferred machines/methods, the tightness of the resulting
folds can be controlled by adjusting the speed at which the strips
advance against the restricting means. A slower speed generates
a tighter fold or crimp. Applicants have observed that tighter folds
permit the zig-zag strips to become more thoroughly interlocked
and intertwined. Thus, the speed can be regulated to provide a cat
litter having the desired degree of interlocking and intertwining.
The continuous web of paper material employed is commonly supplied
in a compact form, such as roll. Alternatively, as is disclosed
in pending U.S. Pat. No. 5387173 (assigned to the assignee of
the present invention), the disclosure of which is hereby incorporated
by reference herein, the web of paper material could be fan-folded
into a rectangular stack.
The machine/method for converting the web of paper material into
the zig-zag strips preferably incorporates a system for treating
the paper with the selected indicator. Examples of suitable machines/methods
for treating the paper strips with the indicator are disclosed in
pending U.S. application Ser. No. 08/153360. The preferred treatment
method comprises providing a continuous web of an untreated paper
material; withdrawing a portion of the web to thereby form a withdrawn
portion; applying the indicator in liquid phase to the withdrawn
portion of the paper material; and converting the treated withdrawn
portion into the plurality of zig-zag shaped strips. The preferred
treatment-applying device preferably includes a container or trough
which contains the indicator in the liquid phase, a roller which
is partially submerged within the liquid treatment and which contacts
the withdrawn portion, and a drive assembly which rotates the roller
and thereby transfers the liquid treatment from the container to
the withdrawn portion.
The drive assembly of the preferred treatment system may include
an adjustment mechanism which selectively varies the rotational
speed of the roller for selectively varying the amount of the liquid
treatment being transferred to the withdrawn portion. The speed
can then be adjusted as needed to treat the paper web with the indicator
for a time period sufficient to ensure that the resulting cat litter
produces a noticeable color change when later wetted with cat urine
having the predetermined characteristic of the feline disease. Also,
the rotational speed of the roller can be controlled to ensure that
the paper web does not become so moistened that it loses its integrity
or turns "mushy", thereby precluding the paper from being
folded into resilient zig-zag shapes.
The pH indicator, when applied in liquid form, preferably comprises
an aqueous solution. The indicator can be added to water (or another
liquid base) in either powdered or solution form. Suitable powdered
or liquid forms of phenol red, chlorophenol red and bromocresol
purple are available from the Aldrich Chemical Company, Milwaukee,
Wis. Preferably, phenol red is used as an aqueous solution containing
0.1 percent weight per volume. Preferably, chlorophenol red and
bromocresol purple are used as aqueous solutions containing 0.04%
weight per volume.
When the cat litter is prepared by moistening the paper with the
liquid phase indicator prior to folding the resulting strips into
zig-zag shapes, less pressure is generally required to initially
impart a folded memory to the treated paper material. Additionally,
when the folds relax, the angular separation between the folds is
to a lesser degree than that produced in the dry paper. Additionally,
because the separation is to a lesser degree, the folds tend to
be more stable and, as the paper dries, tend to retain a smaller
angle at the folds than would be accomplished over the same period
of time at folds formed in the drier sheet material. Thus, the preferred
system for treating the paper with the indicator provides a cat
litter comprised of strips having improved "springiness."
Hence, the degree of interlocking and intertwining of the strips
and the resilient properties of the cat litter can be enhanced.
Although the cat litter (when used to detect FUS) may contain paper
strips which have been treated with pH indicator only or with occult
blood indicator only, the preferred embodiment is a cat litter containing
a mixture of pH indicator-treated strips and occult blood indicator-treated
strips. The mixture preferably is a 50--50 mixture of indicator
strips; however, the ratio of indicator strips in the mixture may
vary according to which pH indicators and occult blood indicators
are used. It is also contemplated that cat litter mixtures may also
contain untreated paper strips. Regardless of the number or ratio
of indicator strips used, it is necessary that the resulting mixture
of paper strips be sufficient to provide a noticeable color change
of the treated strips, in the presence of alkaline cat urine and/or
cat urine containing occult blood. It is contemplated that mixing
of the indicator strips may take place at any time during or after
their manufacture, including mixing by the cat caregiver prior to
use by the cat.
Untreated paper litter strips are preferably also treated with
an odor-reducing or neutralizing agent. However, if treated paper
strips are used, any odor-reducing or neutralizing agent is preferably
present not in the strips themselves, but in the absorbent pad 132
which underlies the paper strips, in order to minimize any chemical
interaction between the treated strips and the neutralizing agent.
When used in either untreated strips or in the absorbent pad, the
odor-reducing or neutralizing agent is preferably present in a quantity
sufficient to reduce the level of volatile odorant compounds (primarily
ammonia generated by decomposing urine) in the cat litter 10 during
the time that it is made available for use by the cat. Preferred
odor-reducing agents are disclosed in U.S. Pat. No. 4938957 incorporated
by reference herein, and are available from Epoleon Corporation,
Tokyo, Japan under the product name Epoleon N-100-65-2 and which
contains the ingredients zinc phenolsulfonate, malic acid, diethanol
amine and water in a composition of 21% weight of solids per volume.
Additionally, the untreated or treated strips or the underlying
pad may also be treated with an antibiotic or antibacterial material,
such as neomycin. The quantity of antibiotic or antibacterial material
is sufficient to retard the growth of any bacterial species present
in such use, for a period of time before the cat litter reaches
a sanitarily unacceptable condition. The preferred antibiotic is
neomycin, in the form of neomycin sulfate, and is obtainable from
The Upjohn Company, Kalamazoo, Mich.
The paper material can also be treated with a sizing, such as starch,
in an amount sufficient to permit the urine to roll off the strips
initially to the bottom of the cat litter, when the cat wets from
the top of the litter. The cat urine is then more gradually absorbed
by the strips, allowing them to become wetted from the bottom upwards.
Consequently, the cat can be kept drier and more comfortable, thereby
further encouraging use of the litter by the cat. The amount of
sizing applied, however, should not be so great that it prevents
the cat urine from being absorbed into the paper, such that it collects
at the bottom of the cat box, thereby precluding the cat owner from
readily noticing the color changes indicated by alkaline urine or
occult blood, for example (and creating a messy disposal problem).
The amount of sizing applied also must not be so great as to preclude
absorption or adsorption of indicator during the liquid phase treatment
of the paper.
As previously indicated, the cat litter 20 is preferably packaged
and used in a disposable cat litter box which is convertible between
closed and open conditions. Accordingly, the cat box may be compactly
stored as a closed receptacle until ready for use, converted into
an open receptacle for use by the cat, and then converted back into
a closed receptacle for convenient and sanitary disposal.
In one preferred embodiment illustrated by FIGS. 1-3 (disclosed
in U.S. patent application Ser. No. 08/125310 and PCT patent application
Ser. No. PCT/US93/11085 the cat litter box comprises a container
10 which is convertible between a closed condition in which it forms
a closed receptacle (FIG. 3) and an open condition in which it forms
an open receptacle (FIG. 1). The conversion is accomplished by providing
the container 10 with appropriate sets of folding panels and appropriate
The container 10 is initially packaged and supplied in the closed
condition, with the cat litter 10 being enclosed within the closed
receptacle. When the container 10 is converted to the open condition,
the open receptacle confines the cat litter 20 while at the same
time permitting a cat access for interaction with the cat litter
The cat may then interact with the cat litter 20 until it reaches
a sanitarily unacceptable condition. Once the cat litter 20 reaches
a sanitarily unacceptable condition, the container 10 is converted
back into the closed receptacle to thereby enclose the sanitarily
unacceptable cat litter within the container 10. The container 10
and the sanitarily unacceptable cat litter enclosed therein, may
then be disposed of as a unit. In this manner, the often unpleasant
and unsanitary task associated with changing cat litter in conventional
boxes is eliminated.
The conversion is accomplished by the container 22 including a
set of panels and appropriate interconnections therebetween. Specifically,
when viewed in the open condition (FIG. 3), the container 22 comprises
a bottom panel 30 a front panel 31 a rear panel 32 two side panels
33 and four connecting panels 34.
When the container 22 is in the closed condition (see FIG. 1 ),
the panels 31-33 are in a horizontal orientation and form a closed
receptacle for the kitty litter 20. The closed receptacle has a
width W.sub.closed, a length 1.sub.closed, and a height h.sub.closed.
In the preferred embodiment, these dimensions are approximately
fifteen inches, eighteen inches, and one and a half inches.
When the container 22 is in an open condition (see FIG. 3), the
panels 30-34 form the open receptacle. The open receptacle has a
width w.sub.open which is equal to w.sub.closed, a length 1.sub.open
which is equal to 1.sub.closed, and a height h.sub.open which is
substantially greater than h.sub.closed. Specifically, the height
h.sub.open is approximately nine inches. Thus, the volume of the
container 22 when it is in the open condition (or the open receptacle)
is greater than when it is in the closed condition (or the closed
As is best seen in FIG. 1 the height of each of the side panels
33 (h.sub.closed -.sub.open) is preferably such that it equals approximately
half of the width w.sub.closed or w.sub.open. (Thus, in the preferred
container 22 the height of the side panels would be approximately
seven and a half inches.) In this manner, the free edges of the
side panels 33 abut when the container 22 is in the closed condition.
The kitty litter box 10 may additionally include an adhesive strip
36 for locking these edges together and securing the container 22
in the closed condition.
As is best seen by referring to FIG. 3 the cut-out 37 forms an
entrance-way into the open receptacle when the container 22 is in
the open condition. The rear panel 32 one of the side panels 33
the front panel 31 the other side panel 33 and the coupling panel
35 are arranged linearly adjacent to each other in this order. The
corresponding connecting panels 34 are arranged in a similar manner
below the panels 31-33.
The interconnections of the container 22 comprise panel-joining
hinges (i.e., hinges which join separate panels together) and panel-internal
hinges (i.e., hinges within a particular panel). The panel-joining
hinges include vertical fold lines 40 and 41. Four of these vertical
fold lines, namely fold lines 40 connect the rear panel 32 to the
adjacent side panel 33 this side panel 33 to the front panel 31
the front panel 31 to the other side panel 33 and the latter side
panel 33 to the coupling panel 35. The connecting panels 34 include
similar vertical fold lines 41 therebetween. As is best seen by
referring to FIG. 3 the fold lines 40 and 41 together form the
corner intersections of the container 22 when it is in an open condition.
The panel-joining hinges of the container 22 additionally comprise
horizontal fold-lines 42. Fold lines 42 are arranged in parallel
pairs along the upper and lower edges of the connecting panels 34.
Thus, each of the upper fold lines 42 joins the front/rear/side
panel 31/32/33 to the corresponding connecting panel 34 while the
lower fold lines 42 join the appropriate section of the bottom panel
30 to the corresponding connecting panel 34.
The panel-internal hinges of the container 22 comprise slanted
fold lines 44. Fold lines 44 extend from the bottom corners of the
front/rear panels 31 and 32 at an approximately 45.degree. angle
and separate each of the panels 31 and 32 into a middle portion
50 and outer portions 52. In the rear panel 32 the outer portions
52 are isosceles triangles and the middle portion 50 is a complementary
triangle. The portions on the front panel 31 are similar in shape
except that they are truncated by the cut-out 37. In the preferred
embodiment, the internal fold lines (not shown) are interrupted
by a semi-circular cut-out forming a semi-circular locking tab 55.
To convert the container 22 to the closed condition, the middle
portions 50 of the front/rear panels 31/32 the outer portions 52
of the front/rear panels 31/32 and the side panels 33 are positioned
in a horizontal orientation. Specifically, the outer portions 52
are folded over the middle portions 50 and the side panels 33 are
positioned over the outer portions 52. In this folding arrangement,
the middle portions 50 of the front/rear panels 31/32 extend inward
from the fold lines 42 at an approximately 90.degree. angle; the
outer portions 52 extend inward from the slanted fold lines 45 at
a 180.degree. angle and extend inward from the panel-joining folds
40 at a 180.degree. angle; and the side panels 33 extend inward
from the fold lines 42 at a 90.degree. angle. Thus, the side panels
33 form the top surface of the container 22 when it is in the closed
To convert the container 22 from the closed condition to the open
condition, the adhesive strip 36 is moved. (See FIG. 1) The side
panels 33 are then manually pulled upward and outward to an upright
vertical position. (See FIG. 2 which, while showing the container
22 only partially opened, best illustrates this concept.) This manual
pulling simultaneously unfolds the outer and middle portions 50
and 52 of the front/rear panels 31 and 32 and forces the front/rear
panels to a vertical position. When the panels 31-33 are in an upright
vertical position, the container 22 forms the open receptacle to
thereby permit access to the fresh kitty litter 20. A cat may then
interact with the fresh kitty litter 20 by entering the kitty box
10 through the cut-out 37. If the container 22 includes locking
tabs 55 they may be maneuvered to lock the panels 31-33 in the
upright vertical position.
Once the fresh kitty litter 20 reaches a sanitarily unacceptable
condition, the container 22 may be converted back into the closed
receptacle by releasing the locking tabs 55 and manually pushing
the side panels 33 inward and downward. This manual pushing simultaneously
folds the outer and middle portions 50 and 52 of the front/rear
panels 31 and 32 and forces the front/rear panels to a horizontal
position. The adhesive strip 36 (or another similar strip) may then
be used to resecure the free edges of the side panels 33 thereby
sealing the sanitarily unacceptable kitty litter within the container
22. The container 22 and the sanitarily unacceptable kitty litter
enclosed therein, may then be disposed of as unit.
The container 10 is made of material which is sufficient strength
to function as a self-standing carton in its open condition and
of sufficient flexibility to convert between the open and the closed
condition. Preferably, the container 10 is made of a paper material
so that it is biodegradable and recyclable, and thus environmentally
responsible. The container 10 should also be made of a light-weight
material, whereby the box's weight and size parameters do not nullify
its convenience in connection with disposal.
More preferably, the container 10 is made of corrugated cardboard
as this material economically provides the desired characteristics.
In the preferred embodiment, the container 10 when empty, weighs
approximately one pound, and the completed cat litter box (i.e.,
the cat litter 20 and the container 10 enclosing the litter) weighs
approximately one and one-half pounds. By way of comparison, applicants'
testing has proven that if the preferred container 10 was filled
with a conventional clay litter, it would weigh approximately from
eight to nine pounds. Also by way of comparison, applicants' testing
has proven that if the preferred container 10 was filled with "scoopable"
clay litter, it would weigh approximately from six to eight pounds.
(Applicants note that this comparison may be somewhat conservative
because it may actually require a greater volume of clay litter
and/or "scoopable" litter to replace the resilient paper
cat litter 20.) Applicants contemplate a depth of their fresh, resilient,
low-density cat litter of about one and one-half inches, whereas
conventional clay kitty litters call for a depth of two inches.
In the above described comparative testing, applicants' containers
were filled only to a depth of one and one-half inches with, respectively,
the fresh cat litter of the present invention and clay cat litter.
In another preferred embodiment illustrated in FIGS. 4-6 (and disclosed
in U.S. Pat. application Ser. No. 08/125310 and PCT patent application
Ser. No. PCT/US93/11085 the shape of the container allows multiple
containers to be nestably stacked. In this second preferred embodiment,
the length and width of the bottom of a first container 110 fits
easily within the open space above the cat litter 20 defined by
the portion of the walls extending above the cover panel 160 of
a second, lower container 110 whereby the bottom of the first container
110 preferably actually rests upon the cover panel 160 and partially
within the walls of the lower container 110 with which it is nested.
Thus, while the container 110 may have a height of, e.g., four inches,
when the container is nestably stacked in accordance with the invention,
the container contributes only about one and three-quarters inch
to the total height of a nested stack of such containers.
In this embodiment of the invention, to convert the disposable
cat litter box between the open and closed conditions, the user
simply removes or replaces top panel 160 within the receptacle formed
by panels 131 and 133. When in the closed condition, top panel 160
will be in contact with the cat litter 20 and will resiliently
compress cat litter 20 somewhat. The compactability, in conjunction
with the stackability and nestability of the preferred cat box,
combine to provide unexpected benefits in cost savings and space
savings during storage and shipping.
As illustrated in FIG. 4 the preferred embodiment also includes
an absorbent, anti-bacterial pad 132 positioned at the bottom of
the container 110. The preferred absorbent pad has approximately
28 pound weight, is unlined, and has been treated with a broadspectrum
antibiotic or antibacterial material such as neomycin. The most
preferred absorbent paper material 132 is 28 pound Shoksorb with
neomycin, available from Kieffer Paper Mills, Inc. Brownstown, Ind.
The pad is also preferably treated with an odor-reducing or neutralizing
agent, including those previously described herein. (Although not
specifically shown in these drawings, the cat litter of FIGS. 1-3
also preferably includes an absorptive pad treated with anti-bacterial
and odor-neutralizing agents and positioned at the bottom of the
Further, the walls of the preferred, disposable cat litter box
are preferably coated with a biodegradable, water-repellant and
urine-resistant material. A preferred material is Michelman "42
KR", but other suitable materials are also available from Michelman,
Incorporated, Cincinnati, Ohio.
Applicants contemplate that the cat litter of the invention, alone
or in conjunction with the preferred disposable cat litter boxes,
may be used in the homes of cat owners to monitor feline diseases,
particularly FUS, conveniently and inexpensively. Also, applicants
contemplate that the cat litter would be advantageous in situations
where a large number of cats need to be monitored for FUS, such
as at veterinarian offices or kennels, animal shelters and/or pet