Note: Descriptions are shown in the official language in which they were submitted.
CA 02472683 2004-06-29
PROTECTIVE DEVICE AGAINST BITING OF ARTHROPODS
FIELD OF THE INVENTION
The present invention relates to a new protective device for use against
biting of
mosquitoes and other arthropods and in particular, a material which can be
used in the
manufacture of regular clothing or specialty clothing to protect an individual
from bites
from mosquitoes and other arthropods.
BACKGROUND OF THE INVENTION
One of the most serious concerns of today's society is the transfer of disease
from
mosquitoes and other arthropods to humans. For example, every twelve seconds a
child
dies from malaria. Almost half a billion people contract the disease annually.
One of the
most common ways of contracting the disease is when a human is bitten by a
mosquito
which carries the tiny blood-dwelling parasites that cause :malaria.
Many efforts have been made to reduce the spread of malaria. For example,
mosquito larvae thrive in stagnant swamp water so draining of swamps deprives
malaria-
carrying mosquitoes of their reproductive environment. While drainage schemes
have
led to the eradication of malaria from most of Western Europe and the United
States, the
1
CA 02472683 2004-06-29
disease remains a serious concern in parts of the Far and Middle East and in
South
America and Africa where ninety percent of the world's cases are found.
Malaria is such a large concern that it contributes significantly to economic
malaise. The disease is transmitted by the bite of hungry i:emale mosquitoes
looking for
blood to nourish their eggs.
A second disease which is carried by mosquitoes is the "West Nile" virus which
inflames the brain. This disease has affected North America to a very large
extent in the
past few years and efforts have been taken to spray insecticides over large
areas to try to
reduce the mosquito population.
Lately, various products have been designed and are on sale to protect humans
from the bite of arthropods such as mosquitoes to prevent the transmission of
disease.
Various articles of clothing have been designed which are manufactured of mesh
material
which keeps out the small bugs including no-see-ums, black flies, mosquitoes
and ticks.
One such product is available from Wisemen Trading and Supply of Athens,
Alabama
under the trade mark BUG OUT and is manufactured of a one hundred percent
polyester
chemically resistant material. Other protective clothing is made of tightly
woven cloth
material which is too dense for mosquitoes to bite through. The major drawback
of this
method is that it becomes hot and sweaty in hot weather and is therefore
uncomfortable.
2
CA 02472683 2004-06-29
Various other attempts have been made to protect lhumans. Although vaccines or
chemoprophylactic drugs are available against vector-borne diseases such as
yellow fever
and malaria, suggestions have been made for general protf;ctive measures
against biting
arthropods. While chemoprophylaxis is available for malwia, there are no
similar
preventive measures for such other mosquito-borne diseases such as dengue.
Suggestions
have been made to modify patterns of activity or behaviou~~r to avoid certain
times of the
day such as the twilight periods at dawn and dusk or in thf; evening when
vector
mosquitoes are most active. It is also suggested that long sleeved shirts,
long pants and
hats be worn to minimize areas of exposed skin.
Various repellents are also available such as perme;thrin-based products which
enhance protection. These insecticides may be applied to clothing, shoes,
beds, camping
gear and the like.
A popular chemical found in many repellents contain N,N-diethylmetatoluamide
(DEET) as the active ingredient. It has been found that DIEET repels
mosquitoes, ticks
and other arthropods when applied to the skin or clothing, Various
formulations are
presently available on the market.
One concern is the safety of the use of DEET for children. The concentrations
must be reduced when applying DEET formulations to children which provide only
short
3
CA 02472683 2004-06-29
term protection. Also, DEET is toxic when ingested and may cause skin
irritation in
persons.
Other chemical products are being tested and evaluated as adjuvants against
several species of malaria causing plasmodium.
Significant disadvantages arise as a result of the us;e of chemical products,
including, the fact that the chemicals must be repeatedly applied as a result
of "wearing
off ' over time and as a result of human activity such as sweating, showering
or
swimming. Frequent application of chemical repellents is also expensive and
may harm
the environment.
It has been estimated that at least eighty percent of human infectious
diseases are
arthropod-borne and are transmitted by insects, mites or ticks. They have
caused the
death of hundreds of millions of people by infecting them with pathogens that
cause
typhus, bubonic plague, yellow fever, malaria, dengue fever, sleeping
sickness,
encephalitis, elephantiasis, Leishmaniasis and yaws. Of these, mosquitoes have
been the
worst of all the disease earners. More than three thousandl species of
mosquitoes have
been described in scientific journals and mosquitoes have 'been found in every
country of
the world.
4
CA 02472683 2004-06-29
From the viewpoint of the military, recent studies have shown that arthropods
can
obstruct movement and field positions, prevent concealment and cover and
disrupt
manoeuvres and cause panic. There is clearly a lost work time, treatment and
hospitalisation costs are increasing substantially.
One of the problems encountered with respect to the netting which is currently
available is that the netting all use a mesh which touches 'the skin of the
individual. The
problem is that when the arthropod lands on the mesh, it can bite through the
mesh itself
thereby transmitting the disease to the human notwithstanding that netting is
applied to
the body. Attempts to try to keep a safe distance between the netting and the
skin by
wide brimmed hats or hoops are impractical and often inei:fective. There is
also clearly a
problem in retaining visibility through the netting. The alternative to
netting is the use of
tightly woven material which does not allow the skin to breathe or to
dissipate
perspiration and is therefore very uncomfortable to use.
SUMMARY OF THE INVENTION
To at least partially overcome the disadvantages of the prior art, the present
invention provides a novel protective device for use to assist in the
prevention of the
biting of arthropods.
CA 02472683 2004-06-29
It is another object of the present invention to :provide a material from
which
articles of clothing may be made to assist in the prevention of biting of
arthropods.
To this end, in one of its aspects, the invention prcmides a reticulated foam
for use
as a component of an article of clothing.
In another of its aspects, the invention provides a reticulated foam for use a
component of an article of clothing to prevent an arthropod from biting
through the
article of clothing.
In yet another of its aspects, the invention provides a reticulated foam
having a
density of holes from about ten per linear inch to about one hundred per
linear inch for
use as a component as an article of clothing.
In a still further aspect of this invention, it provides a reticulated,
flexible
polyurethane foam characterized by a three dimensional skeletal structure of
strands for
use as a component of an article of clothing.
In a further aspect, the invention provides a material for use in the
manufacture
of clothing for the prevention of bites from arthropods which comprises a
reticulated
foam.
6
CA 02472683 2004-06-29
BRIEF DESCRIPTION OF THE DRAWINGS
Figure 1 is a perspective view of a head covering made of the reticulated foam
of
the present invention.
Figure 2 is a perspective view of a second embodiment of a head covering
incorporating the reticulated foam of the present invention.
Figure 3 is a front view of a pattern suitable for use in the manufacture of a
head
covering of the present invention.
Figure 4 shows the use of a head covering of the present invention on the head
of
a person.
Figure 5 shows the use of a head covering of the present invention on the head
of
a person in a second position.
DETAILED DESCRIPTION OF THE INVENTION
The protective device of the present application is made of a reticulated foam
having a density of holes from about ten per linear inch to about one hundred
per linear
inch with the preferred range being from about ten per linear inch to thirty
per linear inch.
7
CA 02472683 2004-06-29
The foam is preferably a reticulated, flexible polyurethane foam which is
characterized by a three-dimensional skeletal structure of strands which
provide a ninety-
seven percent void space. As indicated before, the controlled pore sizes run
from a
density of about ten per linear inch to about one hundred per linear inch
which therefore
guarantees uniformity and predictability. This material can be shaped and
coloured to
meet a broad range of requirements and generally flexible, resilient and
lightweight.
These materials exhibit controlled permeability .and predictable surface area
of
the skeletal structure which is a direct function of the totally open pore
cell size.
Confirmation to contact surface and shape retention is due to the resilient
nature of the
polyurethane foam which exhibits excellent holding capacity and low flow
resistance as a
result of the foam's high void volume.
The material is quite breathable and wicks perspiration away very quickly.
There
is no odour and the material exhibits low resistance to airflow. It is totally
washable and
susceptible to additional materials such as carbon to improve heat
conductability of the
material itself.
The particular advantage of using the reticulated foam is that it provides a
spacing
between the arthropod which many land on the device and the skin of the human.
The
arthropod when landing on the device cannot penetrate to the skin of the
wearer of the
device and thus the wearer is protected from bites from the arthropod.
8
,.,~x.,.<,_., >" ~ a.<.. < :...nz~:r w.;a~~z2~-~~s....~..~;~,.~..aa... .e
.._..,.--...._ ..........,........,.~ _,.,."o,.",~,.,""".~~....__.
______._..__..__. __.r _.
CA 02472683 2004-06-29
The reticulated foam may be incorporated into .any type of article of
clothing.
These may include head coverings, jackets, pants, socks, ~~nitts, overalls and
the like. The
present invention relates to the use of the reticulated foamy as a component
of an article of
clothing which can be used to cover all or a part of the body.
Referring to figure 1, there is representation of a lhead covering
incorporating the
invention of the present application. The head covering generally indicated as
2 is made
of reticulated foam material and is shaped to fit over the head of the user.
The head
covering is placed over the head and the head is pushedl through opening 4 so
that the
eyes of the user fit within the opening 6. A transparent shield 8 covers the
eyes of the
user.
An alternative version is shown in figure 2 wherein a flap 10 is moveable to
close
the opening 6 if desired.
Clothing may be manufactured of the reticulated foam itself. Alternatively,
the
reticulated foam can be worn on top of the clothing or under the clothing if
desired.
The foam has good flexibility and can therefore 1>e compressed into a pouch
for
easy carrying. Accordingly, it finds particular application for the armed
forces and also
for sports events, cyclists, hikers, cottagers and the like. The material is
breathable thus
9
CA 02472683 2004-06-29
preventing heat buildup. It also wicks perspiration away very quickly. The
material has
little or no odour and has a low resistance to airflow and is totally
washable.
If desired, additional material may be incorporated into the reticulated foam.
For
example, carbon may be incorporated into the reticulated foam to improve the
heat
conductability. Colouring may also be used for aesthetic 1?urposes.
EXPERIMENT 1
Refernng to figure 3, a pattern 22 was first made ~of a simple sheet of one-
quarter
inch thick reticulated foam having thirty holes per inch. A clear view visor
24 made of
thin Lexan (trade mark) was attached to the foam using a silicone glue to
cover the
opening 26. The helmet was then sewn along a single seam 28 to produce the
helmet as
shown in figures 4 and 5.
Figure 4 shows the helmet 30 with flaps 32, 34 outside of the shirt of the
wearer
36. Figure 5 shows the helmet 30 with flaps 32, 34 tucked inside the shirt of
the wearer
36. The wearer 36 then places the helmet 30 over his head and tucks the flaps
32, 34
inside of his shirt as shown in figure 5. After a recent: rainstorm, the
wearer walked
through a mosquito infested forest for two hours. Following the two hour walk,
the
wearer removed the helmet 30 for inspection and then inspected his body for
mosquito
bites.
CA 02472683 2004-06-29
It was found that the wearer suffered numerous mosquito bites to all areas of
his
body which were covered with normal clothing but not a single bite was located
on the
head or on the face of the wearer.
The wearer also reported no problem with respect to ease of breathing,
comfort,
hearing or visibility. The experiment was repeated with the wearer wearing
eyeglasses
and there was no discomfort felt by the wearer when the wearer wore
eyeglasses.
Although it is acknowledged that this field test was arbitrary, it was clear
that the
results showed that the mosquitoes could not bite through the helmet made of
the
reticulated foam of the present invention and this helmet allowed the wearer
to walk
through mosquito-infested areas without being bitten.
While the invention has been described with respect to the preferred
embodiments, many modifications and variations will novv occur to persons
skilled in the
art. F'or a definition of the invention, reference is made to the appended
claims.
11
