Abstrict A dustless cat litter including a wetting additive to agglomerate
dust to litter ingredients and promote hydration. Exemplary wetting
additives are water soluble, anionic, nonionic, amphoteric or synthetic
surfactants, surfactant mixtures, soaps or synthetic detergents
which are applied to the litter ingredients to bind dust and fines
contained in the mixtures. A masking fragrance, neutralizer or attractant
may be admixed with the surfactant. Exemplary hydrating cat litter
or additive mixtures, which solidify upon contact with liquids to
encapsulate pet waste matter, include a granulated base material
(e.g. whole or coarse ground agricultural grains, pulse crops, clay
granules or mixtures thereof), a gluten containing material (e.g.
semolina or ground wheat) and may include sodium bicarbonate and/or
a carrier bound fragrance. A quantity of surfactant on the order
of 1/2 to 7 oz. per 10 pounds litter containing 5% to 10% fines
is applied to the ingredients during blending of the mixture.
Claims What is claimed is:
1. A cat litter composition comprising:
a) a granular base comprising a particulate sized in the range
of a 8 to 80 mesh;
b) a granular, gluten containing media, wherein the granularity
of the gluten media is selected to upon mixing with the base provide
a substantially homogeneous suspension of the gluten media within
a quantity of said base; and
c) a wetting additive applied to said base and gluten media to
agglomerate dust and fines contained in said base and gluten media
with said base and gluten media, wherein said wetting additive promotes
attraction of liquid animal waste to said gluten media, and wherein
said litter composition reacts in the presence of liquid containing
animal waste to bind the animal waste into hardened, biodegradable
clumps of animal waste, base and gluten media.
2. A cat litter composition as set forth in claim 1 wherein said
wetting additive is selected from a class including anionic, nonionic,
amphoteric or synthetic surfactants; soap; or synthetic detergents.
3. A cat litter composition as set forth in claim 2 wherein said
anionic surfactants are selected from a class containing lauryl
polyglucose, sodium laureth sulfate, TEA lauryl sulfate and sodium
lauryl sulfate.
4. A cat litter composition as set forth in claim 2 wherein said
nonionic surfactant is selected from a class including nonoxynol
1-10.
5. A cat litter composition as set forth in claim 2 wherein said
wetting additive includes a liquid deodorizer.
6. A cat litter composition as set forth in claim 5 wherein said
wetting additive includes a liquid animal attractant scent.
7. A cat litter composition as set forth in claim 1 wherein said
wetting additive is applied in a 0.1% to 20% solution by weight
of wetting additive to water, and wherein the additive is applied
at a concentration in the range of 1/2 oz. to 7 oz. per 10 lbs of
litter mixture.
8. A cat litter composition as set forth in claim 1 wherein said
base comprises cracked wheat.
9. A cat litter composition as set forth in claim 8 wherein said
gluten containing media comprises middlings of hard wheat.
10. A cat litter composition as set forth in claim 9 wherein said
hard wheat comprises durum wheat.
11. A cat litter composition as set forth in claim 1 wherein said
gluten containing media is sized in the range of a 20 to 80 mesh.
12. A cat litter composition as set forth in claim 1 wherein said
base comprises an agricultural material selected from a class including
whole or coarse ground wheat, rice, barley, corn, beans, rice, sunflower,
beans, oats, and flax.
13. A cat litter composition as set forth in claim 12 wherein the
class of base materials includes clay and by-products of agricultural
processing including hulls, husks, shells, peels, and cobs.
14. A cat litter composition as set forth in claim 1 including
a deodorizer.
15. A cat litter composition comprising:
a) a granular agricultural grain base particulate sized in the
range of an 8 to 80 mesh; and
b) ground wheat middlings sized in the range of a 20 to 80 mesh,
wherein the wheat mixed with the base to a substantially homogeneous
suspension;
c) a surfactant applied to said base and wheat to agglomerate dust
and fines contained in said base and wheat, wherein said surfactant
promotes attraction of liquid animal waste to said wheat, and wherein
said litter composition reacts in the presence of liquid containing
animal waste to bind the animal waste into hardened, biodegradable
clumps of animal waste, base and wheat.
16. A cat litter composition as set forth in claim 15 wherein said
surfactant is selected from a class including anionic, nonionic,
amphoteric and synthetic surfactants or mixtures thereof.
17. A cat litter composition as set forth in claim 16 wherein said
anionic surfactants are selected from a class containing lauryl
polyglucose, sodium laureth sulfate, TEA lauryl sulfate and sodium
lauryl sulfate.
18. A cat litter composition as set forth in claim 16 wherein said
nonionic surfactants is selected from a class including nonoxynol
1-10.
19. A cat litter composition as set forth in claim 15 wherein said
surfactant includes a liquid deodorizer.
20. A cat litter composition as set forth in claim 15 wherein said
surfactant is applied in a 0.1% to 20% solution by weight of surfactant
to water, and wherein the surfactant solution is applied at a concentration
in the range of 1/2 oz. to 7 oz. per 10 lbs of litter mixture 8
containing 2% to 10% fines.
21. A cat litter composition comprising:
a) a granular base particulate comprising hard wheat sized in the
range of an 8 to 80 mesh; and
b) wheat middlings sized in the range of a 20 to 80 mesh, wherein
the wheat middlings are mixed with the base to a substantially homogeneous
suspension;
c) an anionic surfactant solution of 0.1% to 20% solution by weight
of surfactant to water, wherein said surfactant is selected from
a class containing lauryl polyglucose, sodium laureth sulfate, TEA
lauryl sulfate and sodium lauryl sulfate applied to said base and
gluten media to agglomerate dust and fines with said base and gluten
media, wherein the surfactant solution includes a deodorizer, wherein
the surfactant solution is applied at a concentration in the range
of 1/2 oz. to 7 oz. per 10 lbs of litter mixture, and wherein said
litter composition reacts in the presence of liquid containing animal
waste to bind the animal waste into hardened, biodegradable clumps
of animal waste, base and wheat middlings.
22. A cat litter composition comprising:
a) a granular base, and a granular, gluten containing media, wherein
the granularity of the gluten media is selected to upon mixing with
the base provide a substantially homogeneous suspension of the gluten
media within a quantity of said base; and
b) a wetting additive applied to said base and gluten media to
agglomerate dust and fines contained in said base and gluten media,
wherein said wetting additive promotes attraction of liquid animal
waste to said gluten media, and wherein said litter composition
reacts in the presence of liquid containing animal waste to bind
the animal waste into hardened, biodegradable clumps of animal waste,
base and gluten media.
Description BACKGROUND OF THE INVENTION
The present invention relates to cat litters and, in particular,
to a biodegradable, scoopable cat litter which has been improved
to be dustless.
Pet owners and particularly urban cat owners have numerous concerns
pertaining to the care and maintenance of their pets. An ever present
concern is collecting and disposing of animal wastes. A secondary
concern is masking related odors, pending disposal.
For cat owners, the predominate mechanism for collecting and disposing
of the wastes is a so called "cat litter". Typically,
the cat litter is contained in a "litter box" that is
placed about the residence of the pet owner and where the cat over
time becomes accustomed to urinating and defecating. The liquids
of the feces and urine are absorbed by the cat litter, which is
periodically cleaned or discarded.
Commonly used litters provide a base material of clay, sand, gravel,
sawdust or wood chips. Deodorants or masking scents are frequently
added to the base material to mask any odor, pending collection.
Such deodorizers can be added directly to the particulate or be
impregnated into an absorbent carrier. Depending upon the aroma
and, if the cat is being trained to use an odoriferous mixture,
the cat may either accept or reject the litter.
Another litter is a so called "scoopable" litter. Such
litters typically are comprised of a clay base and to which a deodorizer
may be added, along with a hydrophilic material. The hydrophilic
material reacts with the water in the urine and fecal matter to
coalesce and produce clumps of litter where the animal has urinated
or defecated. These clumps can be scooped from the container and
disposed of along with any solid feces. A difficulty encountered
with scoopable litters is that a relatively soft or fragile clump
of waste matter is formed with the hydrophilic action.
With subsequent use of the container by the same or multiple cats,
the cats frequently break and remix the clumped matter into the
litter, unless the pet owner regularly cleans the litter box. With
any re-mixing of the waste matter, the pet owner is faced with the
same problems as with a non-scoopable litter. For example, should
the cats have worms or other digestive tract parasites, any re-mixing
of the waste matter re-releases the parasites, which can spread
amongst the cats and even possibly to other pets.
Another difficulty is that cats tend to exhibit a preference for
certain litters. Once trained to use one litter, a cat may reject
another, even if offering improvements.
A further difficulty of clay based litters arises from disposal
by pet owners into community sewer systems. That is, many pet owners
flush the used litter or clumped fecal matter into their toilet.
Because clay is not susceptible to decomposition, the particles
can collect and obstruct the plumbing and sewage system conduits.
The problem is of special concern in large municipalities or metropolitan
areas. Preferably, all the litter ingredients should comprise materials
which decompose in a relatively short time.
U.S. Pat. Nos. 5216980 and 5361719 which have issued to applicant,
disclose litter additives and mixtures that have solved many of
the foregoing difficulties.
Various pelletized, absorbent litters, using some similar ingredients
to those of applicant, and related manufacturing processes are also
described at U.S. Pat. Nos. 3983842; 4206718; 4217858; 4341180;
4519340; 4571389; 4883021; 5100600; Japan Patent No. 94043;
and European Patent No. 76122.
In spite of the improvements provided by applicant's litter additives
and mixtures, a problem common to all litters and shared by all
manufacturers and pet owners is the dust or fines present in the
litter mixtures. During mixing and packaging, air filtration equipment
can be used to collect and filter the dust. Such measures are principally
implemented to protect the workers. The mixture, however, is not
treated to remove the dust present in the ingredients.
Once the packaged mixture is opened and dispensed into the litter
box, the trapped dust is released into the pet owner's home. With
normal agitation of the litter, during cleaning and use by the pet,
the dust is continually released. Many pet owners have expressed
displeasure over the lack of a dustless litter.
Accordingly, applicant has developed further improved, dustless
litter and litter additive mixtures which produce relatively hard
clumps of encapsulated animal waste that do not break up with continuing
use of the litter by one or more cats. Desirably, the mixtures are
dust free, the ingredients are biodegradable and present no health
risks to the cat or pet owner, and promote hydration. The mixtures
may include fragrances for masking or neutralizing odors and/or
attracting the cat to minimize rejection of the litter.
SUMMARY OF THE INVENTION
It is accordingly a primary object of the present invention to
provide a dustless, biodegradable mixture.
It is further object of the invention to provide a dustless, biodegradable
cat litter mixture including a hydrophilic media, which encapsulates
and produces a strong, stable clump upon exposure to urine and fecal
matter.
It is a further object of the invention to provide a cat litter
including a biodegradable, hydrating additive media having a relatively
high gluten concentration and capable of permanently encapsulating
animal waste, particularly urine, into a strong stable clump.
It is a further object of the invention to provide a cat litter
including a dust inhibitor which agglomerates and binds any dust
or fines in the mixture ingredients to larger ingredient particles
without affecting the hydrating media.
It is a further object of the invention to apply an additive solution
of an anionic, nonionic, amphoteric or synthetic surfactant, surfactant
mixture, or a fatty acid based soap or detergent to the litter ingredients
to bind dust and fines contained in the mixture.
It is a further object of the invention to admix a masking fragrance
or neutralizer with the surfactant or carrier that is admixed with
the litter.
It is a still further object of the invention to admix a fragrance
having an attractant or "cat nip" quality to the surfactant
or a carrier that is admixed with the litter.
It is a further object to suspend the hydrating media (e.g. a gluten
containing material, such as semolina or ground wheat) in a base
material (e.g. coarse ground agricultural grains, pulse crops, clay
granules or mixtures thereof) and to coat the ingredients with a
liquid anionic or nonionic surfactant.
Various of the foregoing objects and advantages are achieved in
the biodegradable cat litter mixture of the present invention. In
a presently preferred mixture, the active clumping ingredient comprises
quantities of semolina ground to a 20 to 80 mesh.
The semolina is suspended in an organic, base material or mixture
of base materials ground to an 8 to 80 mesh, for example, whole
or coarse ground grains or pulse crops (e.g. wheat, corn, barley,
rice, sunflower or beans) or by-products of agricultural processes
(e.g. corn cob, orange peels, peanut shells, hulls, husks, wood)
or shredded and dried matter (e.g. paper or grass). The mixture
produces a scoopable, biodegradable litter which is capable of decomposition
upon disposal.
A wetting additive or inhibitor comprising a 0.1% to 20% solution
by weight of an anionic, nonionic, amphoteric or synthetic surfactant
to water is applied to the litter mixture. The inhibitor also promotes
hydration. The inhibitor is applied by injection at a concentration
in the range of 1/2 oz. to 5 oz. per 10 lbs of litter mixture containing
2% to 10% fines. The inhibitor is a wetting agent that agglomerates
dust and fines smaller than the ingredient nominal mesh size in
the mixture to the larger particles. The inhibitor exhibits a viscosity
in the range of 10 to 50 SAE.
Exemplary anionic surfactants are lauryl polyglucose, sodium laureth
sulfate, TEA lauryl sulfate and sodium lauryl sulfate. Exemplary
nonionic surfactants are a nonoxynol (1-10). Other inhibitors may
comprise a fatty acid based material, such as a soap or synthetic
detergent. Concentrations of other additives may be included to
stabilize the inhibitor from mold etc. and promote shelf life of
the litter.
A deodorizer, scent neutralizer, masking fragrance, attractant
fragrance or mixtures thereof can be admixed with the inhibitor
and a nonionic surfactant component to facilitate mixing. Quantities
of sodium bicarbonate and/or a neutralizer/fragrance/attractant
impregnated carrier, such as ground corn cob, may be added as desired.
The litter composition is biodegradable and not harmful to the animal's
health.
Still other objects, advantages and distinctions of the invention
will become more apparent from the following description with respect
to the appended drawings. Variously considered modifications and
improvements are described as appropriate. The invention should
not be strictly construed from the disclosure, but should be interpreted
in view of the following appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an isometric drawing showing a cat in relation to a typical
litter box containing the inventive cat litter composition.
FIG. 2 shows a flow diagram for preparing the biodegradable cat
litter of the invention.
FIG. 3 shows a chart from which preferred concentrations of dust
inhibitor can be derived.
FIG. 4 shows a cross section view of apparatus used to admix and
blend the litter ingredient mixtures of the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1 depicts a cat 2 which is shown in relation to a typical
"litter box" or container 4 for a cat litter 8. The container
4 can be of any construction or shape and is preferably liquid impermeable.
The container 4 is normally sized in a range of 14 to 20 inches
by 20 to 32 inches and provides a sidewall height sufficient to
accommodate a minimal litter depth of two to four inches.
The volume of the container 8 is typically selected to contain
a sufficient quantity of litter material to accommodate a preferred
cleaning cycle established by the pet owner. Additional sidewall
clearance is preferably provided to permit the cat 2 to cover the
waste matter by pawing adjacent litter 8 over the waste, without
undue spillage onto the surrounding floor.
The pawing and digging of the pet mechanically mixes the litter
8 to insure the production of strong, stable clumps of waste matter
6. The hardened clumps 6 are stable and readily removed with periodic
cleaning and straining of the litter 8. The clumps 6 are preferably
removed to a plastic bag and discarded with the household garbage.
U.S. Pat. Nos. 5216980 and 5361719 disclose litter mixtures
and litter additives comprised of natural ingredients which produce
stable clumps 6. The mixtures at U.S. Pat. No. 5361719 are particularly
biodegradable.
Each litter mixture 8 preferably includes a gluten based active
ingredient, such as semolina, which provides the desired clumping
action. Unfortunately, such mixtures are disposed to containing
quantities of fines or dust like particulates which are released
to the pet owner's residence with the initial dispensing and subsequent
agitation of the litter 8.
Advantageously, the litter mixtures 8 described below have been
improved to permit the above agitation without releasing dust and
trapped fines to the pet owner's residence. The mixtures 8 are also
biodegradable, unless mixed with a clay based media.
With attention to FIG. 2 the base material 10 of the presently
preferred and improved litters 8 comprise a liquid permeable, biodegradable
material, selected from a number of organic materials. The decomposition
period of the material 10 desirably should be relatively short.
Economics also suggest that the material 10 should be available
in quantity and at relatively low cost.
In preference to shredded paper, grass, wood chips, shavings and
saw dust, the present mixtures 8 use agricultural crops as the base
ingredient 10. For example, whole or coarse ground grains and pulse
crops (e.g. durum wheat, hard red spring wheat, corn, barley, rice,
sunflower and beans) are particularly preferred. Shredded or chopped
and dried agriculture scraps, culls, or by-products (e.g. peanut
shells, orange peelings, corn cob, alfalfa, flax and other grasses,
husks and hulls, and recycled paper) may also be used. The foregoing
materials may be used alone or in mixtures.
In a presently preferred litter mixture, the base material 10 comprises
whole or cracked durum wheat, hard red spring wheat or corn. The
base material 10 is sifted or separated to a particulate size in
the range of 8 to 80 mesh. The base material 10 may include additives
to prevent mold, kill bugs and generally treat the base 10 for other
undesired attributes or organisms that might be occur in the base
material 10. As desired, flea and tick killers may be added to the
litter 8 to remove any contaminants that exist in the immediate
surroundings of the litter box 4. The foregoing decontaminant materials
may be added by the pet owner.
Mixed with the base material 10 is an additive or active hydrating
composition 12. The additive 12 principally consists of a quantity
of a gluten based media 14. Quantities of sodium bicarbonate or
baking soda 16 and/or a neutralizer, deodorizer or attractant scent
18 can be added as desired.
A preferred gluten based media 14 comprises a wheat derivative.
The gluten media 14 is sized to exhibit a particulate size and granular
consistency that permits ready mixing with the base material 10
and also provides an aesthetically pleasing coloration, such as
middlings of hard wheat, is preferred. Ideally, the gluten based
media 14 should have a consistency to remain in suspension in the
base material 10. For a base material 10 having a particulate size
in the range of an 8 to 80 mesh (per grain processor industry standards),
the gluten media 14 is processed to a size in a nominal range of
a 20-80 mesh.
A preferred gluten media 14 is a hard wheat derivative (e.g. durum
wheat), which is commonly used to make pasta, and which is sold
under the common name of semolina. Semolina is more grainy than
wheat flours and at the above mesh sizes tends to remain in suspension
in the base particulate 10. An intermediate ground wheat or other
gluten containing grain may also be used.
Although grains ground to a flour consistency provide desirable
hydrophilic and adhesive or hydrating properties, they do not readily
mix with the base material 10 and tend to settle to the bottom of
the container 4. A flour ground grain can also contain bugs and
become moldy over time, unless appropriate additives, discussed
above, are included or added to the mixture 8.
By maintaining a homogeneous suspension of the gluten based media
14 within the base material 10 a faster acting hydration or coalescence
is achieved with the animal waste matter. This action also prevents
the liquid from seeping to the bottom of the container 4 where
clumping and/or hardening to the container bottom can make it difficult
to clean the container 4. Tests have shown relative concentration
ratios in the range of 1 to 6 parts of base material 10 to 1 part
semolina provide acceptable clumping at the litter 8. A 1:2 ratio
or intermediate ratios provide faster clumping actions, but at greater
cost.
A quantity of sodium bicarbonate or baking soda 16 may be added
to the hydrating composition 12 to neutralize odors from the waste
matter. A relative mixture range of sodium bicarbonate to semolina
14 might comprise 1% to 5% sodium bicarbonate to semolina. Settling
of the ground bicarbonate is prevented by the semolina, which fills
voids between the particles of base material 10.
The hydrating composition 12 may also include a quantity of fragrance.
Fragrances preferably either neutralize any odors or provide a masking
scent. If used, a corn cob carrier, such as ground corn cob pieces
18 can be impregnated with a biodegradable, digestible neutralizer
or deodorizer. Presently, the corn cob pieces 18 are soaked in a
liquid material sold under the trade name NILOSORB, which includes
a desired fragrance oil. The NILOSORB is a water activated material
which upon exposure to waste liquids, releases the bound fragrance
to mask the waste odors.
The NILOSORB also has an inherent fragrance which acts like a "cat
nip" or attractant and to which test animals have shown a definite
preference. It is believed the cats are attracted to an amyl acetate
oil base of the NILOSORB. Still other oils derived from mint plants
can be added to the basic deodorizer or neutralizer 18. The deodorizer
18 is mixed with the semolina 14 at a concentration in the range
of 1% to 5% impregnated corn cob to semolina 14.
The attractant qualities of the NILOSORB deodorizer also reduces
the likelihood of rejection of the litter 8. In test cases, cats
have shown a defined preference to litters improved with the active
hydrating composition 12.
The active hydrating composition 12 is preferably pre-mixed with
the biodegradable base materials 10 discussed above. Less advantageously,
the composition 12 can be mixed with a clay base 10. The composition
12 can also be added to other commercially available cat litters,
whether or not of a scoopable variety and regardless of the base
material, to provide an improved clumping action. The latter flexibility
allows a pet owner to obtain an improved clumping litter, with less
likelihood the cat will reject the litter.
The desired clumping action of the litter 8 is principally obtained
from the gluten containing semolina 14. Within a liquid permeable
grain base or a liquid impermeable clay base, the semolina 14 demonstrates
a hydrophilic action to the liquid waste matter, which dominates
over any absorption that occurs at the base 10 or any deodorant
impregnated carrier. A liquid permeable base 14 desirably slows
the migration of the waste liquids through the litter 8 and provides
time for the liquids to react with the semolina 14. At the above
relative concentration ratios of semolina 14 to base 10 clumping
typically occurs within the first 1/2 to 1 inch of the litter 8.
Depending upon the type of base material 10 the relative rate
of liquid migration through the litter 8 and absorption by the base
10 may vary, with the base 10 absorbing greater or lesser amounts
of liquid. However, over time, the retained liquid is leached away
by the semolina 14 even if initially, partially absorbed by the
base material 10. Depending upon the amount of base material 10
encapsulated into the clumps 6 the quantity of litter 8 at the
container 4 can be adjusted with each cleaning.
Depending also upon the cost and availability of the base ingredient
10 differing types of base materials 10 may be mixed. The relative
concentrations of any base material mixture 10 should be adjusted
to provide the above describe desired moisture retention and encapsulation.
Although numerous base ingredients 10 have been suggested, it is
to be appreciated many other materials can be substituted. The type
of material may vary in relation to the locale where the litter
8 is prepared.
For a typical litter mixture 8 the gluten based composition 12
is added to the base 10 in a ratio of 30%-40% gluten composition
12 to 60%-70% by weight base 10. Presently preferred litters 8 contain
on the order of 30%-40% by weight semolina to 60%-70% by weight
ground wheat. The gluten composition 12 may be added in comparable
concentrations to commercially available litters 8.
Upon exposure to liquids, the litter mixture 8 and commercial litters
improved with the additive composition 12 have been shown to produce
rock-hard clumps 6. For example, after approximately thirty minutes
of exposure to liquid wastes, the clumps 6 can be broken only with
great difficulty and especially not from subsequent use of the litter
container 4 by the pet 2. Moreover, the clumps 6 encapsulate the
waste matter, such that any parasites contained within the waste
matter are less likely to be spread through the litter container
4 and distributed to other pets which may use the container 4.
A further improvement to the litter mixture 8 or additive composition
mixture 12 is to apply a wetting additive or dust inhibitor 20 to
the mixtures. For a litter 8 the inhibitor 20 is applied during
the blending of the base 10 gluten media 14 and other desired additives,
such as sodium bicarbonate 16 and/or the deodorizer 18. For an additive
mixture 12 the inhibitor 20 is applied the same, although at concentration
ratios near the lower end of the mentioned ranges, due to typically
reduced concentrations of fines. Preferably, the inhibitor 20 should
not initiate hydration of the gluten ingredient and only promote
dust adhesion.
The dust inhibitor 20 is provided to remove dust or fines (i.e.
particles smaller than 80 mesh) which pass through the sifting equipment
that sizes the base 10 and gluten media 14. During mixing and packaging,
the dust may be controlled with conventional dust collection and
air handling equipment. However, steps have not previously been
taken to reduce or control the dust at the packaged litter 8. A
substantial portion of the dust is therefore retained in the packaged
litter 8. Consequently, each time the litter 8 is dispensed or agitated,
the dust is released to the pet owner's home.
The problem has been alleviated in the present invention with the
addition of small quantities of inhibitor 20 which comprise a wetting
additive. Exemplary additives are water soluble, anionic, nonionic,
amphoteric or synthetic surfactants, surfactant mixtures, or fatty
acid based soaps or synthetic detergents. The surfactant molecules
provide hydrophobic sites which bond or agglomerate the dust and
mixture particulates to each other. Free hydrophilic sites are available
to attract moisture present in the animal waste admitted to the
litter 8 and promote hydration at the gluten media 14.
With attention to FIGS. 3 and 4 and particularly FIG. 4 the inhibitor
20 is admixed with the litter ingredients to coat the individual
particles as they are blended at a mixing station. The base 10 and
gluten based composition 12 are admitted to a blender 30 and are
initially blended at a ribbon auger 32. A controlled gating assembly
34 admits the initially blended base 10 and gluten based composition
12 to a conveyor auger 36 which directs the mixture to a coating
chamber 38 having a paddle auger 40.
The inhibitor 20 is injected into the coating chamber 38 via a
pressure pump 41 having a gating valve and a conduit 43. Alternatively,
a suitable number of spray orifices (not shown) might be provided
with another atomizing dispenser. The volume of inhibitor 20 is
controlled to evenly coat the particulates and the contained fines.
The inhibitor 20 is admitted to the chamber 38 as a foam, where
the foam mixes and coalesces with the fines to trap and agglomerate
the fines to the larger particulates in the litter 8 and maintain
the granular consistency of the litter 8. The auger 40 blends the
coated ingredients to facilitate bonding between the fines and larger
particulates.
The speed of the augers 32 36 and 38 are controlled to provide
uniform coating and optimal agglomeration of the dust. Once the
litter mixture 8 is dispensed at the outlet 44 an essentially dust
free litter mixture 8 is obtained. A gluten based composition 12
used as an additive for commercial litters would be similarly mixed
with the inhibitor 20 although at reduced concentrations of inhibitor
20.
Minimal hydration occurs at the gluten media due to the low moisture
content of the inhibitor. However, as necessary, the litter 8 can
be air dried or heated to an appropriate temperature (e.g. 100-300
degrees Fahrenheit) for a sufficient duration to remove any residual
moisture from the inhibitor 20. At the present concentrations of
inhibitor 20 heating has not proven necessary.
Presently preferred inhibitors 20 are a water diluted surfactant
solution or a diluted liquid soap or synthetic detergent, which
are preferred over oil based additives. Oil based additives tend
to repel the liquid animal wastes and produce less efficient dispersal
and absorption of the liquid waste. An alcohol dilutant might also
be used.
The water content of the inhibitor 20 relative to the base 10 and
hydration composition 12 is maintained to a relatively low concentration
to prevent any reduction in the absorbancy of the litter 8 through
premature hydration of the gluten media 14. The inhibitor 20 is
also sparingly applied to the litter ingredients in the blending
operation to prevent caking or stratification of the ingredients
and maintain the desired granular consistency of the litter mixture
8.
A presently preferred inhibitor 20 is a 0.1% to 20% solution by
weight of an anionic, nonionic, amphoteric or synthetic surfactant
to water. The inhibitor is applied at a concentration in the range
of 1/2 oz. to 7 oz. per 10 lbs of litter mixture 8 containing 2%
to 10% fines. More typically, 3 to 5 oz. are used when an unfiltered
or unwashed base 10 is used. The inhibitor concentration can be
determined from FIG. 3. The inhibitor 20 exhibits a viscosity in
the range of 10 to 50 SAE.
Exemplary anionic surfactants are lauryl polyglucose, sodium laureth
sulfate, TEA lauryl sulfate and sodium lauryl sulfate. Exemplary
nonionic surfactants are a nonoxynol (1-10). Various amphoteric
or synthetic surfactants known to those skilled in the art may also
be used, although are more costly.
Another inhibitor 20 that has been used to advantage is liquid
soap, such as found in a variety of dish soaps and shampoos. For
example, dilute concentrations of brand name soaps, such as IVORY
dish soap and SUAVE shampoo, have been admixed with the litter 8.
As necessary, the soap additive 20 is also diluted with small quantities
of water or alcohol to a viscosity on the order of 10 to 50 SAE.
The viscosity is determined to be compatible with the pressure pump
41.
The deodorizer and/or attractant 18 may also be injected into the
litter 8 with the inhibitor 20 in lieu of being impregnated in a
carrier, such as corn cob. In this instance, a suitable nonionic
surfactant is included at the inhibitor 20 to promote mixing of
the deodorizer 18. As necessary other additives may be included
to promote a stable inhibitor 20. The foregoing deodorizers or a
variety of other known deodorizers can be used to advantage. The
deodorizer 18 may also be separately injected, although at present
the deodorizer 18 is mixed and applied with the inhibitor 20.
The quantity of inhibitor 20 required is proportionately varied
in relation to the amount or percentage by weight of fines present
in the litter mixture 8. FIG. 3 depicts a graph from which particular
concentrations of inhibitor 20 (i.e. surfactant or soap) to percentage
fines can be determined. For example, for ten pounds of a litter
8 having approximately 5% fines by weight, one ounce of soap would
be applied to contain the fines. As the percentage of fines increases,
an appropriate, increased quantity of inhibitor 20 can be interpolated
and applied.
Greater amounts of fines have been noted in litters 8 having a
clay base material versus organic agricultural base materials, such
as ground or cracked wheat. Consequently, correspondingly greater
concentrations of inhibitor 20 are required when using a clay base
10 or material that is not pre or post cleaned. The concentration
of fines can be reduced by washing or filtering the base materials
as appropriate.
It is also to be appreciated the inhibitor 20 can be added to any
type of available commercial litter. The inhibitor can also be added
to a variety of non-food mixtures containing concentrations of problematic
dust for a variety of applications.
The invention has been described with respect to various preferred
biodegradable cat litter and litter additive mixtures which include
a base material of organic agricultural materials and a gluten based
additive composition including wheat middlings. The ingredients
may be mixed to various combinations and concentrations and the
litter mixtures may include other ingredients to facilitate pet
use and promote useable life, storage life and clean-up. The base
and gluten based material may also comprise the same material ground
to different mesh sizes.
Various modifications and improvements thereto have also been suggested.
It is to be appreciated, however, that still other equivalent compositions
and mixtures may suggest themselves to those skilled in the art.
The invention should therefore be interpreted to include all those
equivalent compositions within the spirit and scope of the following
claims. |