Note: Descriptions are shown in the official language in which they were submitted.
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SPBCIFICATYON
INSECT PEST CONTROL METHOD
TECHNICAL FIELD
The present invention relates to an insect pest control
method. Mores particularly, it relates to an insect pest
control method, especially flying inaects, using a preparation-
retaining material comprising a carrier having supported
thereon a preparation containing a pe$ticidal component which
in hard to vaporite at normal temperature, in which the
pesticidal component is released from the preparation-retaining
material by making use of an air current raised by a blower
means under non-heating conditions; an apparatus suitable
therefor; and a carrier constituting the preparation-retaining
material.
HAGICGROUNd ART
A great number of pesticidal preparations have been
proposed, and a proper preparation is selected therefrom for
practical use in accordance with the insect to be controlled.
in particu].ar, preparations containing a vaporizinq pesticidal
component, i.e., those having a high vapor pressure at normal
temperature have been used for flying insects such ae
mosquitos. The problem in using vaporizing components is that
the preparations tends to vaporize and lessen 3.te effect before
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use, for example, during storage. In order to prevent a
preparation from vaporizing during storage and to let the
preparation be released in a necessary concentration upon use,
insect pest control has been carried out frequently by
vaporizing a preparation under heating conditions. The
pesticidal components contained in this type of preparations
which are used under heating conditions usually have a vapor
pressure of 1x10'3 mmHg or lower at 30 C.
As an example of insect pest control by vaporizing a
preparation under heating conditions, it is cited that a
mosquito coil is a spiral coil molded from a kneaded mixture of
a preparation and a slow-burning support, which is lit up and
burnt whereby the preparation is vaporized by the heat.
Pesticidal components useful for mosquito coils include
pyrethrin, allethrin, and empenthrin. A mat type or liquid
type electric mosquito control apparatus comprises an
appropriate support impregnated with a preparation containing
a pesticidal component, a part of the impregnated support of
which is heated with a heater and the like to release the
preparation. Pesticidal components useful for these types
include allethrin, furamethrin, and prallethrin. Pesticidal
components used in preparations for fumigation or evaporation
which release a preparation in a short-time period by heating
with a heat source, such as heat of combustion or chemical
reaction, include methoxadiazone, permethrin, and dichlorvos
(Kateiyo Sacchuzai Gairon, Japan Sacchuzai Kogyokai (1991)).
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Methods for forcibly vaporizing a preparation by
ventilation are known. To cite an example, JP-A-55-954
(unexamined published Japanese utility model application)
discloses a pesticidal apparatus having put therein a
sublimating insect repellent, such as naphthalene, which
inhales outer air through a hole to make the vaporizing
component of the repellent vaporize and discharges air
containing the vapor through a venting hole. Furthermore, a
method for killing insects in which a diffusing material
retaining a normal temperature vaporizing prepetration, which is
shaped into, e.g., a fan, is driven by a driving means to
diffuse the vaporizing preparation is also known. This mothod,
although regarded as one method for vaporizing a preparation
under non-heating conditions, is considered to be effective
when applied to preparations having relatively high
vaporizability.
In the above-cited example of the method for vaporizing
a preparation by ventilation, it is described that the air to
be blown should be hot air when a peaticidal preparation whose
vapor pressure ranges from 1x10' mmNg to lxl0"6 mmHg at 30 C is
used.
Spraying with aerosol is the only known means for
diffusing a pesticidal component having a vapor pressure of
1x10'1 mYnHg to ix10'6 mmHg at 30 C in space under non-heating
conditions for insect control.
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For control of flying insect pests, insecticides having
high insecticidal activity and a very high vapor pressure, such
as DDVP having a vapor pressure of 1x10"2 mmHg at 30 C, have
been put to practical use in the form of a vaporizing
preparation comprising a resin matrix because of simplicity of
use and also because there is no danger of increasing the
surrounding temperature or causing burns.
However, DDPV is an organophosphorus compound, the
safety of which is a concern. Therefore, vaporizing
preparations of other chemicals have been sought for. When an
insecticide other than organophosphorus compounds, for example,
empenthrin is formulated into_a vaporizing preparation, the
preparation is effective only in a confined system. It has
been used in practice only in deserted places, such as a septic
tank, and places closed for a long time, such as a wardrobe and
a chest of drawers.
As stated above, most of the insecticidal preparations
used against insect pests, especially flying insects, are
usually of the type that the active ingredient thereof is
vaporized and diffused under heating conditions. This type of
preparations require much energy and entertain a danger of
increasing the temperature of the equipment or the surrounding
temperature an,d a burn. -
Where an active ingredient of an insecticidal
preparation is to be vaporized at normal temperature without
any heating means, the active ingredient to be used must have
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a high vapor pressure at normal temperature so as to be
supplied to the space in a sufficient concentration. DDVP and
the like which have a high vapor pressure at normal temperature
have a safety problem. Thus, there has been no effective means
available as yet in which a preparation used is safe and hard
to vaporize at normal temperature, that is, does not decrease
before use but, in use, can be supplied to the surrounding
space in a sufficient concentration under non-heating
conditions.
Hence it has been keenly demanded to develop a means
for controlling insect pests which eliminates the above-
mentioned problems by vaporizing and diffusing a highly safe
active ingredient under non-heating conditions.
DISCLOSURE OF THE INVENTION
The inventors of the present invention have extensively
studied on control of insect pests by releasing under non-
heating conditions a pesticidal preparation that has usually
been used by vaporizing and diffusing the active ingredient
under heating conditions, and completed the invention.
The present invention is characterized by the
following:
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(1) An insect pest control method which comprises:
supporting on a carrier a preparation containing at least
one pesticidal component selected from among compounds having
a vapor pressure of from 1.3 x 10-5 Pa (1 x 10-7 mmHg) to 0.2
Pa (1.5 x 10-3 mmHg) at 30 C, to prepare a preparation-
retaining material;
setting the preparation-retaining material so that an air
current raised by a fan is applied to and passed into the
preparation-retaining material; and
releasing the pesticidal component from the preparation-
retaining material into the air under non-heating conditions
to control insect pests.
(2) The insect pest control method according to claim 1
wherein said pesticidal compound is selected from among 1-
ethynyl-2-methyl-2-pentenyl dl-cis/trans-3-(2,2-
dimethylvinyl)-2,2-dimethyl-l-cyclopropanecarboxylate, d-
trans-2,3,5,6,-tetrafluorobenzyl-3-(2,2-dichlorovinyl)-2,2-
dimethyl-l-cyclopropanecarboxylate, (5-benzyl-3-furyl)methyl
d-cis/trans-chrysanthemate, d-3-allyl-2-methyl-4-oxo-2-
cyclopentenyl d-trans-chrysanthemate, 5-propargyl-2-
furylmethyl d-cis/trans-chrysanthemate, (+)-2-methyl-4-oxo-3-
(2-propynyl)-2-cyclopentenyl (+)-cis/trans-chrysanthemate, dl-
3-allyl-2-methyl-4-oxo-2-cyclopentenyl dl-cis/trans-2,2,3,3-
tetramethylcyclopropanecarboxylate, and/or isomers thereof
and/or analogues thereof.
(3) An insect pest control apparatus which comprises a main
body having a ventilation means leading to a vent hole and a
preparation-retaining material comprising a preparation
supported on a carrier set at one or more locations within the
ventilation means
wherein the preparation-retaining material contains at
least one pesticidal component selected among compounds having
a vapor pressure of from 1.3 x 10-5 Pa (1 x 10-' mmHg) to 0.2
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Pa (1.5 x 10-3 mmHg) at 30 C; and an air current raised at the
vent hole is applied to and passed into the preparation-
retaining material set in the ventilation means to release the
pesticidal component under non-heating conditions.
(4) The insect pest control apparatus according to claim 3
wherein said pesticidal component is selected from among 1-
ethynyl-2-methyl-2-pentenyl dl-cis/trans-3-(2,2-
dimethylvinyl)-2,2-dimethyl-l-cyclopropanecarboxylate, d-
trans-2,3,5,6,-tetrafluorobenzyl-3-(2,2-dichlorovinyl)-2,2-
dimethyl-l-cyclopropanecarboxylate, (5-benzyl-3-furyl)methyl
d-cis/trans-chrysanthemate, d-3-allyl-2-methyl-4-oxo-2-
cyclopentenyl d-trans-chrysanthemate, 5-propargyl-2-
furylmethyl d-cis/trans-chrysanthemate, (+)-2-methyl-4-oxo-3-
(2-propynyl)-2-cyclopentenyl (+)-cis/trans-chrysanthemate, dl-
3-allyl-2-methyl-4-oxo-2-cyclopentenyl dl-cis/trans-2,2,3,3-
tetramethylcyclopropanecarboxylate, and/or isomers thereof
and/or analogues thereof.
(5) Use of an insect pest control preparation which comprises
at least one pesticidal component selected from among
compounds having a vapor pressure of from 1.3 x 10-5 Pa (1 x
10-7 mmHg) to 0.2 Pa (1.5 x 10-3 mmHg) at 30 C, said compound
being 1-ethynyl-2-methyl-2-pentenyl dl-cis/trans-3-(2,2-
dimethylvinyl)-2,2-dimethyl-l-cyclopropanecarboxylate, d-
trans-2,3,5,6,-tetrafluorobenzyl-3-(2,2-dichlorovinyl)-2,2-
dimethyl-l-cyclopropanecarboxylate, (5-benzyl-3-furyl)methyl
d-cis/trans-chrysanthemate, d-3-allyl-2-methyl-4-oxo-2-
cyclopentenyl d-trans-chrysanthemate, 5-propargyl-2-
furylmethyl d-cis/trans-chrysanthemate, (+)-2-methyl-4-oxo-3-
(2-propynyl)-2-cyclopentenyl (+)-cis/trans-chrysanthemate, dl-
3-allyl-2-methyl-4-oxo-2-cyclopentenyl dl-cis/trans-2,2,3,3-
tetramethylcyclopropanecarboxylate, and/or isomers thereof
and/or analogues thereof, as the preparation supported on a
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carrier as used in the method and/or apparatus according to
any of claims 1 to 4.
(6) A preparation-retaining material comprising a preparation
supported on a carrier and being set with the ventilation
means of the insect pest control apparatus according to claim
3, said preparation comprising at least one pesticidal
component selected among compounds having a vapor pressure of
from 1.3 x 10-5 Pa (1 x 10-' mmHg) to 0.2 Pa (1.5 x 10-3 mmHg)
at 30 C, wherein the material does not block an air current in
the ventilation means.
(7) The preparation-retaining material according to claim 6
wherein said pesticidal component is selected from among 1-
ethynyl-2-methyl-2-pentenyl dl-cis/trans-3-(2,2-
dimethylvinyl)-2,2-dimethyl-l-cyclopropanecarboxylate, d-
trans-2,3,5,6,-tetrafluorobenzyl-3-(2,2-dichlorovinyl)-2,2-
dimethyl-l-cyclopropanecarboxylate, (5-benzyl-3-furyl)methyl
d-cis/trans-chrysanthemate, d-3-allyl-2-methyl-4-oxo-2-
cyclopentenyl d-trans-chrysanthemate, 5-propargyl-2-
furylmethyl d-cis/trans-chrysanthemate, (+)-2-methyl-4-oxo-3-
(2-propynyl)-2-cyclopentenyl (+)-cis/trans-chrysanthemate, dl-
3-allyl-2-methyl-4-oxo-2-cyclopentenyl dl-cis/trans-2,2,3,3-
tetramethylcyclopropanecarboxylate, and/or isomers thereof
and/or analogues thereof.
(8) The insect pest control method and/or the insect pest
control apparatus and/or the use and/or the preparation-
retaining material according to any of claims 1 to 7 wherein
the carrier has a honeycomb structure, a structure like a
ventilation blind, a lattice structure or a network structure.
(9) The insect pest control method and/or the insect pest
control apparatus and/or the use and/or the preparation-
retaining material according to any of claims 1 to 8 wherein
the carrier is a molded article obtained from paper, resins,
ceramics, glass fiber, carbon fiber, chemical fiber, natural
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fiber, nonwoven fabric made of glass fiber, carbon fiber,
chemical fiber or natural fiber, porous glass materials or
metallic nets.
As previously described, a method for vaporizing an
pesticidal component from a preparation containing the same by
blowing air thereby to control flying insects is known.
However, preparations applicable to this method have been
limited to those having a very high vapor pressure such as
DDVP, or the method has been limited to use in a confined
space. It has been believed impossible for a pesticidal
component which is hard to vaporize at normal temeperature and
has a vapor pressure of not higher than 1 x 10-3 mmHg at 30 C
to be released from a preparation containing the same in a
concentration sufficient for insect pest control only by
blowing air under non-heating conditions. Therefore, it has
been far from anticipation that use of a preparation
containing a pesticidal component which is hard to vaporize at
normal
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temperature might produce an insecticidal effect in Nide spaces
such as a living room.
This seems to be partly because the right vapor
pressures of many known pesticidal components at various
temperatures have not determined, still less compared
accurately.
The inventors of the present invention analysed the
vapor pressure at 30 C of many compounds acting as a pesticidal
component by using a cox diagram hereinafter described. In
their study, a preparation-retaining material was prepared by
supporting, on an appropriate carrier, a preparation containing
a pesticidal component which Kas selected by taking the vapor
pressure as a measure, and air was blown to the resulting
preparation-retaining material s t in a place to release the
peeticidal component therefrom. As a result, the inventors
unexpectedly found the method of the present invention. That
is, when the preparation-retaining material is s t, and air is
applied thereto under non-heating conditions, the pesticidal
component which is hard to vaporise is released therefrom,
whereby insect peats such as flying insects can be controlled
by the thus released component.
Embodiments of supporting a preparation containinq a
pesticidal component (incluaive of a component which inhibits
a biting action of biting insects) on a carrier include, as
hereinafter described in detail, not only a method in which the
preparation is applied to a carrier, such as paper, porous
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resins, ceramics and the like, the resultinq preparation-
retaining material is put in a case, and air is applied to the
preparation-retaining material as put in the case and set, but
also a method in which a liquid preparation containing the
posticidal component is put in a bottle having the above-
described carrier, such as paper and porous resins, in the form
of, e. g. , a sheet, which is pulled up out of the opening of the
bottle so that the liquid may be sucked up, and air is applied
to the carrier outside the bottle.
The conventionel method in which a normal temperature
vaporiaing pesticidal component is vaporized without heating
and letting out the vapor of the component from a vent hole is
disadvantageous in that the vapor concentration is difficult to
control. The conventional method in which a fan-shaped
diffusing material retaining a vaporizing preparation ia driven
by a driving means to diffuse the vaporizing preparation is
disadvantageous in that a burden is imposed on the driving
means to damage it. Besides, the method of driving a diffusing
material retaining a vaporizing preparation by a driving means
is applicable only to normal temperature vaporizing
preparations or effective only when used with warm air blowing
conditions.
The method of the present invention comprises
supporting a preparation containing a pesticidal component
which is hard to vaporize at normal temperature on a carrier,
contacting the preparation-retaining material in a fixed state
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with an air current by a blower means to release the posticidal
component, and controlling flying insects with the thus
released preparation. Accordingly, the method of the present
invention has such characteristics that the concentration of
the vaporized component can be controlled easily and, since no
heating means is used, there is no danger, and the apparatus
therefor can be simple. The method is therefore an excellent
means for releasing a posticidal component.
The means for feeding air to the preparation-retaining
material containing a posticidal component may be a simple one,
such as a fan that can be driven by a cell, as well, as a blower
means suitable for stable release of the preparation in a
constant concentration over a long time period, e.g., for 30
days from the start of blowing. The details of the blower
means will be described later.
The insect pest control is intended to inclusively mean
extermination of insect pests, repelling insect pests, and
inhibition of a blood sucking action or a biting action in
blood-sucking insects. Emphasis should be placed here on the
following points. (1) It has been found that the pesticidal
components for use in the present invention show straight lines
parallel to each other in their vapor pressure vs. temperature
plots in a cox diaqram. (2) eased on this result of study, it
has now been made possible to evaluate the posticidal effect of
various compounds, inclusive of those which have only one known
vapor pressure in a tamperature range of from 20 C to 50 C,
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when applied to the "method of releasing a pesticidal component
only by blowing under non-heating conditions", by taking "the
vapor pressure at a given temperature (30 C)" as a common
standard of evaluation. As a result, a new finding was
obtained, based on which a new technique has been established.
An example of the cox diagram prepared on various
pesticidal preparations is shown in Fig. 11.
In Fig. 11, a: DDVP; b: nitrapyrin; c: empenthrin; d:
demeton-D; e: terallethrin (M 108); f: furamethrin; g: aidrin;
h: prallethrin; i: allethrin; j: phosphamidon; k: methoprene;
1: fluchloralin; m: resmethrin; n: tetramethrin; o: phenothrin;
p: cyphenothrin; q: permethrin; r: S-fenvalerate; s:
phthalthrin; and t: flucythrinate.
The vapor pressures of pyrethroid compounds measured at
every 5 C between 20 C and 40 C are shown in Table 1 below.
The measurement was made with the vapor pressure measuring
apparatus shown in Fig. 12 (the detailed explanation of the
apparatus are omitted here) which is described in Kagaku Kogyo
Jikkenho (4th ed.), Baifukan (1986). in Table 1, the
underlined data are those from the literatures.
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TABLE 1
Vapor Pressures of Pyrethroid Compounds
Vapor Pressure (mmHQ )
Compound 20 C 25 C 30 C 35 C 40 C
prallethrin 3.5x10'5 6.9x10'5 1.3x10'4 2.4x10"4 4.4x10'4
allethrin 3.4x10"5 6.3x10"5 1.2x104 2.2x10'4 4.0x10'a
phthalthrin 3.5x10'8 6.6x10'8 1.2x10'' 2.2x10'' 3.8x10'I
resmethrin 3.5x106 7.1x10'6 1.7x10'S 2.8x10"3 5.6x10'5
phenothrin 1.2 x10'6 2. 2 x 10'6 4. 3 x 10'b 7. 7 x 10'6 1. 4 x10'S
permethrin 5.5x10'' 1.1x10'6 1.9x106 3.6x10'6 6.3x10"6
cyphenothrin 9.2x10'' 1.9x10'6 3.6x10'6 6.6x10'6 1.3x10"5
empenthrin 5.1x10"4 9.2x10'4 1.6x103 2.8x10"3 4.8x10'3
DDVP 1.2X102 1.9x10'2 3.0x10'2 4.6x10"2 7.1x101
benfluthrin 8.3x10"5 1.5x10"4 2.7xl04 4.0x10"4 8.5x10'4
furamethrin 1.3x10"4 2.2x10'4 4.5x10'4 7.1x10"4 1.4x10'3
tetramethrin 2.4x10'6 4.4x10'6 8.5x10-6 1.7x10"5 3.2x10'5
terallethrin 2.2x10'4 4.2x10'4 6.6x10"4 1.2x10'3 4.8x10'3
(M 108)
Note: The underlined data are from the literatures.
The vapor pressure data are available in the following
literatures.
(i) Noyakuno seizaigijutsu to kiso, Nihon Shokubutsu Boeki
Kyokai (1985)
(ii) Noyaku Data Book, Soft Science K.K. (1989)
(iii) Safety data (for terallethrin)
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(iv) Product data (for furamethrin, tetramethrin and
resmethrin)
Compounds which are hard to vaporize at normal
temperature can be used in the present invention as a
pesticidal component. Those having a vapor pressure higher
than 1x10-7 mmHg at 30 C and a boiling point of not lower than
120 C/1 mmHg are preferred. It should be noted that the range
of vapor pressure as referred to herein is the range at 30 C on
the vapor pressure vs. temperature plot in the cox diagram
hereinafter described.
The vapor pressure of pesticidal components has
conventionally been measured at an arbitrarily and randomly
selected temperature, that is, under non-fixed measuring
conditions. Usually, the measurement has been made at a
temperature of from 10 C to 50 C. It has therefore been
difficult to compare a plurality of pesticidal preparations in
terms of vapor pressure.
The results of our study have made it possible to
suppose or know the vapor pressure at a target temperature by
utilizing the cox diagram only if at least one found value is
available. The aforesaid problem can thus be solved.
The cox diagram is illustrated below in detail.
When vapor pressure P is measured at varied temperature
t for a large number of chemical substances, and log P(wherein
P is a vapor pressure (mmHg)) is plotted as ordinate, and
t/(t+C) [wherein t is a temperature ( C); and C is a constant
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(usually 230 )] as abscissa, it is known in engineering that the
plot shows linearity with high precision.
In other words, a large number of chemical substances
have the following relationship between temperature t and vapor
pressure P at that temperature.
logP = D + Et/(t + C)
Accordingly, the plot of logP as ordinate against t/(t+C) as
abscissa gives a straight line.
The cox diagram as used herein is the straight line or
a group of the straight lines obtained by plotting log P as
ordinate and t/(t+C) as abscissa on a graph.
Among the pesticidal components whose vapor pressure
has been measured within a temperature range of from 20 C to
40 C, those having a vapor pressure of higher than 1x10'7 mmHg
at 30 C in the above-mentioned cox diagram, being hard to
vaporize at normal temperature, and having a boiling point of
not lower than 120 C/1 mmHg are preferred. Furthermore, from
the standpoint of safety, pyrethroid compounds are preferred.
Typical examples of these preferred compounds are shown below:
dl-3-allyl-2-methyl-4-oxo-2-cyclopentenyl di-cis/trans-
chrysanthemate (common name: allethrin; trade name: Pynamin,
produced by Sumitomo Chemical Co., Ltd.);
d1-3-4llyl-2-methyl-4-oxo-2-cyclopentenyl d-cis/trans-
chrysanthemate (trade name: Pynamin Forte, produced by Sumitomo
Chemical Co., Ltd.; hereinafter referred to as "pynamin
forte");
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dl-3-allyl-2-methyl-4-oxo-2-cyclopentenyl d-trans-
chrysanthemate (trade name: Bioallethrin, produced by Uclaf
Co.);
d-3-allyl-2-methyl-4-oxo-2-cyclopentenyl d-trans-
chrysanthemate (trade name: Exthrin, produced by Sumitomo
Chemical Co., Ltd.; trade name: Esbiol, produced by Uclaf Co.;
hereinafter referred to as "esbiol");
(5-benzyl-3-furyl)methyl d-cis/trans-chrysanthemate
(common name: resmethrin; trade name: Chrysron Forte, produced
by Sumitomo Chemical Co., Ltd.; hereinafter referred to as
"resmethrin");
5-propargyl-2-furylmethyl d-cis/trans-chrysanthemate
(common name: furamethrin; trade name: Pynamin D Forte,
produced by Sumitomo Chemical Co., Ltd.; hereinafter referred
to as "furamethrin");
(+)-2-methyl-4-oxo-3-(2-propynyl)-2-cyclopentenyl
(+)-cis/trans-chrysanthemate (common name: prallethrin; trade
name: Etoc, produced by Sumitomo Chemical Co., Ltd.;
hereinafter referred to as "prallethrin");
dl-3-allyl-2-methyl-4-oxo-2-cyclopentenyl dl-cis/trans-
2,2,3,3-tetramethylcyclopropanecarboxylate (common name:
terallethrin; produced by Sumitomo Chemical Co., Ltd.;
hereinafter referred to as terallethrin);
(1,3,4,5,6,7-hexahydro-1,3-dioxo-2-isoindolyl)methyl
dl -cis /trans -chrysanthemate (common name: phthalthrin; trade
name: Neopynamin, produced by Sumitomo Chemical Co., Ltd.);
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(1,3,4,5,6,7-hexahydro-1,3-dioxo-2-isoindolyl)methyl
d-cis/trane-chryaanthemate (trade namee Neopynamin Forte,
produced by Sumitomo Chemical Co., Ltd.)=
3-phenoxybenayl-d-ci$/trana-chrysanthemate (coxmeon
names phanothrin; trade names Sumithrin, produced by Sumitomo
Chemical Co., Ltd.);
3-pheno:cybenayl-dl-cie/trane-3-(2,2-dichlorovinyl)-2,Z-
dimethyl-l-cyclopropanecarboxylate (common name: permethrin=
trade names Eksmin, produced by Sumitomo Chemical Co., Ltd.);
(t) c:-cyano-3-phenoxybenayl(+)-cia/trana-chzysanthesate
(comtaon name: cyph nothrin; trade name: Gokilaht, produced by
Sumitomo Chemical Co., Ltd.);
1-ethynyl-2-methyl-2-pentenyl dl-cis/trans-3-(Z,2-
dimethylvinyl)-2,2-dimethyl-l-cyclopropanecarboxylate (common
names ampenthrin= trade nantee Vaporthrin, produced by Sumitomo
Chemical Co., Ltd.; hereinafter referred to as "empenthrin").
in addition, compounds which are structurally similar
(i.e., analogous) to the above-liated compounde can also be
used. For mpenthrin having two methyl groups at the
3-position, for instance, analogues having other alkyl groups,
unsaturated alkyl groups or halogen atoms in place of the
methyl groups can be used.
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2197191
In the present invention, at least one pesticidal
component selected from these compounds 3.a used in the form of
a preparation-retaining material.
Of the above-listed compounds particularly preferred
are empenthrin, prallethrin, resmethrin, esbiol, furamethrin,
and terallethrin. Aa long as the above-described conditions
are satisfied, other pesticidal componente, such aa
organophosphorus compounds, carbamate compounds,, and insect
growth inhibitory agents ( IGR, JH and the like ), can be used
alone or in combination with no particular limitation.
Analogues to these compounds are also useful.
The carrier which constitutes the preparation-retaining
material of the present invention preferably has good
ventilation so as not to block the air current from a blower
means nor to dif fuse the air current in unnecessary directions.
it is desirable for the carrier to retain a sufficient amount
of a preparation (p sticidal component and the like). Any
material that has good ventilation and can retain a sufficient
amount of a preparation can be used with no particular
limitation.
Carriers havinq a honeycomb structure, a structure like
a ventilation blind, a lattice structure, a network structure
or the like are preferred for their structural simpleness and
good ventilation.
r
r 19
CA 02197191 1997-02-10
2 19719 1
The carrier to be used usually has such ventilation as
has an air permeability of not less than 0.1 Q/sec, preferably
not less than 0.1 Q/sec.
The carrier can be made of organic or inorganic molding
materials. Molded articles obtained from these materials as a
carrier include paper (e.g., filter paper, pulp, cardboard and
the like), resins (e.g., polyethylene, polypropylene, polyvinyl
chloride, oil-absorbing polymers and the like), ceramics, glass
fiber, carbon fiber, chemical fiber (e.g., polyester, nylon,
acrylic resins, vinylon, polyethylene, polypropylene and the
like), natural fiber (e.g., cotton, silk, wool, hemp, and the
like), and nonwoven fabric made of glass fiber, carbon fiber,
chemical fiber, natural fiber and the like, porous glass
materials, metallic nets and the like.
One of these carriers in which a preparation containing
the pesticidal component is retained or a combination of two or
more thereof is used in an arbitrary shape.
A carrier for adsorption (i.e., an auxiliary material
for retaining a preparation on a carrier) can be used in
combination. Such a carrier for adsorption includes gelling
material (e.g., agar, caragenan, starch, gelatin, alginic acid
and the like) and plasticized high polymers. High polymers can
be plasticized with, for example, dioctyl phthalate.
The vaporizing properties of the preparation can be
improved by addition of a sublimating substance, such as
adamantane, cyclododecane, cyclodecane, norbornane,
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trimethylnorbornane, naphthalene, and camphor, as a
vapoXiaation accelerator. Aleo, the preparation may contain a
synergiet known for an active pyrethroid component, such as a-
[2-(2-butoxyethoxy)athoxy]-4,3-methylenedioxy-2-propyltoluene
(piperonyl butoxide), N-(2-ethylhexyl)bicyclo[2,2,1]hept-5-ene-
2,3-dicarboximide (MGx-264), octachlorodiisopropyl ether (S-
-421), synepirin 500 and the like.
zn order to increase stability to light, heat, and
oxidation and thereby to stabilize the effect, an antioxidant
or an ultraviolet absorber can be added to the preparation.
Useful antioxidants include 2'-methylenebi,s(6-t-butyl-4-
ethylphenol) 2,6-di-t-butyl-4-methylphenol (BHT), 2,6-di-t-
butylphenol, 2,2'-methylenebis(6-t-butyl-4-methylphenol),
4,4'-m thylanebia(2,6-di-t-butXlphenol), 4,4'-butylidenebis(6-
t-butyl-3-taethylphenol ) , 4, 4 1-thiobis ( 6-t-butlrl-3-
methXlphenol), and dibutyihydroxinone (DBH). Useful
ultraviolet absorbers include phenol derivatives (e.g., BHT),
bisphenol derivatives,arylamineA (e.g., phenyl-a-naphtylamine,
a condensate between phenetidine and acetone), and benaophenone
compounds.
In the embodiment in which the preparation is
absorbed and retained in the preparation-retaining
material and is vaporiaed by feeding air or the like,
an indicator directly or indirectly indicative of the residual
amount of the preparation can be used. For example, a function
as an indicator can be added to the carrier by uisinq a dye that
-
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causes the carrier to change its color, such as
allylaminoanthraquinone, 1,4-diisopropylaminoanthraquinone,
1,4-diaminoanthraquinone, 1,4-dibutylaminoanthraquinone,
1-amino-4-anilinoanthraquinone, and the like. A function of
indicating the residual amount of the preparation can also be
added by using an electron-donating organic compound having a
lactone ring or a color developer having a phenolic hydroxyl
group, and, if desired, a desensitizer; these compounds cause
the carrier to change its color with vaporization of the
preparation (and the desensitizer vaporizing at the same time).
Perfumes generally used in compositions for vaporization may be
added to the preparation.
In the embodiment in which a liquid preparation is put
in a bottle and sucked up by absorption in a carrier in the
outside of the bottle, and air is blown to the carrier outside
the bottle to vaporize the preparation, there is no need to use
an indicator as far as the bottle allows confirmation of the
residual amount of the liquid contained therein.
The preparation (containing the pesticidal component,
and the like) can be retained in or on a carrier by applying a
liquid preparation to the carrier by dropping, impregnation,
spraying, printing, brush or the like coating, or by sticking
a preparat~on onto the carrier. In-using a non-liquid or
solventless preparation, it can be applied to a carrier by
kneading, coating, printing or the like. Also, the preparation
may be applied either all over the carrier or partly, i.e., the
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preparation may be applied in spots or pattern or applied to
only one aide of the carrier.
In another embodiment of retaining the preparation in
a carrier, the preparAtion is charged in a bottle for liquid
and is migrated to a vaporizing zone through a porous carrier.
In order to facilitate application of a liquid
preparation to the carrier by impregnation, an organic solvent,
such as fatty acid esters (e.g., isopropyl myristate, isopropyl
palmitate, hexyl laurate or the like), isopropyl alcohol,
polyethylene glycol, deodorized kerosine, and the like, can be
used if desired as an additive for reducing the viscosity.
The amount of the pesticidal component and/or other
various components to be retained on/in the carrier is not
particularly limited. Where an oil-absorbing material (e.g.,
paper) is used as a carrier, for instance, the preparation
(containing the pesticidal component and the like) is
infiltrated into the carrier in an amount of from 50 to
1000 mg, preferably of from 100 to 700 mg, per gram of the
carrier. The above range corresponds to a range of from the
minimum for assuring a minimum rate of vaporization of
0.1 mg/hr up to a point of eaturation.
As shown in Fig. Z, the apparatue according to the
present invention has an air passageway indicated by reference
numeral 13 and vent holes (air intake 12 and vapor outlet 14).
Where the preparation-retaining material, is set in air
passageway 13, it ia fixed at at least one location in the air
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CA 02197191 1997-02-10 2 19 i' 191
passagway (indicated by reference numeral 5 in Fig. 1 and
reference numeral 30 in Fig. 2). The manner of fixing the
preparation-retaining material (5 or 30) in airy passageway 13
is not particularly limited. For example, a groove, a guide,
a stabilizing tool, or a holding element for fixing the carrier
can be provided in the air passageway.
The ventilation means used here, specifically the air
passagmray, is a passageway or a space in which an air current
raised at the vent holes rune. However, the passageway is not
always necessary. The vent holes include an air intake for
letting in outside air and a vapor outlet for letting out the
air having been let in.
The air current is explained below by referring to
Figs. 1 and 2. The apparatus is fitted with a driving means,
such as a motor, a spiral spring or the like, and equipaent
usually called a blower having such a shape, a form and a
function as i,s commonly recognized as a fan, such as a
propeller fan (indicated by reference numeral 6 in Fiq. 1 and
reference numeral 20 in Fig. 2). The fan is operated by the
driving means to suck in outside air through the air intake.
The air sucked in moves through the passageway toward the vapor
outlet. Since revolution of the fan is accompanied by eddies,
the air sucked in from the air intake is characterized in that
the current rate becomes slower toward the center of the fan
and faster toward the periphery of the fan. Accordingly, the
amount of air applied to the carrier retaining the preparation
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is smaller in the vicinities of the center of the carrier and
larger in the peripheral portions. It follows that the
diffusion of the vapor of the preparation at various parts of
the carrier is non-uniform. To cope with this problem, it ie
desirable to put a current regulator (for example, the member
shown in Fig. 4 with reference numeral 40) in the air
passageway. The current regulator is provided for leveling the
current of air applied to the preparation-retaininq material,
but it should have such a shape as minimizes a pressure loss so
as to minimize the power for revolution of the fan.
The air having been applied to the preparation-
retaining material is discharged outside, whereby the active
inqredient of the preparation is released from the preparation-
retaining material set in the air passageway, made to current,
let out through the vapor outlet, and diffused outside together
with the air current.
For practical use, a small-sised blower suffices for
such a space as a living room of common houses. Specifically,
a fan is used at about 500 to 10000 rpm, and a motor or a
spiral spring can be used as a driving means. A piezoelectric
fan that does not rely on a motor or a spring can also be used.
For use in a space like a living room, use of a fan that can be
driven with a small motor powered by a solar battery, a
secondary battery or a dry battery produces a eufficient
effect. Where a dry battery is insufficient for a long-term
use, a reChargeable battery may be used, or driving energy can
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be obtained continuously from a power source through a cord
with a plug.
A centrifugal fan is generally used. The performance
of a fan depends on not only its shape but the shape of a
partition placed at the rear of the fan.
The shape of a fan is not limited to a screw or a
propeller, and a waterwheel type fan, a rotary fan and the like
can also be used. A screw fan, a propeller fan and the like
are suitable for obtaining a large blowing action, having an
advantage that the degree of vaporization can be increased by
blowing. In order to increase the air brought into contact
with a fan, each blade of the fan may have openings. For
example, a large number of openings are made in the blades to
efficiently vaporization and diffuse the preparation. The
openings can have a variety of forms, such as a network shape,
a lattice shape, a honeycomb shape and the like. The openings
are preferably provided as uniformly as possible. The shape of
the blades is decided according to the shape of the fan. Not
only a mere plate but a hollow blade may be used.
Of various types of fans, what we call a sirocco fan 42
shown in Fig. 5 is preferably used. The fan 42 has adjustable
blowing ability with variations of a power source including
from batteries to adapters and of the voltage applied. The air
current is also adjustable by altering the shape of the fan.
For example, the air current can be increased by increasing the
diameter or thickness, and vice versa.
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The air intake is preferebly located as near as
possible to the front of the impeller but may be slightly
shifted in relation to the position where a preparation-
retaining material is to be set.
The vapor outlet is preferably provided in the
circumferential direction for efficient diffusion of the vapor
outside. The outlet is provided in at least one direction.
When smoother diffusion is required, the vapor outlet is
provided in two to f our directions thereby to dif f use the vapor
throughout the space. Tn a conventional system in which a
carrier having supported thereon a vaporizing preparation is
placed near the vapor outlet, where the vapor outlet is
provided around the whole circumference of the apparatue, the
carrier should be provided around the whole circumference of
the apparatus. This is not necessary in the present invention,
and yet the preparation can be diffused toward every direction.
zf desired, guides can be provided to control the air current
so that the vapor of the preparation may not be diffused ineide
around the circumference, for example, may be d3.scharged in
only one direction.
Where such a fan as a sirocco fan is used, the
preparation-retaining material is placed in the front of the
fan unlike the embodiments shown in Figs. 1 and 2. Therefore,
it is desirable to use an air--permeable carrier so that the air
current sucked in may not be cut or hindered and diffused
outward.
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Whether the preparation-retaining material in set in
the air intake side or vapor outlet vide of the fan appears to
make no difference. xowever, when it is aet in the intake side
of the fan, the speed of air current applied to the
preparation-retaining material 1.s relatively uniform
irrespective of the part thereof, whereas if it is set in the
outlet side of the fan, the air curXent greatly varies in speed
from part to part, while dependent on the shape of the fan.
Accordingly, it in desirable in the latter case that the air
current in made uniform by, for example, providing a current
regulator in the air passageway as described previously.
The preparation-retaining material in preferably set in
the air intake al,de because, if not, vaporization of the
preparation tends to vary greatly with place. The position of
the preparation-retaining material does not need to be right in
front of the fan and may be shifted therefrom slightly,
provided that the preparation-retaining material is in the air
current sucked in through the intake toward the fan.
in more detail, the distance bQtween the fan as a
blowing means and the carrier supporting the preparation is
preferably not so close to each other, and they are preferably
spaced at about 5 mm or more. If they are so close to each
other, it in difficult to apply air uniformly all over the
carrier, tending to result in unevenness of vaporization, i.e.,
insufficient vaporization at the peripheral portion ae compared
with the central portion. For example, in the case where a
-
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paper-made honeycomb structure (70 x 70 x 15 mm) is used as a
carrier, and air is blown with a sirocco fan (5 cm in diameter;
2 cm in thickness), when the power voltage for driving the fan
is varied from 2.0 V to 4.0 V, a preferred distance between the
carrier and the f an is 5 to 15 mm. The above range of the
distance is not limitative, and the distance can be selected
appropriately according to the shapes of the carrier and the
fan, the power voltage, the shape and size of the apparatus,
the relation among these factors, a combination of these
factors, and the like.
The effectiveness of the fan type insect pest control
apparatus of the present invention was tested as follows. As
shown in Fig. 6, the apparatus was placed on the center of the
floor of a room having a capacity of 36 m3. After the release
of the preparation was started, air in the room was sucked up
at a constant amount of 25 Q over a 20 minute period, and the
active ingredient was trapped in a silica gel trap and
quantitatively analyzed.
The trap was set 100 cm away from the side wall and
150 cm high from the floor. The concentration of the active
ingredient per m3 of air was calculated from the amount of the
collected active ingredient in accordance with the following
formula: Airborne Concentration of Active Ingredient ( g/m3)
= R x (1000 (Q) / 25.0 (Q) x 20 (min)]
- 29 _
CA 02197191 1997-02-10 ='fP
wherein R is the amount of the collected active ingredient
( g)=
In the above test, empenthrin was used as an active
ingredient.
The results obtained were compared with those of the
test conducted in the same-manner but using a conventional
liquid type electric mosquito control apparatus.
Furthermore, a fan type insect pest control apparatus
having fitted thereto a honeycomb carrier (66 x 66 x 15 mm)
impregnated with 4.3 g of empenthrin and 0.2 g of Irganox 1010
was placed in a room having a capacity of 24 m', and the fan
was driven at 1220 to 1250 rpm, at 25 C, and at a constant
voltage of 3 V. Air of the room was sucked up and trapped by
a silica gel trap in the same manner as described above (i.e.,
25 Qlmin for 20 minutes to trap 500 Q of air in total). An
average airborne concentration of the active ingredient was
obtained from the result of the air collected at a height of
150 cm and that at a height of 75 cm. The results of the
liquid type electric mosquito control apparatus were used as a
standard for comparison. The state of vaporization for 12
hours from the start of release is shown in the graph of Fig.
7, in which o indicates the airborne concentration of empenthrin
(driven at a constant voltage of 3 V), and = indicates the
airborne concentration of prallethrin (liquid type electrical
mosquito control apparatus).
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The release of empenthrin in long-term intermittent
running of the fan type insect pest control apparatus (12 hours
a day for consecutive 30 days) was also observed in the same
experimentation system. The results obtained over the testing
period of from the start of release up to 360 hours are plotted
in the graph shown in Fig. 8. The graph also includes the
comparative results obtained from the liquid type electric
mosquito control apparatus put in the room shown in Fig. 6 at
the same position as the fan type insect pest control apparatus
and electrically heated to vaporize the liquid preparation. In
the graph of Fig. 8, o indicates the vaporization amount of
empenthrin (driven at a constant voltage of 3 V), and e
indicates the vaporization amount of prallethrin (liquid type
electric mosquito control apparatus).
It is seen from both Figures that the fan type insect
pest control apparatus releases a larger amount of the active
ingredient than the liquid type electric mosquito control
apparatus and attains an equilibrium concentration within the
first 30 minute period and thereafter keeps releasing uniformly
and stably over 360 hours.
If the blowing operation in the fan type insect pest
control apparatus of the present invention is controllable, the
amount of the preparation to be released could thereby be
controlled, which will not only ensure further improvement in
uniformity and stability of vaporization but, under some
situations, make it feasible to control an increase and a
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decrease of the amount vaporized with time (from daytime to
nighttime). The fan type insect pest control apparatus was
experimentally run while controlling blowing by using a circuit
for controlling the quantity of electricity supplied from a
power source as shown in Fig. 9. The above-described
empenthrin preparation was released for a 12-hour testing
period by continuous blowing or by controlled intermittent
blowing (repetition of 2-hour blowing followed by 10-minute
suspension). The results obtained are shown in Fig. 10. The
results prove that the active ingredient airborne concentration
can be maintained constant even though the blowing cycle is
under control.
The control circuit of Fig. 9 is explained below.
The control circuit comprises DC power source 101 which
converts the power from a commercial power source to a
prescribed DC voltage; frequency distinguishing part 103 which
distinguishes commercial power frequencies; frequency dividing
part 106 which divides the commercial power frequency into 5 or
6 based on the distinction made by frequency distinguishing
part 103 to obtain reference pulses of 10 Hz; pulse producing
part 107 which sends pulses for a prescribed period of time
based on the output of frequency dividing part 105; luminance
modulating part 111 for lighting or blinking light-emitting
diode (LED) 109 for externally displaying the operating state
of the apparatus; thyristor 115 which feeds power to driving
motor 113; zerocross control part 117 which controls thyristor
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115 at zero voltage; and mode controller 119 which instructs
luminance modulator 111 on blinking or lighting in accordance
with an external operation and also conduct trigger control on
zerocross control part 117 so as to fire a triac based on the
previously set sequence.
By using the control circuit, an appropriate blowing
control mode can be put in mode controller 119, and the triac
is triggered via serocrosa control part 117 thereby to control
the operation of the blomr.
On user's choice of sequence mode according to the
necessity, the operation of the blower is controlled based on
the chosen sequence mode, and vaporization of the preparation
is controlled accordingly.
The circuit is also provided with a manual proqram
setting function for allowing a user to set a sequence moda
arbitrarily.
While the position of the preparation-retaining
material in the air passageway may be either on the air intake
side or the vapor outlet side of the blowing means, the latter
position ia preferred because the air current applied to the
carrier is relatively uniform irrespective of the position of
the carrier within the air passageway. In this case, the
carrier is set in the air current sucked up from the air intake
toward the fan.
The place in which the insect pest control apparatus is
effective is not limited. Places partitioned off to have a
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given space are preferred. For example, the apparatus is
suitably used in houses, greenhouses, septic tanks, and the
like to control the insect pests living there. Insect pests on
which the apparatus is effective include house insects, such as
flies, mosquitos, cockroaches, house dust mites, and other
disgusting insects invading from the outdoors; insects in
wardrobes or chests which are harmful to clothes, such as
tineid moths, webbing clothes moths, dermestid beetles and the
like; insects in greenhouses which are harmful to crops planted
therein; insects in livestock houses, such as biting midges,
fl.ies, mosquitos, mites and the like; and insects in septic
tanks, such as moth flies, mosquitos and the like.
Effect:
As described above, it has been generally accepted that
a pesticidal component which is hard to vaporize at normal
temperature (about 15 to 35 C) is not effective in controlling
insect pests unless it is heated at about 1100 to 170 C.
The inventors of the present invention studied the
vapor pressure vs. temperature relationship for a great number
of pesticidal components and have made it clear that the vapor
pressure-temperature relationship of the components, put in
order on a cox diagram, can be represented by straight lines
parallel to each other. Based on this result of study, it has
now been found that a preparation-retaining material in which
an insect pest control agent having a vapor pressure lower than
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1x10'1 mmHQ (1x10'' to ixl0'7 m:nHg) at 30 C on the cox diagram,
sparing vaporisablity at normal temperature, and a boiling
point of not lower than 1200CIl mentig is supported on an
appropriate carrier is, when fixed and given an air current
under non-heating conditions, capable of controlling not only
flying insect p sts but cockroaches and the like.
When the insect pest control apparatus of the present
invention is used, there is no danger of fire because no
heating is required. Furthermore, the posticidal component can
be released in a wide space in an effective concentration, and
the effect lasts long. Therefore, insect pests can be
controlled effectively.
The effect of the present invention will be
demonstrated below by way of Examples.
BRIEF $XPLANATION OF THE DRA9iING8
Fig. 1 is a schematic illustration showing one example
of an appaxatus for testing the pesticidal effect. Fig. 2 is
a schematic illustration showing one example of a fan type
insect pest control apparatus in which a posticidal preparation
is used. Fig. 3 is a perspective view of one example of a
carrier for a pesticidal preparation. Fig. 4 ia a side view of
one example of a current regulator to be used in a f an tppa
posticidal apparatus. Fig. 5 illustrates one example of a fan
type posticidal apparatus equipped with a sirocco fan. Fig. 6
schematically illustrates one example of a system for
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determining the airborne concentration of a pesticidal
preparation vaporized. Fig. 7 is a graph of the airborne
concentrations of the active ingredient released from a fan
type insect pest control apparatus and a liquid type electric
mosquito control apparatus. Fig. 8 is a graph showing the
vaporizing behavior of the active ingredient from a fan type
insect peat control apparatus and a liquid type electric
mosquito control apparatus. Fig. 9 is one example of a control
circuit for controlling the operation of the blower in a fan
type ineect pest control apparatus. Fig. 10 is a graph showing
the vaporization of empenthrin from a fan type insect pest
control apparatus with the operation of the blower controlled.
Fig. 11 is one example of a cox diagram representing the vapor
pressure-temperature relationship of pesticidal components.
Fig. 12 illustrates a method of vapor pressure measurement.
Explanation of Aeference Numbers:
1 ... Testing appnratus
2 ... Insect net
3 ... Bloper
4 ... Acrylic resin cylinder
... Preparation-retaining material
6 ... Propeller fan
7 ... Motor
12 ... Air intake
13 ... Air passageway
14 ... Vapor outlet
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15 ... Battery
16 ... Battery box
17 ... Switch
20 ... Ventilation meana (propeller)
21 ... Ventilation means (electric motor)
30 .=. Carrier (retaininq material)
31 ... Carrier cover
40 ... Current regulator
41 ... Plate
42 ... 8irocoo fan
43 ... Motor
44 ... Vapor outlet
50 ... Testinq room
51 ... Fan type ineect psst control apparatus
52 . . . Insect cage (1)
53 ... rnsect cage (2)
54 ... Silica gel trap (1)
55 ... Silica gel trap (2)
56 ... Current meter (1)
57 ... Vacuum pump (1)
58 ... Current meter (2)
59 ... Vacuum pump (2)
60 ... Sxhaust duct
81 ... Constant temperature water bath
82 ... Heater
83 ... Stirrer
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84 ... Lead wire
85 ... Condenser
86 ... Manometer
87 ... Constant pressure bottle
88 ... Water jet pump
101 ... DC power source
103 ... Frequency distinguishing part
105 ... Frequency dividing part
107 ... Pulse producing part
109 ... Light-emitting diode (LED)
111 ... Luminance modulating part
113 ... Driving motor
115 ... Thyristor
117 ... Zerocross control part
119 ... Mode controller
BEST MODES FOR CARRYING OUT THE INVENTION
The present invention will be explained specifically
with reference to Examples, but it should be understood that
the present invention is not limited thereto.
EXAMPLE 1
Testing apparatus 1 shown in Fig. 1 comprising acrylic
resin cylinder 4 was used. Twenty of northern house mosquitos
(female adult) were put in the space partitioned with insect
nets 2 and 2, and blower 3 was set at the bottom of testing
apparatus 1. Preparation-retaining material 5 comprising a
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honeycomb carrier impregnated with a preparation was fitted in
at the lower part of cylinder 4 and above blower 3. Air was
blown from the bottom of cylinder 4 and passed through the
preparation-retaining material 5 to release the pesticidal
component from the preparation, and the insecticidal effect was
examined using apparatus 1 for insect control of the present
invention.
The number of knockdowns of the mosquitos was counted
for every 30 seconds during 10 minutes and 30 seconds following
the start of the testing. The mosquitos knocked down were
transferred to a clean plastic cup (volume: about 500 ml)
containing a cotton wad impreqnated with a 1% aqueous sugar
solution as feed, and the cup was covered and maintained under
constant temperature conditions of about 25 C. The mortality
after 24 hours was observed. The results obtained are shown in
Table 2 below.
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TABLE 2
Results of Insecticidal Test
Examples Example
teralle- prall- fura- es- res- empen-
thrin thrin methrin biol methrin thrin
Number of 17 22 19 22 19 25
Insects*
Time
(min):
0.5 0 0 0 0 0 0
1.0 0 0 0 0 0 0
1.5 4 1 0 1 0 1
2.0 15 10 1 3 0 2
2.5 17 15 3 10 2 5
3.0 21 8 17 2 10
3.5 22 18 19 4 16
4.0 19 22 5 25
4.5 5
5.0 7
5.5 7
6.0 8
6.5 10
7.0 12
7.5 13
8.0 16
8.5 17
9.0 19
9.5
10.0
10.5 .
Mortality
24 hrs. 88 86 100 70 58 96
48 hrs. 100 100 100 78 79 100
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Notes Test insect:
Northern house mosquito (female adult)
Test Conditions:
Temperatures 26 to 30 C
Honeycomb carrier: 70 x 70 x 15 mm
Amount of the preparations 500 mg
The preparation-retaining material used herein was
prepared as follows. A honeycomb structure (70 x 70 x 15 M)
comprising a laminate of corrugated boards (single-aided) made
of bleached kraft paper having a basi.e weight of 80 glm2
(height of the corrugation: about 2 mm) was uniformly
impregnated with 3 ml of an acetone solution containing about
500 mg of preparation. The impregnated carrier was sot in the
apparatue after acetone vapori.sed.
The pesticidal components tested were teral],othrin,
empenthrin, prallethrin, furamethrin, esbiol, and resmethrin.
The vapor pressure of the tested pesticidal components
at 30 C on the cox diagram are shown in Table 3 below,
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TABLE 3
Vapor Pressure
Proparation , at 30 C
(mmHg)
empenthrin 1.5x10--'
terallethrin 6.6x10'4
prallethrin 1.3x10''
furamethrin 4.5x10'4
sobiol 1.2x10''
resmethrin 1. 7 x10'5
Test Results#
As is apparent from Table 2, the tested pesticidal
components, while having a vapor pressure a$ low as from
1x10--' wag to lxl0'I mmHq, achieve a lethal activity of 100 to
80% when applied to the method of the present invention
comprising applying an air current to the preparation-retaininq
material, exhibiting an extremely excellent control effect on
insect pests.
aXAMPLS 2
A test on insecticidal effect on common mosquitos was
carried out using the system for determining airborne
concentrations shown in Fig. 6(spatial capacitys 24 m').
A fan type insect p st control apparatus having the
structure shoan in Pig. 2 and having fitted thereto a honeycomb
carrier (70 x 70 x 15 mm) impregnated with 4.5 g of empenthrin
was put at the prescribed position of the system. For
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comparison, a commercially available liquid type electric
mosquito control apparatus using prallethrin was used.
Two cages each containing 20 to 25 of northern house
mosquitos (female adult) were set 150 cm or 75 cm high from the
floor. The apparatus was operated for 2 hours. A tester
entered the room for every 10 minutes and counted the number of
knockdowns. After the test, the insects knocked down were put
in a plastic cup. Twenty-four hours later, the number of dead
insects was counted. The results obtained are shown in Table
4 below. It is seen that the fan type apparatus and liquid
type electric apparatus (prallethrin) are equal in knockdown
effect in terms of KT50 and that the former is superior to the
latter in lethal effect.
TABLE 4
Mortality after
KTso (min ) 24 Hours (%)
Height from Floor Height from Floor
150 cm 75 cm Average 150 cm 75 cm Average
Fan type 69 69 64 51 59 55
Liquid type 102 82 92 11 15 13
EXAMPLE 3
A test was carried out in a test room having a spatial
volume of 24 m' under the following conditions, and the
knockdown ratio (after 24 hours) and the mortality (%) in
cockroaches were examined.
The insect pest control apparatus of the present
invention was put at the center of the floor of the room, and
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two cups each containing 20 cockroaches were placed at each of
the two opposite corners of the f loor . The pesticidal
component shown in Table 5 below was released from the
apparatus for consecutive 24 hours. As test insects, sensitive
German cockroaches (Blatel2a germantcs) and sensitive
amokybrown cockroaches (Fer.iplaneta fuliginosa) were used.
The preparation-retaining material used was prepared by
impregnating a honeycomb carrier (70 x 70 x 15 mm; Pig. 3) with
1.0 g of the posticidal component.
The results obtained are shown in Table 5.
TABLE 5
Pestiqidal CQUonerit
Benfluthrin Empen h.in
German Smokybrwm German Smokybrown
Cockroach Cockroach Cockroach Cockroach
Knockdmtn (Senni- (Sensi- (3ensi- (Bansi-
Rat g (t)~ tiy.ity) tiyit vL_ tivitv 1 tivitv1
l hr 0 0 0 0
3 hYS 0 0 0 0
4 hrs 0 5.0 0 0
24 hr8 87.5 6.3 90.0 65.0
Mortality at 97.5 7.5 90.0 75.0
48 hrs (+1)
SxAMPLB 4
Formulations for Honeycomb Impregnations
No. 11
empenthrin 4.0 q
N-benzoylvaline 0.05
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ethanol 0.50 g
Irganox 1010 (Ciba-Geigy Corporation) 0.1 g
tetrakis(m thylene-3-(3,5-di-t-butyl-
~-hydroxyphenyl)propionate)
The above composition was infiltrated into a honeycomb
carrier of 66 x 66 x 15 M.
No. Z
empenthrin 1.0 g
20Z'-methylenebis(4-methyl-6-t- 0.15 q
butylph nol)
piperonyl butoxide 1.5 g
The above composition was infiltrated in a honeycomb
carrier of 50 x 50 x 15 mm.
No. 3:
benf luthrin 0.5 g
bisphenol A 0.02 q
isostearyl palmitate 0.05 q
The above composition was infiltrated in a honeycomb
carrier of 35 x 35 x 10 mm.
No. 4:
b nfluthrin 2.0 g
N-hexanoyl-e-aminocaproic acid 0.03 g
ieopropyl myriatate 0.15 q
The above composition was infiltrated in a honeycomb
carrier of 70 x 35 x 15 mm.
No. 51
allothrin 1.5 g
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S-421 1.5 q
2,6-di-t-butylhydroxytoluene 0.2 g
The above compoeition was inf"iltrated in a honeycomb
carrier of 50 x 50 x 20 mnn.
No. 4s
tetramethrin 1.3 g
4,41-bntylidene-bis(3-methyl-6-t- 0.01 q
butylphenol,)
The above compoaition v-as infiltrated in a honeycomb
carrier of 50 x 50 x 10 mm.
No. 5e
prallethrin 0.5 q
2-hytiroxy-4-n-octyibensophenone 0.2 g
The above compoeition Kas infiltrated in a honeycomb
carrier of 30 x 30 x 20 nmm.
ExuMPLB 5
Formulations for 8olutione:
No. 61
empenthrin 5.0 g
2,6-di-t-butylhydroxytoluene 0.6 g
perfume 0.1 q
kerosine 35 ml
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No. 7:
prallethrin 1.3 g
2,6-di-t-butylhydroxytoluene 0.1 q
perfume 0.1 g
kerosine 40 ml
ERAMPLE 6
Water-based Formulations:
No. $_
empenthrin 2.0 q
butyl carbitol 25 ml
propylene qlycol 17 ml
water 8 ml
butylhydroxytoluene 0.20 q
INDUSTRIAL APPLICAHILITY
Currently available insect pest control methods and
apparatus uainq effective pesticidal components are of the type
that the active ingredient of a pesticidal preparation is
vaporized and diffused under heating conditione. However, the
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methods and apparatus used under heating conditions are
accompanied by an increase in temperature of the equipment or
surrounding temperature, involving a danger of a burn.
On the other hand, known insect pest control means
using preparations which are effective under non-heating
conditions, such as DDVP, involves a safety problem.
Preparations which are known to be effective in insect
pest control but are not considered to be released in a
concentration sufficient for insect pest control under non-
heating conditions only by blowing have been studied
systematically by analyzing the vapor pressure vs. temperature
relationship plotted on a cox_diagram. As a result, it has
been found that an extremely excellent pesticidal effect can be
obtained simply by blowing air under non-heating conditions by
using a safe and yet effective pesticidal component which is
hard to vaporize at normal temperature, preferably a component
having a vapor pressure of higher than 1x10'' mmHg at 30 C,
still preferably a component having a vapor pressure of higher
than 1x10'7 mmHg and a boiling point of not lower than
120 C11 mmHg.
Therefore, the present invention makes it feasible to
develop a method and an apparatus for controlling insect pests
which are simpler and safer than the conventional ones.
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