U.S. patent application number 14/502151 was filed with the patent office on 2016-10-06 for method for preparing an optimum density termite bait composition.
The applicant listed for this patent is BASF Corporation. Invention is credited to Jeffrey A. Martin, Ronald O. Richardson.
Application Number | 20160286812 14/502151 |
Document ID | / |
Family ID | 27658260 |
Filed Date | 2016-10-06 |
United States Patent
Application |
20160286812 |
Kind Code |
A9 |
Martin; Jeffrey A. ; et
al. |
October 6, 2016 |
METHOD FOR PREPARING AN OPTIMUM DENSITY TERMITE BAIT
COMPOSITION
Abstract
A composition in compacted form for use for termite monitoring
and control comprises a cellulose material which may be purified
cellulose or micro-crystalline cellulose as a base bait, the
composition being compacted to an optimum density of not less than
approximately 1.033 g/cc. Also disclosed is a method for monitoring
and controlling termite infestations which comprises the steps of
a) preparing such a composition; b) placing the composition in a
bait station; c) monitoring the station at periodic time intervals
for termites; and d) upon observing termite infestation in the bait
station, replacing the above composition with a bait composition
containing a termite killing agent.
Inventors: |
Martin; Jeffrey A.;
(Manchester, MO) ; Richardson; Ronald O.;
(Ellisville, MO) |
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Applicant: |
Name |
City |
State |
Country |
Type |
BASF Corporation |
Florham Park |
NJ |
US |
|
|
Prior
Publication: |
|
Document Identifier |
Publication Date |
|
US 20160088843 A1 |
March 31, 2016 |
|
|
Family ID: |
27658260 |
Appl. No.: |
14/502151 |
Filed: |
September 30, 2014 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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13725207 |
Dec 21, 2012 |
8881448 |
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14502151 |
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11470176 |
Sep 5, 2006 |
8720108 |
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13725207 |
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10059564 |
Jan 29, 2002 |
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11470176 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A01N 25/34 20130101;
A01M 2200/011 20130101; A01M 1/026 20130101; A01M 1/2011 20130101;
A01N 47/34 20130101; A01N 25/34 20130101; A01N 25/10 20130101; A01N
25/34 20130101; A01N 47/34 20130101; A01N 47/34 20130101; A01N
25/006 20130101; A01N 25/006 20130101 |
International
Class: |
A01N 47/34 20060101
A01N047/34; A01N 25/00 20060101 A01N025/00; A01N 25/34 20060101
A01N025/34; A01N 25/10 20060101 A01N025/10 |
Claims
1. A method for preparing an extruded composition for use for
termite monitoring and control, the method comprising extruding a
composition comprising a cellulose material and an active
ingredient for killing or controlling termites to a density of not
less than 1.033 g/cc.
2. A method as set forth in claim 1 wherein said cellulose material
is purified cellulose.
3. A method as set forth in claim 1 wherein said cellulose material
is micro-crystalline cellulose.
4. A method as set forth in claim 1 wherein said active ingredient
for killing or controlling termites is selected from the group
consisting of chitin synthesis inhibitors, juvenile hormone mimics,
stomach toxicants, contact insecticides and mixtures thereof.
5. A method as set forth in claim 4 wherein said synthesis
inhibitor is selected from the group consisting of hexaflumuron,
flufenoxuron, lufenurin, and dimilin.
6. A method as set forth in claim 1 wherein said active ingredient
for killing or controlling termites is present in the extruded
composition in a concentration from 0.01% to 10% by weight.
7. A method as set forth in claim 1 wherein said extruded
composition additionally contains a termite attractant and/or
pheromone.
8. A method as set forth in claim 1 wherein said extruded
composition has a density of 1.196 g/cc.
9. A method for controlling termite infestations comprising the
steps of: (a) compacting a composition comprising a cellulose
material and an active ingredient for killing or controlling
termites by extrusion to a density of not less than 1.033 g/cc; and
(b) placing said extruded composition in a bait station.
10. A method as set forth in claim 9 wherein said cellulose
material is purified cellulose.
11. A method as set forth in claim 9 wherein said cellulose
material is micro-crystalline cellulose.
12. A method as set forth in claim 9 wherein said active ingredient
is selected from the group consisting of chitin synthesis
inhibitors, juvenile hormone mimics, stomach toxicants, contact
insecticides and mixtures thereof.
13. A method as set forth in claim 12 wherein said synthesis
inhibitor is selected from the group consisting of hexaflumuron,
flufenoxuron, lufenurin, and dimilin.
14. A method as set forth in claim 9 wherein said active ingredient
for killing or controlling termites is present in the extruded
composition in a concentration from 0.01% to 10% by weight.
15. A method as set forth in claim 9 wherein said extruded
composition additionally contains a termite attractant and/or
pheromone.
16. A method as set forth in claim 9 wherein said extruded
composition has a density of 1.196 g/cc.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of application Ser. No.
13/725,207 filed on Dec. 21, 2012, which is a continuation of
application Ser. No. 11/470,176 filed on Sep. 5, 2006, which is a
continuation of application Ser. No. 10/059,564 filed on Jan. 29,
2002. The disclosure of application Ser. No. 13/725,207, and
application Ser. No. 11/470,176, and application Ser. No.
10/059,564 is expressly incorporated herein by reference in their
entireties.
BACKGROUND OF THE INVENTION
[0002] The present invention relates to compositions and methods
for monitoring and controlling termite infestations and, more
particularly, to such compositions and methods which provide bait
compositions utilizing purified cellulose and/or micro-crystalline
cellulose molded or compacted into desired shapes (e.g. tablets)
with optimum density for increased bait loading capacity when
placed in termite bait stations.
[0003] Termites are well known for their destructive effects on
residences, businesses and various other structures. The damage
from termite infestations results in huge economic losses,
structural safety concerns, and destruction of architecturally
valuable structures. Prior to the 1990's, the most widely accepted
method to control termite infestation was to create a termite toxic
barrier around the structure to be protected by digging trenches or
boring holes at regular intervals and pumping in or injecting
insecticide. While this method is often effective, physical
circumstances, environmental sensitivity or other concerns make
this method of control unsuitable at times. The technology of
termite baiting was developed to overcome these disadvantages.
[0004] One strategy of the current termite baiting technology
involves burying bait stations, usually some variation of a hollow
tube with perforations and a removable top, around the perimeter of
a structure at regular intervals of 8 to 10 feet for example, and
adding some type of wood or cellulose to the station for bait or
the monitoring matrix. The stations are then monitored for termites
on a regular basis, e.g. on a monthly interval. When the wooden or
cellulose bait is observed to be infested with termites, it is
replaced with bait containing an active ingredient for killing or
controlling the termites. Typically, the active containing bait is
a paper or wood based product.
[0005] Since each bait station has to be placed underground, holes
must be dug at regular intervals. Rocky and hardpan soils can make
this operation very labor intensive and thus expensive. It is
therefore desirable to make the insertion holes as small as
possible. A hole size of approximately 2 inches or less in diameter
is the most convenient size for current conventional one man power
boring equipment. However, this 2 inch diameter hole size limits
the amount of currently available wood or active bait that can be
contained in the bait station. Currently available termite baits
are not of optimum density due to air voids in the wood and paper
product bait materials employed in the art. The bait loading
capacity of current 2 inch bait stations therefore limits the time
for monitoring and refilling the bait stations to approximately one
month or less.
[0006] Substantial labor saving would be realized if the monitoring
intervals could be extended to longer periods of time. Existing
bait station designs having diameters of 4+ inches extend the
monitoring time to 90 days, but installation requires the use of 4
inch post hole digging equipment. This in turn requires either
large heavy equipment or very labor intensive manual post hole
diggers. Both methods generate substantial amounts of soil
excavated from the holes which requires disposal that adds to labor
costs. The decreased labor costs for using such a larger bait
station do not compensate for the costs of installation.
[0007] Another benefit from extended monitoring times is that since
the station is not opened as frequently for monitoring, the
termites are disturbed fewer times. It is believed that termites
may abandon areas that are disturbed too often.
[0008] U.S. Pat. Nos. 5,096,710 and 5,300,293 are directed to bait
compositions in tablet form which comprise as essential components
(a) at least one insect-growth controlling agent; (b) dextrin with
or without (c) a plant oil. Both of these patents specifically
mention tableting pressures of about 10 to about 500
kg/cm.sup.2.
[0009] There remains a need for improved bait compositions and
methods which allow maximum bait weight to be loaded into termite
bait stations to extend the monitoring time and reduce labor
costs.
SUMMARY OF THE INVENTION
[0010] Among the several objects of the present invention may be
noted the provision of a composition in compacted form for use for
termite monitoring and control comprising a cellulose material as a
base bait, the composition being compacted to an optimum density of
not less than approximately 1.033 g/cc; the provision of such a
composition preferably compacted to the form of a tablet; the
provision of a composition which maximizes the amount of bait which
may be loaded into a termite bait station; and the provision of a
method for monitoring and controlling infestations through the use
of such a composition in compacted form. Other objects will be in
part apparent and in part pointed out hereinafter.
[0011] Briefly, the present invention is directed to a composition
in compacted form for use for termite monitoring and control
comprising a cellulose material selected from the group consisting
of purified cellulose and microcrystalline cellulose as a base
bait, the composition being compacted to an optimum density of not
less than approximately 1.033 g/cc. The invention is further
directed to a method for monitoring and controlling termite
infestations comprising the steps of (a) preparing a composition in
compacted form comprising a cellulose material selected from the
group consisting of purified cellulose and microcrystalline
cellulose, the composition being compacted to an optimum density of
not less than 1.033 g/cc; (b) placing the composition in a bait
station; (c) monitoring the station at periodic intervals for the
presence of termites; and (d) upon observing termite infestation in
the bait station, adding a bait composition containing a termite
killing agent. The invention is also directed to a method for
directly controlling termite infestations which comprises preparing
a composition as above containing a termite killing agent and
placing the composition in a bait station. Thus, protection begins
as soon as the station is placed in the ground and with the optimum
density, protection is afforded for longer periods than with
current baits.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0012] In accordance with the present invention, it has now been
found that by compacting a composition comprising purified
cellulose or microcrystalline cellulose as a base bait to an
optimum density of not less than approximately 1.033 g/cc, maximum
loading of termite bait stations may be achieved resulting in an
extension of the time period needed for monitoring and refilling
the bait stations. Through the practice of the present invention,
improvements in current termite bait application practices are
realized by first processing the termite base bait composition into
custom physical forms, such as tablet forms, with optimum densities
of not less than 1.033 g/cc which permits bait compositions shape
and form versatility and substantially greater loading of
monitoring and control bait into current commercially available
termite bait stations than current commercial baits. As can be seen
from the tableting studies presented hereinafter, the optimum
compaction/density parameters for the compositions of the invention
include a density of approximately 1.196 g/cc, an area compaction
pressure of 688.71 kg/cm.sup.2, a compaction pressure of 10,000
lbs. and a compaction ratio of 3.32.
[0013] In carrying out the practice of the invention, a composition
in compacted form is prepared, the composition comprising a
cellulose material which may be purified cellulose or
microcrystalline cellulose. The cellulose material may be a
microcrystalline cellulose in powdered form sold under the trade
designation "Lattice NT-020 Microcrystalline" cellulose having an
average particle size of 20 micrometers (FMC Corporation) or
noncrystallized cellulose sold under the trade designation "Solka
Floc" (International Fiber Corp.) having an average particle size
in the range of 20 to 100 micrometers. Other brands of purified
cellulose or microcrystalline cellulose may also be employed in the
practice of the invention. The cellulose composition is compacted
into tablets, briquets, pellets, spikes, granules or extruded forms
which may be made by tablet presses, roller compaction or other
means known to those skilled in the art.
[0014] A product such as TC-223 Termite Bait Powder (0.25% dimilin
(diflubenzuron) and the balance being "Lattice NT-020" or "Solka
Floc" cellulose) is generally well suited to termite ingestion and
provides maximum termite contact due to its fine particle size.
However, the one disadvantage it has is low bulk density which
limits the amount that can be loaded into a bait station tube to a
maximum of 27 grams with conventional packaging equipment. Termite
feed rates studies in a laboratory termite colony indicate that the
ingestion of 9 grams per week of the TC-223 formulation base is a
reasonable estimate. While in real world situations this rate will
vary dramatically due to influences such as termite species,
termite population size, alternate food sources, weather conditions
etc., the rate of 9 grams per week is used for illustration
purposes. At this rate, a conventional bait station tube filled
with 27 grams of TC-223 Termite Bait Powder would be emptied in
three weeks, substantially less than the standard one month time
used for monitoring the bait and replacing the empty bait tube. In
accordance with the present invention, the monitoring interval of,
for example, 10 weeks may be extended to 11 weeks by utilizing a
compacting pressure of 10,000 lbs., to 12 weeks by utilizing a
pressure of 15,000 lbs. and to 131/2 weeks by utilizing a pressure
of 20,000 lbs.
[0015] If the cellulose material employed is in powder form rather
than granule form, it must be deaerated either prior to compacting
or during compacting to prevent "capping" which is a condition
where a lamination of the tablet occurs when pressure is suddenly
released after the compaction process. Powder contains a large
amount of air which is compressed rather than vented during
compaction. When the pressure is released, the air returns to its
original volume causing cracks or laminations in the tablets.
[0016] In addition to the cellulose material, the composition of
the invention for use for termite monitoring and control may also
contain additional termite attractants and/or pheromones. Any
termite attractants known to those skilled in the art may be used
such as paper and other forms of cellulose.
[0017] Once the monitoring of the bait station confirms the
presence of termites, the composition in the bait station is then
filled with a bait composition containing a termite killing or
controlling agent or termiticide. Any known termite killing or
controlling agent or termiticide can be used in the practice of the
invention. These include chitin synthesis inhibitors such as
hexaflumuron, flufenoxuron, lufenurin and diflubenzuron (dimilin),
juvenile hormone mimics such as methoprene and pyriproxyfen,
stomach toxicants such as sulfuramide, abamectin, cryolite, boric
acid and alkali and alkaline earth salts of boric acid, and contact
insecticides such as thiamethoxam, imidicloprid and fipronil, or
mixtures or combinations of these agents. The termite killing or
controlling agent may be present in the bait composition in various
concentrations such as 0.01 to 10% by weight.
[0018] The following examples illustrate the practice of the
invention
Example 1
[0019] A Carver Model 3889 15 Ton Press equipped with the standard
1.125 inch inside diameter test mold kit was utilized to test
various compaction characteristics and formulation parameters. The
Carver Press employed was not equipped with heated platens on the
jaws.
[0020] The standard mold produces a tablet which fits nicely into a
standard bait tube (11/4'' inside diameter). The tube will hold 5
or more tablets depending upon the tablet height. Tablet height is
a function of formulation weight, physical form (powder or fine
granule) and compaction pressure. The formulation weight was kept
constant at 15 grams per compaction test during the evaluation.
Both TC-223 powder and fine granulation were evaluated through
several compaction pressures. De-aeration of the powder was
accomplished by filling the mold with 10 grams of powder, placing
the upper punch into the mold and lightly pressing the powder by
hand to force out the air. The remaining 5 grams then fit into the
mold. Tablet diameter and height were measured and volumes and
densities calculated.
[0021] Compaction pressures of 3300, 7500, 10000, 15000 and 20000
lbs. were tested on powder and fine granulation formulations of
TC-223. Both formulations were taken from pilot tests using a 10
cu. ft. Marion Mixer.
[0022] The results are summarized in the following table:
TABLE-US-00001 Tube Loading Com- Multi Tablet Diam- Tablet Mold
Tablet pac- Tableting Tableting Tabs Weight eter Area Height Volume
Volume Density tion Pressure in Pressure Calc. Material (gm) (cm)
(cm.sup.2) (cm) (cc) (cc) (g/cc) Ratio Pounds Kg/cm.sup.2 (gms)
Comments Tablet From 15 2.9 6.6 2.6 41.59 17.16 0.874 2.42 3300
227.21 80.19 Too soft Fine Granule NT-200 Low Loading Tablet From
15 2.9 6.6 2.2 41.59 14.52 1.033 2.86 7500 516.53 94.77 Fair
hardness Fine Granule NT-200 Fair Density Tablet From 15 2.9 6.6
1.9 41.59 12.54 1.196 3.32 10000 688.71 109.77 Hard, Fine Granule
NT-200 Good loading Tablet From 15 2.9 6.6 1.75 41.59 11.55 1.299
3.60 15000 1033.06 119.18 Very Hard, Fine Granule NT-200 Excell.
Loading Tablet From 15 2.9 6.6 1.65 41.59 10.89 1.377 3.82 20000
1377.41 126.36 Very Hard, Fine Granule NT-200 Max. Loading Tablet
From 15 2.9 6.6 1.9 41.59 12.54 1.196 3.32 15000 1033.06 109.74
Hard, Deaerated Powder Good Loading Tablet From 15 2.9 6.6 1.7
41.59 11.22 1.337 3.71 20000 1377.41 122.65 Hard, Deaerated Powder
Excel. Loading Tablet From 15 2.9 6.6 2.1 41.59 13.86 1.082 3.00
10000 688.71 99.29 Fair hardness Deaerated Powder Fair Density
Tablet From 15 2.9 6.6 2.3 41.59 15.18 0.988 2.74 7500 516.53 90.65
Fair hardness Deaerated Powder Marginal Loading Tablet From 15 2.9
6.6 2.7 41.59 17.82 0.842 2.33 3300 227.27 77.22 Too soft,
Deaerated Powder Low Loading Bayer Tube Calculated 2.9 13.9 91.77
Tablet Volume Bayer Tube Calculated 110.8 0.361 40.00 Fine Granule
Vol. Fill
[0023] From the table, it can be seen that optimum compacting
characteristics were associated with the fine granulation
formulation and that 7500 lb. compaction pressure on the granule
formulation appears to be the lower limit for obtaining an
acceptable density tablet. Using the assumed 9 grams per week
termite ingestion number, enough bait could be added to last
approximately 101/2 weeks. The desired monitoring time is at least
12 weeks (3 months). Increasing the compaction pressure to 10,000
lbs. using the fine granule formulation tableted well and gave a
much denser tablet with an approximate calculated monitoring time
of the desired 12 weeks. Compaction pressures of 15,000 lbs. and
20,000 lbs. using the fine granule formulation, again both tableted
well and extended the monitoring time to 13 weeks and 14 weeks
respectively.
[0024] Based upon the results set forth in the above table, the
optimum compaction/density parameters appear to be 10,000 lbs.
compaction pressure, a density of 1.196 gm/cc, a compaction ratio
of 3.32 and an area compaction pressure of 688.71 kg/cm.sup.2.
Example 2
[0025] The following bait composition was prepared for
tableting:
TABLE-US-00002 Dimilin 5.56 grams Solka Floc granules 94.44
grams
[0026] 40 gram slug tablets were made using the Carver Press with
2.25'' diameter die at 20,000 lbs. tableting pressure. The "slugs"
were then ground in a hand grist mill to granules. The granules
were shifted to 12/20 and 20/45 mesh sizes. Overs were hand ground
through a 12 mesh screen with a pestle. The 20/45 mesh granules
were than tableted into 5 gram 1.25'' diameter tablets using the
Carver Press at 10,000 tableting pressure.
[0027] In view of the above, it will be seen that the several
objects of the invention are achieved and other advantageous
results attained.
[0028] As various changes could be made in the above methods and
compositions without departing from the scope of the invention, it
is intended that all matter contained in the above description and
shown in the accompanying drawings shall be interpreted as
illustrative and not in a limiting sense.
* * * * *