Note: Descriptions are shown in the official language in which they were submitted.
1~5~
BACKGROU~D OF THE INVENTION
1. Field of the Invention
This invention relates to the control of fleas and
ticks on warm-blooded animals, such as cats and dogs, by
application of a combination insecticidal gas and powder
generator device. More particularly, this invention relates
to novel compositions and to methods of manufacture of a pet
collar comprised of a synthetic resin such as polyvlnyl chloride
(PVC) having dispersed therein the insecticide dimethyl 1,2-
dibromo-2,2-dichloroethyl phosphate, commonly known as naled,
and a substantially non-volatile carbamate.
2. Discussion of the Prior Art
Heretofore, phosphate insecticides such as dimethyl
2,2-dichlorovinyl phosphate commonly known as dichlorvos (DDVP)
or by its trademark Vapona, or dimethyl 1,2-dibromo-2,2-dichloro-
ethyl phosphate commonly known as naled, have been widely used
for controlling insects. The incorporation of naled and a
surface porosity control component in a solid thermoplastic
resinous pet collar to control fleas is disclosed in U. S. Patent
3,918,407. The incorporation of 3 to 25~ of a substantially
non-volatile carbamate in a solid thermoplastic vinylic resin in
the form of an animal collar is disclosed in U. S. Patent
3,852,416. German Auslegeschrift 1,128,219 alleges that phosphoric
acid esters which are ineffective as insecticides when used at
standard concentrations, when combined with carbamates, greatly
intensify synergetically their effectiveness as insecticides or
acaricides. United States Patent 3,111,539 discloses various
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~C~5~44
carbamates as being useful insecticides.
SUM~ RY OF THE INVENT ION
This invention provides resinous compositions in the form
of an animal collar which releases naled insecticide and a
substantially non-volatile carbamate insecticide over an
extended period of up to 120 days to control fleas and ticks
on the animal wearing the collar. The cured resinous
compositions from which collars are prepared contain initially
dissolved or suspended in the interstices thereof from about 5 to
about 20 weight % naled and from about 2 to about 12 weight
substantially non-volatile carbamate insecticide.
The present invention is based on the discovery that when
naled insecticideJ a substantially non-volatile carbamate
insecticide and a surface porosity control component are incor-
porated in a resin matrix the naled insecticide is released from
the cured collar at a greater rate than from a cured collar
containing only naled, thereby resulting in a more effective
collar for the control of fleas and tick~ on warm-blooded animals,
particularly dogs and cats. The invention is also based on the
discovery that naled is emitted from the collar as a vapor and
the carbamate migrates from the collar as a powder without
affecting the release of each other. Moreover, the carbamate
which migrates as a powder onto the surface of the collar is
substantially dry and free of liquid naled.
Cured resinous compositions for cats will contain 5 to 12
weight % naled and 2 to 5 weight % carbamate, preferably 7 to 10
weight ~ naled and 2 to 3.5 weight % carbamate. cured resinous
_ ~
` ~ ~57144
compositions for dogs will contain 8 to 20 weight % naled and 2 to 12 weight
% carbamate, preferably 12 to 17 weight % naled and 3.5 to 8 weight %
carbamate.
In summary therefore this invention provides a flea and tick
control collar for a warm-blooded animal comprising: a strip of flexible
synthetic resin material containing between about 5 to 20 weight % naled
and about 2 to about 12 weight % of a substantially non-volatile carbamate
insecticide and having a width, thickness and length sufficient to encircle
the neck of the animal with clamping means at one end of the collar for
engaging a spaced collar portion to prevent loss of the collar from the
neck of the wearing animal; said strip being formed from a dispersion of a
synthetic resin, naled, a substantially non-volatile carbamate and a surface
porosity control component that is non-reactive in the dispersion and has
a boiling point at or below the curing temperature of said resin, said
dispersion being heated to its curing temperature to produce surface openings
in communication with pores in said strip by vaporization of said porosity
control component to provide for release of naled gas and said carbamate
at a rate effective to control fleas and ticks on said animal throughout
a period of at least about ~0 days.
It also provides a method of treating a warm-blooded animal for
ticks and fleas which comprises: providing a strip having a width and
thickness and length suitable for use as a collar for said animal, said strip
comprising a mixture of a synthetic resin and from between 5 to 20 weight ~
naled and from about 2 to about 12 weight % of a substantially non-volatile
carbamate insecticide; said strip being formed from a dispersion of said
synthetic resin, naled and said substantially non-volatile carbamate,
and a minor amount of a surface porosity control agent that is non-reactive
in the dispersion and has a boiling point at or below the curing temperature
of said dispersion is formed into said strip at the curing temperature to
vaporize said control agent and produce surface porosity in said strip to
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~1~57144
provide for release of naled as vapor and said carbamate as powder at a
rate to effectively control ticks and fleas on said animal throughout a
period of at least about 90 days but insufficient to be toxic to said
animal; providing on said collar near one end a clamping means for engaging
a spaced collar portion to prevent loss of the collar from the neck of the
wearing animal; and placing and maintaining said collar on said animal.
The invention thus provides an insect combatting device in the
form of a solid composition to be worn as an animal collar which releases
naled insecticide and a carbamate insecticide over an extended period of
time for effective control of fleas and ticks.
According to the method of this invention there is provided a
method of treating animals by making a strip of synthetic resin containing
from about 5 to about 20 weight % naled insecticide and from about 2 to
about 12 weight % of a substantially non-volatile carbamate through the
use of a volatile additive which is released during the curing step to
produce a texture including porous surface openings which allow for an
unexpectedly large increase in the release of naled gas at a rate effective
to control fleas and ticks for a period of up to about 120 days.
These and other aspects of the invention will become re fully
apparent from the claims, and from the description as it proceeds in
connectîon with the appended drawings wherein:
FIG~ 1 is a plan view of a representative pet collar embodying
the present invention;
FIGo 2 is a view of the collar in cross section taken along
lines 2-2 of FIG~ 1;
FIG 3 is a graph showing the comparative rate of naled release
in collars employing naled and SendramTM ~2-isopropoxyphenyl-N-methyl
carbamate) with a surface porosity control component or additive in
accordance with the present invention,
57~
naled with a surface porosity control component or additive
and naled without ~he additive.
Referring now to the drawings, FIGS. 1 and 2 show a typical
collar adapted for pets such as dogs or cats. The components
making up a satisfactory naled carbamate-containing pet collar
include a synthetic resin that is sufficiently pliable or
flexible to be encircled around the animal's neck and has a
strength sufficient to remain on the animal throughout a period
of at least 4-1/2 months or the period during which naled
carbamate is released in amounts effective to control fleas.
The collar constituted a band or strip of a PVC-naled-
carbamate combina~ion with the concentration of PVC sufficiently
large to give the collar physical properties such as strength,
flexibility, and freedom from tackiness to make it suitable for
use as a collar for the animal. Normally, the cross-sectional
dimensions of the collar vary from about one-fourth to five-
eighth inch in width, and from about three thirty-seconds to
three-sixteenths inch in thickness For collars o~ the present
invention employing the PVC-naled-carbamate combination, the
preferred dimensions are three-eighth in width and one-eighth
inch in thickness, and the cross section is as illustrated in
FIG~ 2.
The collars are made of sufficient length to encircle the
neck of the largest dog or cat to be encountered, and for smaller
animals, the end of the collar may be cut off to reduce the size
of the collar to correspond with the size of the animal. With
the PVC-naled-carbamate combination and dimensions as given
~5~44
above, the perimeter of the collar is about one inch and the
mass of the collar is about one gram per lineal inch. By use
of a clasp having a friction grip~ the collar can be adjustably
placed on the animal without the need for holes.
DETAILED DESCRIPTION AND PREFERRED EMBODIMENTS
In accordance with the present invention naled insecticide,
a substantially non-volatile carbamate insecticide and a surface
porosity control component are incorporated into resin compo-
sitions prior to curing. The cured collars release vaporized
0 naled insecticide and powdery carbamate insecticide over an
extended period of time for control of fleas and ticks on animals.
The collar is comprised of a strip of flexible synthetic resin
material containing from about 5 to about 20 weight ~ naled
insecticide and from about 2 to about 12 weight ~ of a substan-
tially non-volatile carbamate insecticide and having a width,
thickness and length sufficient to encircle the neck of the
animal with clamping means at one end of the collar for engaging
a spaced collar portion to prevent loss of the collar from the
neck of the wearing animal.
The strip is formed from plastisol dispersions or dry blend
mixtures of a synthetic resin, naled insecticide, carbamate
insecticide and a surface porosity control component. Plastisol
dispersions may be cured by heating in open faced molds and dry
blend mixtures may be extruded with heating to curing temperatures
to provide strips of flexible plastic. The compositions are
characterized by their provision of the benefits of naled
insecticide and a substantially non-volatile carbamate insecticide
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1057144
for control of fleas and ticXs on animals. The naled penetrates
the atmosphere surrounding the animal as a vapor and the
carbamate as it migrates onto the collar surface as a powder is
displaced therefrom by rubbing or dusting onto the hair o~ the
animal. The compositions serve as a reservoir providing
continuous replenishment of naled insecticide and carbamate
insecticide.
The carbamates which can be used in combination with naled
in the present invention are represented by the formula:
R-0-C-N~
\R2
Formula I
wherein;
R is phenyl, substituted phenyl, naphthyl, substituted
naphthyl, heterocyclic or substituted heterocyclic,
R is hydrogen or lower alkyl, and
R2 is lower alkyl.
l~he term "lower alkyl" as used herein refers to an alkyl
radical having one to six carbon atoms. The carbon chains can
be straight or branched. The term "lower alkoxy" has the
formula -0-lower alkyl. The substituted phenyl radical or the
substituted naphthyl radical can have one or more sùbstituents
selected from radicals such as lower alkyl, chloro, bromo,
fluoro, lower alkoxy, lower alkylamino, lower dialkylamino or
lower alkylthio. The preferred number of substituents is one
to two. The term "heterocyclic" as used herein refers to a
-- 7 --
~057~44
heterocyclic group having an oxygen atom, a sulfur atom or one
or two nitrogen atoms in the nucleus thereof. The term
Dsubstituted heterocyclic" as used herein refers to a hetero-
cyclic group substituted with one or more groups such as lower
alkyl, lower alkoxy, lower alkylthio, lower alkylami.no, lower
dialkylamino, carbamoyl, alkyl substituted carbamoyl or halogen.
he preferred number of substituents is one to two.
Carbamates which can be used in practicing the present
invention include:
2-isopropylphenyl-N-methyl carbamate,
2- isopropoxyphenyl-N-methyl carbamate,
3-(1-methylbutyl)phenyl-N-methyl carbamate,
3-(1-ethylpropyl)phenyl-N-methyl carbamate,
6-chloro-3,4-xylenyl-N-methyl carbamate,
4-methylthio-3,5-xylenyl-N-methyl carbamate,
N-methyl-l-naphthylcarbamate,
N-ethyl-l-naphthylcarbamate,
N-isopropyl-l-naphthylcarbamate,
N-butyl-l-naphthylcarbamate,
N-hexyl-1-naphthylcarbamate,
1-(4-chloronaphthyl)-N-methyl carbamate,
1-(5,6-dihydronaphthyl)-N-methyl carbamate,
1-(5,8-dihydronaphthyl)-N-methyl carbamate,
4-benzothienyl-N-methyl carbamate,
1-phenyl-3-methylpyrazol-5-yl-N,N-dimethyl carbamate,
2-(N,N-dimethylcarbamyl)-3-methylpyrazol-5-yl-N,N-
dimethyl carbamate,
~C~57144
3,4-xylyl-~-methylcarbamate,
3-methyl-5-isopropyl-N-methylcarbamate,
2-chlorophenyl-N-methylcarbamate, and
` 2,2-dimethyl-1,3-benzodioxol-4-yl-N-methylcarbamate.
The preferred carbamates are 2-isopro~yphenyl-N-methyl-
; carbamate, commonly known as propoxur or SendranTM and N-methyl-l-naphthylcarbamate, commonly known as carbaryl or SevinT .
The carbamates of Formula I and methods for their preparation
have been described in U. S. Patents 2,903,478; 3,111,539 and
3J203J853-
In the preparation of the plasticized thermoplastic
component of the present invention, there can be employed any
suitable thermoplastic resin which is satisfactorily compatible
with the plasticizer employed, naled and the carbamates. The
various known synthetic resins which can be used for a pet
collar containing the combination of insecticides of this
invention include materials such as polyethylene, polypropylene,
copolymers of ethylene and propylene, nylon, cellophane, poly-
acrylates such as polymers and copolymers of methylacrylate,
ethylacrylate, methylmethacrylate and ethylmethacrylate,
polymers of vinyl compounds such as polystyrene, polymerized
divinylbenzene, polyvinylhalogenides, such as polyvinylchloride;
polyvinylacetals, such as polyvinylbutyral; polyvinylldene
compounds such as polyvinylidenechloride, polyvinylacetate,
ethylvinylacetate-vinylacetate copolymers; copolymers of vinyl-
chloride and vinylacetate, polyurethanes, polyaldehydes, and
thermoplastics.
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~057144
Polyvinyichloride (PVC) homopolymers and copolymers with
other polymers such as polyvinyl acetate (PVA) are preferred
synthetic resin materials. Suitable PVC resins are commercially
~ available and include, for example~ PVC homopolymer dispersion
resin Firestone FPC-6337 available from Firestone Plastics Co.
and PVC homopolymer extender resin Borden 260S available from
the Borden Co. and mixtures thereof. Other suitable, commercially
available PVC resins are known in the art. Suitable PVC-PVA
copolymers are also commercially available and include, for
example, Geon 135 (Goodrich Corp.)~ PVC-74 (Diamond Alkali Co.)
and XR-6333 (Exxon-Firestone). Other PVC-PVA copolymers are
also known in the art.
The preparation of synthetic resin-insecticide combinations
is achieved by conventional methods. Because of the compatibility
f naled and the carbamates in the resin dispersions, the
compositions may be prepared merely by mechanically mixing of
the insecticides with powdered resin. Fluid pastes, or plastisol
dispersions, can be made which/ as is known, can be molded,
extruded, cast, or otherwise formed into the shape o~ a band or
strip. Where the prepolymerized resin exists in liquid formJ
as in the case of such monomers as styrene or methyl methacrylate,
the insecticides may be incorporated in the liquid before it is
polymerized or cured. The term "dispersion" as used herein is
intended to include mixtures of a solid with a liquid, a liquid
with a liquid and a solid with a solid.
In the embodiments where polyvinyl resins are used~
plasticizers and other additives commonly used for providing
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~57144
the flexibility, strength and surface characteristics desired
for a pet collar are well known to those skilled in this art,
and no further discussion is deemed necessary here. In addition,
coloring and odor control agents may be employed in the collars
of the present invention to enhance consumer acceptance.
Plasticizers suitable for preparing the plasticized thermo-
plastic resin component of the compositions of the present
invention are those conventionally employed in plasticizing
solid thermoplastic resins. The particular plasticizer or
0 plasticizers employed will depend upon the resin and its
compatability therewith. Suitable plasticizers include esters
of phosphoric acid such as tricresyl phosphate and esters of
phthalic acid such as dioctyl phthalate. Other esters such as
those of adipic acid, azalaic acid, maleic acid, ricinoleic
acid, myristic acid, and trimellitic acid as well as complex
linear polyesters, polymeric plasticizers and epoxidized soybean
oils.
Other ingredients such as stabilizers, lubricants, fillers
and coloring materials can be included in the compositions of
0 the present invention without changing fundamental properties
thereof. Suitable stabilizers are the antioxidants and agents
which protect the resin from ultraviolet radiation,undue
degradation during processing such as casting and extrusion, a
wide variety of which are commercially available.
Some stabilizers such as epoxidized soybean oils or
epoxidized octyl tallate serve also as a secondary plasticizer.
Stearates including stearic acid and low molecular weight
1~571~4
polyethylene are examples of lubricants which can be used.
Because of the low vapor pressure of naled, which is
believed responsible for a relatively low release rate, the
naled release rate from PVC-naled-carbamate collars is enhanced
by the use of an additive in the dispersion. This makes possible
effective flea control at lower initial naled concentrations
and a collar having an increased effective life.
The additive, also referred to as a surface porosity
control component, is present in the final plastisol dispersion
or mix used in forming the collar, and hence must be non-reactive
with the other components of the dispersion or mix. The main
function of the additive is to provide a surface porosity which
preferably includes pores extending part way into the body of
the collar. The desired surface characteristics are obtained
by the vaporization of the additive during the curing period.
Hence the additive should comprise one or more compounds having
a boiling point at or below the curing temperature Or the resin.
Compounds which are suitable as the surface porosity
control component in PVC resins which are cured at a temperature
in the range of between about 300 to 375 F. include aldehydes
and their lower alkyl acetals containing bromine or chlorine.
The porosity control component may thus include one or more of
the following which have approximate boiling point temperature
as set forth:
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1~57144
Name B.P. F.
chloroacetaldehyde 185
dichloroacetaldehyde 192
chloral 218
bromoacetaldehyde 176-221
dibromoacetaldehyde 288
bromal 346
bromodichloroacetaldehyde 258
chlorodibromoacetaldehyde 299
bromochloroacetaldehyde 233
2-bromopropanol 229
The surface porosity control component is included in the
synthetic resin-naled-carbamate combination in an amount
sufficient to produce surface porosity by its vaporization during
curing of the dispersion whereby said cured strip releases naled
gas at a rate effective to control fleas throughout a period of
at least about 90 days without forming droplets on the strip.
While the amount of the porosity control component to be used
depends on the density of surface openings desired and somewhat
on the particular procedure used for curing the resin, it is
generally from about o.8 to 4, preferably from about 1 to 3 wt.
percent of the dispersion.
The invention is illustrated by the following Examples
which are to be considered as illustrative of the present
invention. It should be understood, however, that the invention
is not limited to the specific details of the Examples.
1~57144
Example 1
A mixture in parts by weight of
35.82 PVC homopolymer dispersion Resin Type A
(Firestone FPC-6337TM)
17.32 PVC homopolymer extender Resin Type B
(Borden 260STM)
16.36 di-2-ethylhexylphthalate
2.36 epoxidized octyl tallate
0.94 calcium and zinc stearate powders
19.90 naled (dimethyl 1,2-dibromo-2J2-dichloroethyl
phosphate
2.30 surface porosity control component
(e.g. bromodichloroethylphosphate)
5.00 2-isopropoxyphenyl N-methylcarbamate
(goO and amorphous silica (loO in
dust form
10~ ~ ~
\
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57144
was thoroughly triturated to form a plastisol. A portion of
the plastisol was metered to a machined aluminum open-faced
cast mold having a cavity 3/8" in width x 21'' in length x 1/8"
in depth. Temperature of the mold at filling time was approxi-
mately 200F. The mold was immediately placed in an oven and
heated to 310-335 F. by means of hot air and radiant heat. The
mold containing the dispersion was moved through the oven over a
6 minute period. Thus, the dispersion was maintained at or
above the curing temperature of 310-335 F. for about 6 minutes.
Cooling was then started, the temperature being lowered rapidly
to 305 F. within 30 seconds. The cured strip was immediately
thereafter removed from the mold and cooled rapidly to room
temperature. The top side of the collar was rounded due to the
meniscus formed on filling the moldJ the shape being retained
during curing.
Analysis of the collar after curing and cooling showed the
naled (dimethyl 1,2-dibromo-2,2-dichloroethyl phosphate) content
of the collar to be 17.9 weight 5~ and the 2-isopropoxyphenyl-
N-methyl carbarnate content to be 4.4 weight ~.
Example 2
A mixture in parts by weight of
34.19 PVC homopolymer dispersion Resin Type A
(Firestone FPC-6337 M)
16.54 PVC homopolymer extender Resin Type B
(Borden 260STM)
15.62 di-2-ethylhexylphthalate
2.25 epoxidized octyl tallate
0.90 calcium and zinc stearate powders
(50 - 50 by wt.)
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1057~44
19.90 naled (dimethyl 1,2-dibromo-2,2-dichloroethyl
phosphate)
2.30 surface porosity control component (e.g. bromo-
dichloroacetaldehyde)
8.30 2-isopropoxyphenyl N-methylcarbamate (90%)
and amorphous silica (loO in dust form
100.00 total
was thoroughly triturated to form a plastisol. A portion of the
plastisol was molded into a collar 3/8" x 21" x 1/8" thickness
as in Example 1. Analyses of the collar after curing and
cooling showed the content of dimethyl 1,2-dibromo-2,2-dichloro-
ethyl phosphate to be 18.3 weight % and the 2-isopropoxyphenyl
~-methyl carbamate content to be 7.4 weight ~.
Example 3
A mixture in parts by weight of
37.00 PVC homopolymer disTPersion Resin Type A
(Firestone FPC-6337 M)
17.90 PVC homopolymeTMextender Resin Type B
(Diamond 7-44L
17.58 di-2-ethylhexylphthalate
2.44 epoxidized octyl tallate
o.98 calcium and zinc stearate powders
(50 - 50 by wt.)
17.55 naled (dimethyl 1,2-dibromo-2~2-dichloroethyl phosphate)
1.95 surface porosity control component
4.60 N-methyl-l-naphthylcarbamate
100.00 total
was thoroughly triturated to form a plastisol. A portion of
the plastisol was molded into a collar 3/8" x 21" x 1/8" thick-
neCs as in Example 1. Analysis of the collar after curing and
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r 1~ 57~L 4 4
cooling showed the content of dimethyl 1,2-dibromo-2,2-dichloro-
ethyl phosphate to be 15.0 weight % and the content of l-naphthyl-
N-methyl carbamate to be 4.2 weight ~.
COMPAR~TIVE EX~MPLE 1
Following the procedure of Example 1 and using a plastisol
dispersion consisting in parts by weight of
35.62 PVC homopolymer disTPersion Resin Type A
(Firestone FPC-6337 M) (a)
17.23 PVC homopolymer extender Resin Type B
(Borden 260STM) (b)
16.27 di-2-ethylhexylphthalate (DOP)
2.34 epoxidized octyl tallate (EPO)
0.94 calcium and zinc stearate powders
(50 - 50 by wt.)
27.60 naled (dimethyl 1,2-dibromo-2,2-dichloroethyl
phosphate)
100.00 total
was thoroughly triturated to form a plastisol. A portion of the
plastisol was molded into a collar 3/8" x 21" x 1/8" thickness.
Analysis of the collar after curing and cooling showed the
content of dimethyl 1,2-dibromo-2,2-dichloroethyl phosphate to
be 22 weight ~.
COMPARATIVE EXAMPLE 2
Following the procedure of Example 1, a mixture in parts
by weight of
38.3 PVC homopolymer dispersion Resin Type A
(Firestone FPC-6337
18.5 PVC homopolymer extender Resin Type B
(Diamond PVC-7-44L
18.7 di-2-ethylhexylphthalate
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1~57144
2.5 epoxidized octyl tallate
1.0 calcium and zinc stearate powders
(50 - 50 by wt.)
21.0 naled (dimethyl lJ2-dibromo-2J2-dichloroethyl phosphate)
100.0 total
was thoroughly triturated to form a plastisol. A portion of
the plastisol was molded into a collar 3/8" x 21" x 1/8" thick-
ness as in Example 1. Analysis of the collar after curing and
cooling showed the content of dimethyl 1,2-dibromo-2,2-dichloro-
ethyl phosphate to be 16 weight ~.
Example 4
A mixture in parts by weight of
36.05 PVC homopolymer dispersion Resin Type A
(Firestone FPC-6337 M)
17.44 PVC homopolymer éxtender Resin Type B
( Borden 26oSTM)
16.88 di-2-ethylhexylphthalate
2.36 epoxidized octyl tallate
o.88 calcium and zinc stearate powders
(50 - 50 by weight)
19.25 naled (dimethyl 1,2-dibromo-2,2-dichloroethyl
phosphate
2.14 surface poro~ity control component (e.g. J bromo-
dichloroacetaldehyde)
5.00 2-isopropoxyphenyl-N-methyl carbamate 90%
and amorphous silica lO
100.00 total
was thoroughly tritura1:ed to form a plastisol. A portion of the
plastisol was molded into a collar 3/8" x 21" x l/ô" thickness
as in Example 1. Analysis of the collar after molding and
-- 18 --
~57~44
curing showed the dimethyl 1,2-dibromo-2,2-dichloroethyl
phosphate content to be 16.2 weight ~ and the 2-isopropoxyphenyl-
N-methyl carbamate content to be 4.2 weight ~.
Example 5
A mixture in parts by weight of
42.33 PVC homopolymer dispersion Resin Type A
(Firestone FPC 6337 M)
20.47 PVC homopolymer extender Resin Type B
(Borden 260STM)
19.81 di-2-ethylhexylphthalate
2.77 epoxidized octyl tallate
1.04 calcium and zinc stearate powders (50 - 50 by weight)
9.70 naled (dimethyl 1,2-dibromo-2,2-dichloroethyl
phosphate)
1.08 surface porosity content component (e.g., dibromo-
acetaldehyde)
2.80 2-isopropoxyphenyl-N-methyl carbamate 90% and
amorphous silica 10
100.00 total
was thoroughly triturated to form a plastisol. A portion of
the plastisol was molded into a collar 3/8" x 21" x 1/8" thick-
ness as in Example 1. Analysis of the collar after moulding
and curing showed the dimethyl 1,2-dibromo-2J2-dichloroethyl
phosphate content to be 7.0 weight ~ and the 2-isopropoxyphenyl-
~-methyl carbamate content to be 2.4 weight ~.
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~1~57144
Example 6
A mixture in parts by weight of
40.73 PVC homopolymer dispersion Resin Type A
~Firestone FPC 6337 M) (a)
19.70 PVC homopolymer extender Resin Type B
(Diamond PVC-7-44LTM) ( f)
19.36 di-2-ethylhexylphthalate (DOP)
2.68 epoxidized octyl tallate (EPO) (c)
1.08 calcium and zinc stearate powders (c)
(50 - 50 by weight)
12 .75 naled (dimethyl 1,2-dibromo-2,2-dichloroethyl
phosphate)
3.70 l-naphthyl-N-methyl carbamate
(97.5% active)
100.00 total
was thoroughly triturated to form a plastisol. A portion of
the plastisol was molded into a collar 3/8" x 21" x 1/9"
thickness as in Example 1. Analysis of the collar after curing
and cooling showed the content of dimethyl 1,2-dibromo-2,2-
dichloroethyl phosphate to be 10.0 weight S~ and the content of
l-naphthyl-N-methyl carbamate to be 3.5 weight ~.
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~57~44
Insecticidal Efficac~ of Collars
The insecticidal efficacy of the animal collars of the
present invention was determined using animals confined to
cages wearing various collars. The animals were infested with
fleas or tlcks on the same day the collar was applied to the
animal and periodically thereafter. The number of surviving
fleas were counted after each infestation. control animals
wore collars containing only naled (dimethyl 1,2-dibromo-2,2-
dichloroethyl phosphate).
Three groups of dogs (6 dogs per group) were provided
0 with collars from Example 1, Example 2 and Comparative Example 1.
Each dog was infested with 50 fleas (CtenocePhalides felis)
biweekly for a total of nine infestations. Flea counts were
made at days 1~ 3 and 5 post infestation. The data in Table 1
shows a 63-66~ greater reduction in flea content on animals
wearing the collars of the present invention during the first
nineteen days of the test period. The number of fleas present
each day was counted.
The data in Table 2 shows the results of the entire test
period with a 26-57% greater reduction in flea content on
\ animals wearing the collars of the present invention. The dead
fleas were counted in the pans beneath the cage of each dog on
days 1-5 after each infestation.
1~57~4 4
Table 1
Average No. of Residual Fleas/Doq
Comparative
ExamPle 1 Example ? Example 1
O -- _
1 1.17 0.83 6.83
3 0.83 l . oo 2.17
0.33 o.o 3.17
14
1.83 3.67 3.50
7 1.83 1.17 3.50
9 l.oo 1.17 1.83
6.99 total 7.84 total 21.00 total
lDogs infested at day O and day 14.
Table 2
Average ~o. of Dead Fleas/Doq
Day Comparative
Infestation Count Example 1 Example 2 Example_l
o 1-5 l22 22.3 16.7
14 15-lg 24.3 17.7 20.2
28 29-33 22.0 20.5 ll7.o
42 43-47 19.7 9.8 14.3
56 57-61 17.0 16.2 10.7
71-75 16.5 15.2 6.2
84 85-89 16.3 16.3 11.2
98 99-103 19.2 14.5 8.5
112 113-117 ~o.o 9.~ 8.o
-
177.0 total 141.3 total 112.8 total
Estimated; pans cleaned inadvertently.
1~57~44
In another comparative test, 9 individual dogs were fitted
with collars from Example 4~ and 3 individually caged dogs were
fitted with collars from Comparative Example 2. The dogs were
infested at days o, 14 and 29 with 50 fleas per dog (Ctenocep-
halides felis). The number of residual fleas per dog was
determined on various days post infestation. The data are shown
in Table 3~
Table 3
Average No. of Residual Fleas/Dog
Comparative
Day Example 4 Example 2
O _ _
2 2~89 4.67
4 o.56 2~0
6 0~0 0~0
0~44 2~0
14
16 o.67 1.0
18 0~22 o.67
21 0~11 0~0
24 0~11 o.67
28 0~0 0-33
29
1 ~ 89 1 ~ 0
~2 1~11 2~0
loO 2~0
38 O ~ 67 1.0
42 0~ 0
9~89 Total 18~34 Total
The efficacy of the collars of the present invention were
tested on dogs infested with brown dog ticks (Rhipecephalus
sanguineus). The number of residual live ticks and the number
of live attached ticks per individual dog was determined per
post infestation days. Each dog was infested with 50 ticks at
days 0, 14 ~ 28 and 42 ~ The tick counts were made on days 1, 3
5 and 14 post infestation. The data are shown in Table 4
~ 23 ~
~057144
Table 4
No. Live Residual Ticks ~o. Live Attached Ticks
Comparative Comparative
Days Example 4 Example 2 Example 4 Example 2
0-14 43.8 63.9 33.9 47.2
16-28 36-6 59.3 24.8 47.3
30-42 28.5 43.8 22.5 36.8
44-56 33.4 27.0 23.4 6.9
142.3 194.0 94.6 138.2
....
- 24 -
~057144
SUMMARY OF ADVANTAGES
The pet collars of the present invention have the advantage
of the release of both a vaporous insecticide and a substantially
non-volatile powdery insecticide. The naled vapor releases to
the atmosphere surrounding the pet and the carbamate powder
migrates onto the surface of the collar and then onto the coat
of the animal.
The resin-naled-carbamate pet collars of the present
invention have improved naled release over pet collars containing
only naled. The net effect of increased naled release and the
migration of the carbamate onto the collar and from the collar
surface onto the coat of the animal is a more effective collar
against the infestations of fleas and ticks.
The pet collars containing the combination of naled and
carbamate provide greater protection against ticks than naled
alone, particularly on free running animals where the naled
vapor is released to unconfined space. The carbamate as a powder
is distributed on the animal coat and more effectively controls
the ticks and results in a larger percentage kill.
The present invention may be embodied in other specific
forms without departing from the spirit or essential character-
istics thereof. The presently disclosed embodiments are therefore
to be considered in all respects as illustrative and not restrictive,
the scope of the invention being indicated by the appended claims
rather than by the foregoing description, and all changes which
come within the meaning and range of equivalency of the claims
are therefore intended to be embraced therein.
