THE FIELD OF THE ART
[0001] The invention relates to the antimicrobial and/or anti-rodent protection provided
in plastic pipes and accessories employed in covering power supply lines in installations
of electrical distribution networks exposed to the ambient environment.
THE BACKGROUND OF THE INVENTION
[0002] An electric power distribution network within a residence, an industrial or a commercial
environment comprises appropriately arranged power supply lines providing power for
a variety of uses at a plurality of locations within the building, such locations
having been determined during the stage of designing the functioning of the building.
A thermoplastic composition incorporating an antimicrobial additive in association
with compatible physical property modifying agents, such as plasticizers, stabilizers,
flame retardants and the like has been employed in various circumstances in association
with such electrical power supply installations with a scope of offering protection
against attack from a variety of biologically destructive sources, such as fungal
growth and microbial attack, thereby diminishing fungal and microbial growth in the
surroundings. Antimicrobial additives have been commonly employed in a variety of
applications, such as in the production of sanitary articles, of dyes, etc. Such antimicrobial
protection is deemed absolutely necessary in hygienically sensitive environments,
such as in workshops processing food or pharmaceutical products or in hospital and
clinic facilities or in crowded environments, such as schools, sport and recreation
centers, restaurants, etc. Reference is made to the following patents of the prior
art that describe use of an antimicrobial additive in connection to cables and cords
employed in electrical installations.
[0003] US 2009/0101387 discloses a multiple conductor electrical cord, the cord being insulated within a
jacket being manufactured with a thermoplastic composition that contains an agent
inhibiting biological contamination. This invention is related in particular to wire
or cable having at least two conductive electrical wires (core) and having a sheath
on this core comprising at least one thermoplastic polymer layer which contains the
antimicrobial properties.
[0004] EP 0749128 discloses a filling compound for use in cables and spliced cable connectors, particularly
applicable in the field of telecommunication industry, wherein the filling compound
comprises amongst other materials an anti-fungal and anti-corrosive ingredient.
[0005] EP 0417713 discloses an electric cable having an outer sheath based on a polymer mixture containing
a repellant and insecticide with a scope of providing protection to the cable from
the attack of insects, viz-z-viz termites.
[0006] WO 2006/016899 discloses an NBC resistant composition for use in hazardous environments containing
nuclear, biological or chemical agents, the composition comprising a terpolymer of
an ethylene-propylene-diene monomer (EPDM), a flame retardant and an antimicrobial
agent, that may be applied in cables.
[0007] A typical electricity distribution network including such in a hygienically sensitive
environment, as is the case with a food or a pharmaceutical industry, comprises a
variety of power supply conductors that have different dimensions, especially in relation
to the number and thickness of the wires employed in each particular case to serve
by way of example lighting requirements or motive requirements of operating machinery
and further they may include low voltage conductors, such as those employed in the
distribution of lines of telephony or of audio and/or visual signal reception lines.
Thus a variety of conductors is being employed, each having the necessary length in
order to pass from the predetermined locations wherein terminal power supply points
are required, these conductors being fastened to form a bundle of wires and guided
along predetermined paths to implement the electrical distribution network, each conductor
following a path according to the design and predetermined requirements pertaining
to the same, such path varying in length and in the number and location of intermediate
terminal points from the path followed by other conductors.
[0008] The object of the invention is to provide protection from microbial growth and/or
rodent attack in the overall electrical distribution network in hygienically sensitive
facilities, such as in industries processing food or pharmaceutical products including
storage facilities for such products, or in clinics and hospitals, etc. Taking into
consideration that in most electrical installations in such industrial, commercial
or clinic facilities the electrical distribution network is exposed to ambient conditions
and is not embedded within the wall structure of the building as is the case with
electrical installations in a domestic environment, the conductors are enclosed within
appropriately sized and formed conduits and a plurality of supplementary items, such
as bends, clips, couplers, spouts, adaptors and junction boxes being employed to implement
an integrated electrical distribution network.
[0009] The requirement of varying conductor specification and varying lengths of the plurality
of conductors employed to implement an electrical installation exposed to ambient
conditions as mentioned herein above, as well as the variety of intermediate terminal
points and paths followed by each one of the conductors renders the application of
the cited patents of the prior art inapplicable in solving anti-contaminant problems
in the case of the present invention, since such patents mainly concentrate in providing
a specific antimicrobial protection to a specific single or a multiple conductor cable
and cannot solve the problem of offering a substantial, economically viable, antimicrobial
protection in the case of electrical installations employing a variety of cables with
varying scopes and specifications, varying terminal points and varying lengths. Furthermore
the prior art does not provide for anti-rodent protection that, under certain circumstances,
e.g. in underground conduits of cables or in facilities that are left unattended for
long periods, such as may happen in storage facilities, may become a priority hazard
or even the sole hazard that needs to be tackled. Further, since such exposed electrical
installations are being covered with the aforementioned appropriately sized and formed
conduits and the aforementioned plurality of supplementary items, such as bends, clips,
couplers, spouts, adaptors and junction boxes employed to implement the electrical
distribution network, it is often awkward or even impossible to appropriately clean
and maintain such a complex structure in a condition that will inhibit microbial growth
and further act as a repellant of possible rodent attack.
[0010] Thus, the object of the invention is to provide an integrated system of conduits
and associated supplementary items, such as bends, clips, couplers, spouts, adaptors
and junction boxes employed to thoroughly cover the variety of power supply cables
in electrical installations exposed to ambient conditions, such integrated system
of conduits and associated supplementary items acting so as to eliminate microbial
growth and/or rodent attack thereby adequately protecting electrical conductor cables
being guided therein and advantageously diminishing microbial growth in the surrounding
environment, this integrated system comprising rigid and pliable conduits covering
the power supply conductors all along the length of the same, as well as bends, clips,
couplers, spouts, adaptors and watertight junction boxes provided at predetermined
designed locations along the lengths of such rigid or pliable conduits with a scope
of connecting and fixedly supporting sequential lengths of the abovementioned rigid
and pliable conduits, including underground conduits used to transfer electric power
and/or telecommunication cables to the site of the electrical installation, wherein
manufacturing of the aforementioned conduits and associated items is made with a thermoplastic
material that comprises a mixture of about 1-8% of an anti-microbial additive and
of about 1-8% of an anti-rodent additive.
[0011] It is expected that as long as the entire surface of the electrical installation
being exposed to ambient conditions is made with such a thermoplastic material that
comprises an anti-microbial and an anti-rodent additive, the entire system comprising
the rigid or pliable conduits and the supplementary connecting and supporting items,
as well as the cables being guided within such conduits are safely protected from
either microbial growth or rodent attack and thereby advantageously prevent microbial
growth in the surrounding environment.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] The invention will be made apparent to those skilled in the art by reference to the
accompanying drawings in which:
Fig. 1 shows a typical rigid linear conduit portion employed in the system of antimicrobial
and anti-rodent protective plastic items for coverage of conductor cables in an electrical
distribution network in accordance to the invention.
Fig. 2 shows a typical pliable conduit portion employed in the system of antimicrobial
and anti-rodent protective plastic items of the invention.
Fig. 3 shows a typical coupler item employed in the system of antimicrobial and anti-rodent
protective plastic items of the invention.
Fig. 4 shows a typical bend portion employed in the system of antimicrobial and anti-rodent
protective plastic items of the invention.
Fig. 5 shows a typical spout adaptor item employed in the system of antimicrobial
and anti-rodent protective plastic items of the invention.
Fig. 6 shows a typical junction box item employed in the system of antimicrobial and
anti-rodent protective plastic items of the invention.
Fig. 7 shows a typical clip item employed in the system of antimicrobial and anti-rodent
protective plastic items of the invention.
Fig. 8 shows an illustrative view of a portion of an electrical distribution network
wherein have been illustratively employed the antimicrobial and anti-rodent protective
plastic items of the invention.
Fig. 9 shows an illustrative view of a portion of an underground double-wall structured
conduit with antimicrobial and anti-rodent protection.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0013] The integrated system of antimicrobial and anti-rodent protective plastic items of
the invention comprises all necessary items for providing a full coverage of the cables
in a typical electrical installation that is not inbuilt in the wall and is exposed
to ambient conditions, namely the following items used in accordance to the designed
functioning of the electrical installation:
the appropriate lengths of rigid linear conduit portions 11 and lengths of pliable
conduit portions 12 being depicted in Fig. 1 and Fig. 2 respectively;
a plurality of couplers 13 adapted to connect linearly oriented sequential lengths
of the abovementioned rigid linear conduit portions 11 and/or lengths of pliable conduit
portions 12 (Fig. 3);
a plurality of bends 14 adapted to connect perpendicularly oriented sequential lengths
of the abovementioned rigid linear conduit portions 11 and/or lengths of pliable conduit
portions 12 (Fig. 4);
a plurality of junction boxes 16 covered with appropriately configured cover plates
16a (Fig. 6) and provided with a plurality of outlets arranged at the lateral sides
thereof, these outlets being provisionally covered with plug-in seals 16b and adapted
to receive spout adaptor members 15 in selected ones of these outlets after removal
of the plug-in seals 16b;
a plurality of spout adaptor members 15 (Fig. 5), each with an end 15b adapted to
fit within one of the abovementioned outlets of junction boxes 16 after removal of
the corresponding provisionally provided plug-in seal 16b and an end 15a adapted to
receive an appropriate length of a rigid linear conduit portion 11 or an appropriate
length of a pliable conduit portion 12, and
a plurality of clips 17 (Fig. 7) adapted to support the abovementioned lengths of
rigid linear conduit portions 11 and lengths of pliable conduit portions 12 and fixedly
mount the same onto a surface whereupon the electrical distribution network is being
installed. According to an illustrative embodiment of the invention, the abovementioned
clips 17 are appropriately sequentially spaced at distances of the order of 50 cm
for vertically oriented conduit portions and of the order of 40 cm for horizontally
oriented conduit portions.
[0014] As illustratively shown in Fig. 8, the necessary number of each one of the abovementioned
items is being employed to accomplish a specifically designed electrical distribution
network.
[0015] Fig. 9 illustratively shows two portions of a special make of an underground conduit
19 intermediately connected by means of a coupler 18, such underground conduits being
employed to transfer electric power or telecommunication signals with cables being
guided therein at the site of the electrical distribution network and being manufactured
in a co-extrusion process with a double wall structure with a corrugated exterior
wall surface and an inner smooth wall surface, either in the depicted pliable mode
of conduits following desired curved paths or in a rigid mode of conduits extending
in a linear direction.
[0016] To provide the desired antimicrobial protection of an electrical distribution network
all the abovementioned items are made from a thermoplastic material that advantageously
contains an anti-microbial additive at a percentage by weight of about 1-8%. In order
to provide a further anti-rodent capacity, the thermoplastic material contains an
anti-rodent additive at a percentage by weight of about 1-8% as well. In accordance
with a preferred embodiment of the invention the thermoplastic material advantageously
contains both an antimicrobial additive and an anti-rodent additive, each at a percentage
by weight of about 1-8% and when both additives being used the added percentages by
weight of the two constituent additives will not exceed 8%.
[0017] In accordance with a preferred embodiment of the invention the antimicrobial additive
can be selected to be silver ion commercially available by Biocote Ltd, whilst the
anti-rodent additive is a non-hazardous and non-toxic animal and bird repellent and
can be selected to be based on a quaternary ammonium adduct of Benzyl diethyl [(2,6-Xylylcarbamolyl
Methyl)] Ammonium Benzoate, N-[(4-hydroxy-3-methoxyphenyl)methyl]-8-methyl-, (E)-;
8-Methyl-N-vanillyl-6- and capsaicin derivatives.
EXAMPLE I
[0018] The thermoplastic raw material comprising an antimicrobial additive has an illustrative
composition of 96% HDPE (High density polyethylene), 2% master batch pigment and 2%
master batch of the anti-microbial additive.
EXAMPLE II
[0019] The thermoplastic raw material comprising an anti-rodent additive has an illustrative
composition of 96% HDPE (High density polyethylene), 2% master batch pigment and 2%
master batch of the anti-rodent additive.
EXAMPLE III
[0020] The thermoplastic raw material comprising an antimicrobial and an anti-rodent additive
has an illustrative composition of 94% HDPE (High density polyethylene), 2% master
batch pigment, 2% master batch of the anti-rodent additive and 2% master batch of
the anti-microbial additive.
[0021] The thermoplastic raw material can be selected from the group comprising polyethylene
(PE), high density polyethylene (HDPE), polypropylene (PP), polyvinylchloride (PVC),
polycarbonate (PC), polycarbonate / Acrylonitrile Butadiene Styrene (PC/ABS).
[0022] The various constituent parts of the integrated system of antimicrobial protective
plastic items of the invention are made in a variety of sizes and dimensions of each
part to fit applications of varying requirements.
[0023] Specimens of the various items of the integrated system of antimicrobial protective
plastic items of the invention have been tested in accordance with the method of "Determination
of Antibacterial Activity using Test Based on ISO 22196:2011 (Measurement of antibacterial
activity on plastic surfaces). The specific specimens were made by a thermoplastic
material with a composition including an antimicrobial additive containing the drastic
substance Silver Ion commercially available by BioCote Ltd. In particular the specimens
included:
rigid conduits, corrugated conduits and bends made from PVC with a composition that
contained 2% by weight of the antimicrobial additive,
rigid conduits, corrugated conduits and bends made from PC with a composition that
contained 3% by weight of the antimicrobial additive,
couplers made from HDPE with a composition that contained 3,5% by weight of the antimicrobial
additive,
clips made from PC/ABS with a composition that contained 3% by weight of the antimicrobial
additive,
junction boxes made from PC with a composition that contained 3% by weight of the
antimicrobial additive,
cover plates for junction boxes made from PE with a composition that contained 3%
by weight of the antimicrobial additive, and
adaptor members made from HDPE with a composition that contained 3% by weight of the
antimicrobial additive.
[0024] The tests were carried out with a scope of establishing the
antibacterial activity, i.e. the difference in the logarithm of the viable cell count found on an antibacterial-treated
product and an untreated product after inoculation with and incubation of bacteria
and the
antibacterial effectiveness, i.e. the ability of an antibacterial agent to inhibit the growth of bacteria on the
surface of a plastic treated with the agent, as determined by the value of the antibacterial
activity.
[0025] The tests provided data showing the difference in the population of the specific
bacteria (E Coli) and of the specific bacteria MRSA after contact thereof with the
surface of the samples for 24 hours at 35°C under RH of 95% relative to the initial
population of bacteria.
[0026] The data exhibited results as listed in the Certificate of Efficacy provided by the
certified agency BioCote Ltd for the various constituent parts of the integrated system
of antimicrobial protective plastic items of the invention that have been tested and
these results presented a relative reduction in the population of the bacteria being
tested (difference in the population following contact with the surface of the samples
listed for 24 hours at 35°C under RH of 95% relative to initial population) that exceeded
percentages ranging from 99.49-99.94% in the measurements made in relation to the
bacteria E.coli and percentages from 99.38-99.93% in the measurements made in relation
to the bacteria MRSA (staphylococcus). The integrated system of antimicrobial protective
plastic items for electrical distribution networks of the invention has also been
found effective against other microbes, such as salmonella, Klebsiella pneumoniae,
Streptococci, Enterococci, Pseudomonas aeruginosa, Acinetobacter baumanii, Legionella,
Lactobacilli and Clostridium difficile.
1. An integrated system of conduits and associated supplementary items employed to thoroughly
cover a variety of cables in an electrical distribution network, comprising appropriate
lengths of rigid linear conduit portions (11) and lengths of pliable conduit portions
(12), clips (17) adapted to support said lengths of rigid linear conduit portions
(11) and lengths of pliable conduit portions (12) and fixedly mount the same onto
a surface whereupon said electrical distribution network is installed, couplers (13)
adapted to connect linearly oriented sequential lengths of said rigid linear conduit
portions (11) and/or lengths of said pliable conduit portions (12), bends (14) adapted
to connect perpendicularly oriented sequential lengths of said rigid linear conduit
portions (11) and/or lengths of said pliable conduit portions (12), junction boxes
(16) covered with appropriately configured cover plates (16a) and provided with a
plurality of outlets provisionally covered with plug-in seals (16b), spout adaptor
members (15) with an end (15b) adapted to fit within said outlets of said junction
boxes (16) following removal of the plug-in seals (16b) provisionally covering the
same and an end (15a) adapted to receive an appropriate length of a rigid linear conduit
portion (11) or an appropriate length of a pliable conduit portion (12) and double-wall
structured pliable or rigid underground conduits (19) with a corrugated exterior wall
and an inner smooth wall intermediately connected by means of couplers (18), said
underground conduits (19) being employed to transfer electric power or telecommunication
signals with cables being guided therein at the site of the electrical distribution
network, characterised in that said integrated system of conduits and associated supplementary items used in the
electrical distribution network including said double-wall structured pliable or rigid
underground conduits used to transfer electric power or telecommunication signals
with cables being guided therein at the site of electrical distribution network are
being manufactured with a thermoplastic material having a composition comprising an
anti-microbial additive at a percentage by weight of about 1-8% and/or an anti-rodent
additive at a percentage by weight of about 1-8%.
2. The integrated system of conduits and associated supplementary items employed to thoroughly
cover a variety of cables in an electrical distribution network including said double-wall
structured pliable or rigid underground conduits used to transfer electric power or
telecommunication signals with cables being guided therein at the site of electrical
distribution network according to claim 1, being manufactured with a thermoplastic
material having a composition comprising both an antimicrobial additive and an anti-rodent
additive, wherein the added percentages by weight of said antimicrobial additive and
said anti-rodent additive lies within a range that does not exceed 8%.
3. The integrated system of conduits and associated supplementary items employed to thoroughly
cover a variety of cables in an electrical distribution network including said double-wall
structured pliable or rigid underground conduits used to transfer electric power or
telecommunication signals with cables being guided therein at the site of electrical
distribution network according to claims 1 and 2, wherein the thermoplastic material
used in manufacturing said system of conduits and associated supplementary items of
the electrical distribution network and said underground conduits can be selected
from a group comprising polyethylene (PE), high density polyethylene (HDPE), polypropylene
(PP), polyvinylchloride (PVC), polycarbonate (PC), polycarbonate / Acrylonitrile Butadiene
Styrene (PC/ABS).