Abstrict A cat litter composition, which is absorbent, odorless, trackless
and biodegradable, comprising about 60-94% by weight absorbent,
about 1-35% by weight gypsum, and about 3-12% by weight water. The
composition is pelletized so that it may easily be disposed of by
flushing it down the toilet. This is particularly desirable when
the composition is used as a cat litter.
Claims What is claimed is:
1. A composition which is useful as a cat litter comprising about
60-94% by weight paper as an absorbent, about 1-35% by weight gypsum
as a neutralizing agent, and about 3-12% by weight water.
2. The composition of claim 1 wherein said paper comprises about
80-94% by weight and said gypsum comprises about 1-7% by weight.
3. A method of making a cat litter composition comprising:
a. mixing shredded or powdered paper with 3-12% by weight water
and 1-35% by weight gypsum until substantial uniformity is achieved,
and
b. pelletizing the mixed paper, gypsum and water.
4. The method of claim 3 wherein the water includes sufficient
soap to maintain the pellets in pelletized form.
5. A composition useful as a cat litter comprising about 60-90%
absorbent comprising one or more of clay and paper, about 1-35%
by weight gypsum and about 3-12% by weight water.
6. The composition of claim 5 wherein the absorbent is clay.
7. The composition of claim 5 wherein the absorbent is clay and
paper.
Description BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a novel composition which may
primarily be employed for animal or cat litter, but can also be
employed as plant mulch or a grease and oil absorbent.
2. Description of the Prior Art
Many cat litter compositions are available on the market which
comprise an absorbent, a deodorant and sometimes a coloring agent
and disinfectant agent. Absorbents such as clay, fuller's earth,
cotton, wool, linen, paper, lime, diatomaceous earth, pumice, sand,
wood chips, vermiculite, peat and alfalfa are employed for cat litter
compositions. These absorbents typically comprise approximately
5-40% by weight of the cat litter. The following patents disclose
a cat litter composition comprising gypsum and paper or other absorbents.
U.S. Pat. No. 4090470 to Williams teaches making deodorant by
shaping and sizing an absorbent material to fit within a circular
holder, and saturating the absorbent material with a deodorizing
solution. One of the absorbent materials listed in the patent is
paper. Another material which may also be employed, not as an absorbent,
but as a carrier, is gypsum. The deodorant compositions are primarily
either aluminum sulfate with a fragrance, or aluminum chloride with
a fragrance.
The absorbent material saturated with the deodorant is positioned
in a circular holder under the litter box for emitting deodorant
vapors about the area surrounding the litter box.
This reference has several deficiencies in that the litter box
is designed to employ a commercially available cat litter, in addition
to the self-made deodorizer, thus yielding a product which is expensive
and is not adaptable to other uses, like plant mulch.
U.S. Pat. No. 4123489 to Kelley teaches a method for pelletizing
waste paper products, and mixing the pellets with portland cement
and gypsum to form a light weight insulating concrete which can
be cast or sprayed into place. This reference also describes the
use of the pelletized paper, by itself, as a plant mulch or potting
soil.
This patent is not employed as an animal or cat litter. Furthermore,
the gypsum is not uniformly incorporated into the pelletized paper,
but is merely employed as a coating or binder along with the portland
cement to make a light weight cement.
U.S. Pat. No. 4163674 to Been teaches a process for making a
synthetic liquid absorbent which may be employed for cat litter.
Specifically, used newspaper is pulped with water and gypsum, dried
and granulated. The composition contains 59 to 79% by weight hydrated
gypsum in the form of plaster, 0.9% to 3.7% by weight paper and
29.5% to 37% by weight water.
This reference has several deficiencies including the fact that
the composition is not pelletized. Furthermore, the composition
contains a large amount of gypsum which is granulated into a powder
which forms paw prints around the house by the animal user. Also,
consumers prefer a product which is easily disposed of by flushing
the toilet. With a high percentage of gypsum, the product is dense
and practically unflushable, unless multiple flushes are employed.
U.S. Pat. No. 4278047 to Luca teaches an absorbent for animal
excreta comprising vermiculite, gypsum and water, and optionally,
a surfactant to aid in wetting the vermiculite and a disinfectant.
After blending the above components with a composition, the composition
is dried to drive off all the water. Thus, the primary components
comprise vermiculite and gypsum while the optional components comprise
disinfectant and surfactant. The final composition contains 40-66%
by weight gypsum, 20-33% by weight vermiculite. The vermiculite
can be replaced with some clay. Consequently, 0 to 33% by weight
clay can be employed as a replacement for some of the vermiculite.
This reference also contains several deficiencies including the
fact that the composition contains a large amount of gypsum which
adheres to the user who leaves paw prints around the house. This
characteristic is further aggravated by the vermiculite which is
a very light weight material, and easily clings to the paws and
fur of animals. Lastly, both vermiculite and gypsum are not biodegradable
and therefore they do not easily break down at a sewage treatment
plant.
Because of the various differences of the above products, there
currently exists a need for an animal or cat litter which is odorless
(and thus natural smelling to the animal user), trackless, biodegradable
and flushable.
SUMMARY OF THE INVENTION
The present invention comprises a cat litter composition which
is absorbent, odorless, dustfree, trackless, flushable and biodegradable.
The ternary composition includes water, gypsum and an absorbent
comprising paper and/or clay.
Although the primary use of the composition is intended as a cat
litter, it can also be employed as a grease and oil absorbent, or
plant mulch.
The present invention comprises a composition containing about
60-90% by weight absorbent, about 1-35% by weight gypsum and about
3-12% by weight water. Preferably the composition comprises about
80-94% by weight cellulose as an absorbent, about 1-7% by weight
gypsum, and about 3-12% by weight water.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The composition of the present invention is manufactured primarily
with three ingredients: water, an absorbent comprising clay and/or
cellulose, and gypsum. The water employed in the composition is
generally tap water, but may be any source of water, so long as
the water does not contain minerals or other elements which give
an odor to the water. Furthermore, an excessively acidic water would
chemically attack the cellulose, while an excessively basic water
would irritate the dermis of the animal. Accordingly, the water
should be neutral with a pH of about 7 to avoid the above drawbacks.
Gypsum is the naturally occurring mineral, CaSO.sub.4.2H.sub.2
O, which is primarily used in making plaster of Paris--CASO.sub.4.1/2H.sub.2
O, pigment for paint, or as a component in cement. Additionally,
gypsum may be used in a plant mulch because it is slightly acidic
and neutralizes alkaline soil, such as those containing alkali carbonates.
Lastly, without wishing to limit the present invention to any specific
theory, it is theorized that gypsum reacts with urea, which is the
key component in urine, to form a urea sulfate salt. Thus, gypsum
acts to prevent urea from breaking into its components, one of which
is ammonia, so that when gypsum is employed in an animal litter
composition, it prevents the typical urine-ammonia smell.
One of the most abundant and economical sources of cellulose is
recycled paper. Paper has several desirable characteristics, such
as being biodegradable, very absorbent, and capable of being easily
disposed of by flushing it in a toilet.
The preferred composition is generally made by shredding old paper,
such as newspaper, magazines, etc., grinding it into a powder, and
adding sufficient water to pelletize the paper (generally about
3-12% by weight water) while simultaneously adding 1-7% by weight
gypsum. The powdered paper, water and gypsum are mixed with substantial
uniformity and then pelletized under high pressure as is known in
the industry. The hardness of the pellets can be controlled to some
extent by the thickness of the pellet die. The thicker the die,
the harder the pellet; the thinner the die, the softer the pellet.
If a thick die is employed, more pressure is required to pelletize
the composition. If a thin die is employed, less pressure is required,
but the pellet is soft and thus the pellet has a greater tendency
to disintegrate into powder or dust. However, this can be minimized
by employing a binder, such as soap, in the composition so that
the soft pellets remain in pelletized form.
CAT LITTER
When the composition of the present invention is to be employed
as a cat litter, either clay and/or paper can be used as the absorbent.
The amount of clay or paper employed in the cat litter composition
depends upon the amount of gypsum employed. Basically the composition
includes an amount of gypsum with the balance being clay or paper,
except that sufficient water is employed to assure adequate mixing
and sufficient green strength to enable the composition to be pelletized.
The amount of gypsum employed can range from 1-35% by weight. Using
more than about 35% by weight gypsum causes the composition to easily
break down during use, from pellet form to a fine powder. The powder
is then spread throughout the home by the animal user. Using less
than about 1% by weight gypsum is insufficient to adequately react
with the urine to neutralize the odor.
The preferred composition contains about 1-7% by weight gypsum.
This is the preferred range because it has been discovered that
this amount of gypsum is sufficient to neutralize the odor when
the absorbent is spent. Cellulose is the preferred absorbent, and
in particular, paper is the preferred cellulose because it is more
economical and appears capable of absorbing more animal waste.
The above composition may be employed as cat litter by pouring
the pelletized composition into a litter pan at a depth of 1/2 to
3 inches.
The above composition is particularly useful as a cat litter for
the following reasons. Urine has as it chief components water, salt
and urea. It is the ammonia smell of urea that all commercially
available cat litters seek to mask, neutralize or otherwise supress.
Ammonia is given off as a gas whenever urine starts to chemically
decompose, as it does shortly after discharge from all amimals.
As stated previously, it is theorized that gypsum chemically reacts
with urea to form the salt urea-sulfate, which does not chemically
decompose at room temperature and pressure. Consequently, the odor
of urine is eliminated, not by using fancy perfumes or masking agents,
but by using gypsum.
Because the cat litter is pelletized, it is trackless, dustless
and flushable (pellets don't possess the tendency to clog like toilet
paper). Conventionally, pelletizing would be undesirable in most
cat litter applications because the interior of the pellets are
not contacted with and exposed to the animal waste. Consequently,
most cat litter is in the form of a fine powder (which is why they
are dusty and track-up the home), which increases the surface area
of the absorbent and other materials, so that more of the cat litter
contacts the waste and thus it is utilized to its utmost efficiency.
However, pelletizing is not a detriment to the present invention.
In addition to the desirable characteristics of trackless, dustless
and flushability, which pelletizing achieves, the present invention
possesses a characteristic which overcomes the prior art problems
of inefficient surface contact between the interior of the prior
art pellets and the animal waste.
Urea has the characteristic of softening paper when contacted with
it. Hence, as the animal uses the cat litter, pellets soften, expand
and expose the fresh interior of the pellet so that more absorbent
and gypsum will contact the waste.
As the pellet expands, the physical characteristics of the pellets
change, such that they become more flushable in the toilet. This
results directly from the fact that the pellets absorb approximately
twice their own weight of animal urine, giving the pellets a density
more like that of water itself (urine is approximately 95% water),
so that the pellets flow more easily with the water in the toilet
when the toilet is flushed.
Another feature of the present invention is that paper, which comprises
60 to 94% of the invention is completely biodegradable. Thus, upon
arrival of the pellets at a sewage treatment plant, the pellets
have generally completely disintegrate in the sewage water.
PLANT MULCH
The composition may be employed as a plant mulch by mixing it with
soil, particularly when paper is the sole absorbent. The paper in
the composition acts as a moisture retainer to maintain adequate
moisture to the plant during periods between watering or raining.
Furthermore, the paper is penetrable by the roots of plants, which
allows the plants to obtain the mineral calcium sulfate (gypsum).
Also, gypsum has the ability to neutralize alkaline soil, particularly
alkali carbonates, since it is slightly acidic. Lastly, because
the composition is biodegradable, it completely disintegrantes into
the mineral and basic organic components.
GREASE AND OIL ABSORBENT
The composition is also useful as an absorbent of grease and oil
by spreading the composition on the oil and/or grease. In this use,
the preferred absorbent is paper because it appears to absorb more
grease and oil than clay. While paper absorbs the oil and grease,
the mineral gypsum, which is slightly acidic, acts as a mild acid
cleaner to aid in substantially totally removing the oil or grease. |