Note: Descriptions are shown in the official language in which they were submitted.
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Knitted Microfiber Cleaning Cloth
Field of the Invention
The present invention relates to a knitted microfiber cleaning cloth as well
as a
cleaning article and a cleaning pad comprising such a lcnitted microfiber
cleaning
cloth. The present invention also relates to a cleaning implement as well as a
kit
comprising such a knitted microfiber cleaning cloth. The present invention
also relates
to a method of cleaning a surface.
Background of the Invention
Microfiber cleaning cloths, i.e. cleaning cloths comprising microfibers (i.e.
a fiber
having a linear density of one (1) denier or less) are known in the art.
Microfiber
cleaning cloths are advantageous in that they typically exhibit good cleaning
efficiency, e.g. picking up dust or dirt particles as well as the removal of
oils, grease,
fingerprints and the like, without the application of chemical cleansing
agents.
Typically such cloths are either woven or knitted. Knitting is generally
preferred
because the resulting butted microber cleaning cloth is more elastic than a
microfiber
cleaning cloth prepared by weaving and the knitted microfiber cleaning cloth
is, thus,
2o easier to wring out during wet cleaning or wiping.
Although blown knitted microfiber cleaning cloths exhibit a number of
properties
desirable for wet cleaning, such cleaning cloths typically exhibit a
disadvantageously
high drag during wet cleaning. This is especially true, when wet cleaning with
such a
cleaning cloth attached to a flat-headed mop or cleaning support of a cleaning
implement, due to a corresponding large contact area between the wiping
surface and
the surface to be cleaned. It is to be appreciated that for the user, wet
cleaning or
mopping with a mop or a cleaning implement exhibiting lugh drag is
particularly
disadvantageous. For every push and pull movement the user makes with the mop
or
3o cleaning implement, the user must exert extra effort or force to overcome
the drag at
the contact area, and when the drag is high he must exert correspondingly more
effort
or force. Thus wet cleaning or mopping large surface areas with a mop or
cleaning
implement exhibiting high drag can quickly become exhausting for the user.
CC~~~r~~~-~Y~~"~~~,r~a, G~~~
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Summary of the Inyention
Thus, there is an ongoing need for knitted microfiber cleaning cloths, which
exhibit a
desirably low drag during wet cleaning, while maintaining good cleaning
efficiency.
It has been surprisingly found that very low drag together with good cleaning
efficiency can be realized by providing a microfiber cleaning cloth knitted
with a
pique knitting pattern, which provides a cloth having a waffle-patterned
structure, i.e.
a structure having elevated portions in a form of a geometrical pattern with
non-
l0 continuous depressions between said elevated portions.
Accordingly, the present invention provides a microfiber cleaiung cloth
knitted with a
pattern comprising a pique knitting pattern.
15 In the present invention, a pique knitting pattern is understood to be a
knitting pattern,
which yields a knitted cloth having, on at least one side of the knitted
cloth, a waffle-
patterned structure. The waffle-patterned structure may be based on any
suitable
geometrical pattern, preferably substantially honeycomb or round patterns,
substantially square or rectangular patterns, substantially diamond patterns,
2o substantially trapezoidal patterns or substantially triangular patterns.
The geometrical
pattern may be such that the depressions of the waffle-patterned structure are
aligned
or staggered.
Preferred pique knitting patterns include Lacoste, Honeycomb, French pique,
Swiss
25 pique, single pique and Ottoman-Honeycomb patterns, all of which are well
known in
the art. Among these patterns, Lacoste, Honeycomb and French pique patterns
are
more preferred, while Lacoste and Honeycomb patterns even more preferred, and
Lacoste pattern most preferred.
3o Also, it has been found that in order to realize desirably low drag, the
entire
microfiber cleaning cloth need not be knitted with one single pique knitting
pattern.
Therefore, preferred embodiments of the invention include the provision of a
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microfiber cleaning cloth knitted with a pattern comprising a pique knitting
pattern
and a second knitting pattern.
More particularly, it has been surprisingly found that advantageously low drag
and
high cleaning efficiency can be achieved by providing a microfiber cleaning
cloth
kutted with a mixed pattern of pique knitting pattern with a second knitting
pattern,
which is not a pique knitting pattern. Thus, more preferred embodiments of the
invention include the provision of a microfiber cleaning cloth knitted with a
pattern
comprising a pique knitting pattern and a second knitting pattern, wherein
said second
1 o knitting pattern is not a pique knitting pattern.
Due to their advantageous cleaning properties, microfiber cleaning cloths
according to
the invention can be used for cleaning or wiping in wet state or also in dry
or damp
state as desired. Thus, the present invention provides a method of cleaning a
surface
comprising wiping the surface with a microfiber cleaning cloth of the
invention.
Microfiber cleaning cloths of the invention can be advantageously used as part
of a
cleaning article, e.g. cleaning pads, cleaning implements and the like.
Accordingly an
additional aspect of the invention is the provision of a cleaning article
comprising a
microfiber cleaning cloth according to the invention.
An additional aspect of the present invention is a method for the manufacture
of a
microfiber cleaning cloth comprising the step: knitting a cloth with a pattern
comprising a pique knitting pattern using at least one microfiber-containing
yarn. In
preferred embodiments of the method the pattern comprises a pique knitting
pattern
and a second knitting pattern.
A further aspect of the invention is the provision of a cleaning pad
comprising a
wiping layer comprising a microfiber cleaning cloth according to the
invention. In
preferred embodiments, the cleaning pad further comprises a base layer
adjacent to
3o microfiber cleaning cloth layer. Because microfiber cleaning cloths
according to the
invention exhibit very desirable properties for wet cleaning, in preferred
embodiments
of the cleaning pad the base layer comprises an absorbent material, e.g. a
water
absorbent material, such as foamed polymers, sponges or the Like.
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Due to their advantageous properties the microfiber cleaning cloths and the
cleaning
pads according to the invention are particularly suitable for cleaning, e.g.
wet
cleaning, large surface areas, in particular in conjunction with a flat-headed
cleaning
support. Accordingly, an additional aspect of the present invention is the
provision of
a cleaning implement comprising: a cleaning support member, said cleaning
support
member having a substantially flat bottom surface; and a microfiber cleaning
cloth or
a cleaning pad according to the invention releasably attached to cleaning
support.
1o Another aspect of the present invention is the provision of a kit
comprising:
a cleaning support member, said cleaning support member having a
substantially flat bottom surface; and
a microfiber cleaning cloth or a cleaning pad according to the invention.
15 Embodiments in accordance with the invention as well as further advantages
will be
described in the following with reference to the following drawings.
Brief Description of the Drawings
Figures 1 a to f show diagrams illustrating preferred pique knitting patterns
for use in
2o microfiber cleaning cloths in accordance with the invention.
Figures 2a and b show diagrams illustrating preferred second knitting patterns
for use
in preferred embodiments of microfiber cleaning cloths in accordance with the
invention.
Figure 3 shows the surface structure of a preferred embodiment of a microfiber
25 cleaning cloth knitted with a Lacoste pattern.
Figure 4 shows the surface structure of a preferred embodiment of a microfber
cleaning cloth knitted With a Lacoste pattern and a second knitting pattern.
Figure 5 shows the surface structure of a knitted microfiber cleaning cloth
known in
the art.
30 Figures 6 to 9 are cross-sectional views of four different, preferred
embodiments of a
cleaning pad.
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Figures 10 and 11 show isometric views of a preferred embodiment of a cleaning
implement. In Figure 10, the embodiment is shown in a collapsed state, while
in
Figure 11, in an extended state.
Figure 12 shows an isometric view of the preferred embodiment shown in Figures
10
and 1 I provided with a handle.
Figure 13 represents a schematic view of an experimental setup used to measure
the
drag of a sample.
l0 Detailed Description
The details and embodiments of the present invention are best understood by
reference
to the drawings.
Microfiber cleanin cloth
15 Microfiber clearing cloths according to the invention are knitted with a
pattern
comprising a pique knitting pattern, preferably using a circular or flat bed
knitting
machine, more preferably circular rib machine, most preferably a circular rib
double
knit machine. A pique knitting pattern means a knitting pattern which yields a
knitted
cloth having, on at least one side of the knitted cloth, a waffle-patterned
structure.
20 Preferred pique knitting patterns include Lacoste, Honeycomb, French pique,
Swiss
pique, single pique and Ottoman-Honeycomb patterns, all of which are well
known in
the art. In Figures la to 1f, said preferred pique knitting patterns are
diagrammed,
illustrating the yarn path 30 as well as dial needles 101,102 and cylinder
needles
201,202 of the yarn feeds (1-4,1-6,1-8 or 1-12 as the case may be).
In Figure 1 a the Lacoste knitting pattern, a rib gating pattern, is
illustrated. The pattern
is based on an eight feed repeat as follows: Feed No. 1 knit all cylinder
needles
201,202 and tuclc odd dial needles 101; Feed No. 2 knit all dial needles
101,102; Feed
No. 3 lrnit all cylinder needles 201,202 and tuck odd dial needles 101; Feed
No. 4 knit
all dial needles 101,102; Feed No. 5 knit all cylinder needles 201,202 and
tuck even
dial needles 102; Feed No. 6 knit all dial needles 101,102; Feed No. 7 knit
all cylinder
needles 201,202 and tuck even dial needles 102; and Feed No. 8 knit all dial
needles
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6
101,102. The surface structure of a preferred embodiment of a microfiber
cleaning
cloth knitted with a Lacoste pattern is shown in Figure 3.
Figure 1b shows the Honeycomb knitting pattern. This pattern, a rib gating
pattern, is
a modified Lacoste lcnitting pattern and is also based on an eight feed
repeat. Feeds 1,
3 to 5, 7 and 8 are the same as the Lacoste knitting pattern, while Feed No. 2
includes
knitting even dial needles 102 and Feed No. 6 knitting odd dial needles 101.
In Figure 1 c, the French pique knitting pattern is illustrated. This pattern,
a rib gating
to pattern, is based on a four feed repeat as follows: Feed No. 1 knit even
dial needles
102; Feed No. 2 knit all cylinder needles 201, 202 and odd dial needles 101;
Feed No.
3 knit odd dial needles 101; Feed No. 4 knit all cylinder needles 201,202 and
knit
even dial needles 102.
The Swiss pique pattern, a rib gating pattern, is illustrated in Figure 1d.
This pattern is
based on a four feed repeat as follows: Feed No. 1 knit all cylinder needles
201, 202
and odd dial needles 101; Feed No. 2 knit even dial needles 102; Feed No. 3
knit all
cylinder needles 201,202 and knit even dial needles 102; and Feed No. 4 knit
odd dial
needles 101.
The single pique pattern, an interlock gating pattern, is illustrated in
Figure 1e. This
pattern is based on a six feed repeat as follows: Feeds No. 1 and No. 5 knit
even
cylinder needles 202 and even dial needles 102; Feeds No. 2 and No. 4 knit odd
cylinder needles 201 and odd dial needles 101; Feed No. 3 knit even cylinder
needles
202 and tuck even dial needles 102; and Feed No. 6 knit odd cylinder needles
201 and
tuck odd dial needles 101.
In Figure 1 f, the Ottoman-honeycomb pattern, an interlock gating pattern, is
illustrated. This pattern is based on a twelve feed repeat as follows: Feeds
No. 1 and
3o No. 3 knit even cylinder needles 202 and even dial needles 102; Feeds No.
2, No. 4,
No. 6, No. 8, No. 10 and No. 12 knit odd cylinder needles 201 and odd dial
needles
101; Feeds No. 5, No. 7, No. 9 and No. 11 knit even cylinder needles 202.
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A gauge greater than or equal to 18 needles per inch is typically used on the
knitting
machine, preferably in the range of 18 to 28 needles per inch, more preferably
20
needles per inch.
Preferably, the microfiber cleaning cloth is knitted with a pattern comprising
a pique
knitting pattern and a second knitting pattern. Preferably, the second
knitting pattern is
not a pique knitting pattern. Suitable patterns for the second knitting
pattern include
knitting patterns, which provide a cloth having either a flat or non-dimpled
structure.
Examples of preferred patterns for the second knitting pattern include Milano
Rib and
1 o Ponte di Roma pattern, both of which are well known in the art.
In Figure 2a, the Milano Rib pattern, a rib gating pattern, is illustrated.
This pattern is
based on a three feed repeat as follows: Feed No. 1 knit all cylinder needles
201,202
and all dial needles 101,102; Feed No. 2 knit all cylinder needles 201,202;
and Feed
No. 3 knit all dial needles 101,102.
The Ponte di Roma pattern, an interlock gating pattern, is illustrated in
Figure 2b. This
pattern is based on a four feed repeat as follows: Feed No. 1 knit odd
cylinder needles
201 and odd dial needles 101; Feed No. 2 knit even cylinder needles 202 and
even dial
needles 102; Feed No. 3 knit all cylinder needles 201,202; and Feed No. 4 knit
all dial
needles 101,102.
For mixed patterns comprising a pique knitting pattern and a second knitting
pattern,
any suitable pattern sequence is useful. However, preferred pattern sequences
include
the following: two consecutive repeats of the pique knitting pattern followed
by two
consecutive repeats of the second knitting pattern; two consecutive repeats of
the
pique knitting pattern followed by one repeat of the second knitting pattern,
or one
repeat of the pique knitting pattern followed by two consecutive repeats of
the second
knitting pattern. A pattern sequence of one repeat of the pique knitting
pattern
followed by two consecutive repeats of the second knitting pattern is more
preferred.
The microfiber cleaning cloths are knitted with at least one microfiber-
containing
yarn. Other yarns, such as ground yarns, i.e. yarns, which do not comprise
microfibers
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and often provide structural support for microfiber-containing yarns, may also
be used
in the manufacture of the microfiber cleaning cloths. Preferably, the
microfiber
cleaning cloths are knitted from microfiber-containing yarn and ground yarn.
For
example, for a microfiber cleaning cloth knitted with a pattern comprising
Lacoste
knitting pattern, it is preferred that microfiber-containing yarns are applied
in feed
numbers l, 4, 5 and ~, while ground yarns are applied in feed numbers 2, 3, 6
and 7 of
the Lacoste pattern.
It will be appreciated that the microfiber-containing yarn is comprised of
fibers
to wherein each such fiber is a collection of distinct microfibers. The
microfibers are
preferably nylon and/or polyester microfibers, which typically render the
cleaning
cloth oleophilic as well as hydrophilic. Each yarn preferably comprises
between about
and 90% by weight nylon microfibers and between about 90 and 10% by weight
polyester microfibers, more preferably comprising about 70 to ~0% by weight
polyester microfibers and about 20 to 30% by weight nylon microfibers. The
microfibers in the individual fibers of the yarn can be observed (e.g.,
microscopically)
as alternating elongate layers or as wedge or pie shaped segments, for
example,
extending longitudinally along the lengths of the individual fibers. The
microfiber-
containing yarn may have a linear density between about 40 and 300 denier per
yarn,
preferably about 150 denier per yarn. "Linear density" or "fineness", in
referring to
yarns or to individual fibers, refers to the weight in grams of a 9,000 meter
length of
the fiber or yarn.
Ground yarn may comprise any of a variety of fibrous materials such as
polyester
(e.g., polyethylene terephthalate), nylon, rayon, cotton, and the like.
Because of cost,
commercial availability, and its ability to provide a web material that is
desirably soft,
the ground yarn preferably comprises polyester fibers, most preferably
polyethylene
terephthalate (PET) fibers. The ground yarn may have a linear density between
about
40 and 300 denier per yarn, preferably about 150 denier per yarn. Suitable
commercially available polyester yarns include those available from DuPont of
Wilmington, Delaware, comprising about 34 fibers per yarn with a linear
density of
about 150 denier per yarn.
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Water-soluble yarns may also be advantageously used in the knitting and/or the
manufacture of the microfiber cleaning cloth. Water-soluble yarn may include
such
yarns comprising polyvinyl alcohol ("PVA"), carboxy methyl cellulose thread,
carboxy ethyl cellulose thread, alginate fiber, and combinations of the
foregoing
materials. Yarns comprised of PVA are preferred and suitable PVA yarns will
have
linear densities within the range from about 1 to 300 denier per yarn and
typically will
comprise any number of threads and/or fibers per yarn as long as the yarn
remains
processable in the knitting process. Suitable commercially available PVA yarns
include a PVA yarn available from Nichibi KK of Japan having a linear density
of
to about 40 denier per yarn.
When a water-soluble yarn is used, the water-soluble yarn is preferably
dissolved out
of the knitted cloth during the manufacture of the microfiber cleaning cloth.
During
this process, the fiber structure of microfiber-containing yarn tends to
delaminate or
split so that the individual fiber structures, and the structures of the yarns
originally
made with those fibers, may no longer be observable within the cloth when
observed
under a microscope, for example. Instead of yarns of the original fibers, the
individual
microfibers may be seen arranged in distinct bundles woven into the cloth web
and
supported by the ground yarns. The bundles appear as a collection of
individual
2o microfibers arranged side by side and appearing substantially parallel to
and
conterminous with one another. Depending on the composition of the
microfibers, the
presence of bundles may render the microfiber web material hydrophilic as well
as
oleophilic. The microfiber cleaning cloths in accordance with the invention
preferably
comprise microfibers present in bundles. For such preferred microfiber
cleaning cloths
knitted from yarn comprising polyester and nylon microfibers, each bundle
preferably
comprises between about 10 and 90% by weight nylon and between about 90 and
10%
by weight polyester, and more preferably comprising about 70 to 80 % by weight
polyester and about 20 to 30 % by weight nylon.
3o For preferred embodiments of the microfiber cleaning cloth knitted with a
pattern
comprising a pique knitting pattern and a second knitting pattern, preferably
a water-
soluble yarn is used in the second knitting pattern during the manufacture of
the cloth.
Microfibers in the portions of the microfiber cleaning cloth knitted with the
second
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knitting pattern are preferably present in bundles. More preferably,
microfibers in the
portions of the microfiber cleaning cloth knitted with the second knitting
pattern are
present in bundles, while the portions of the microfiber cleaning cloth
knitted with the
pique knitting pattern are substantially free (more preferably free) of
microfibers in the
5 form of bundles. In such preferred embodiments, the portions of the
microfiber
cleaning cloth knitted with the pique knitting pattern may be free of
microfiber-
containing yarn. More desirably, for such preferred embodiments, the portions
of the
microfiber cleaning cloth lmitted with the pique knitting pattern comprise
microfiber-
containing yarn and the structure of the microfiber-containing yarn is
observable
to within said portions of the cloth when the cloth is examined under a
microscope.
A method for manufacturing a microfiber cleaning cloth according to the
invention
comprises the step of knitting a cloth with a pattern comprising a pique
knitting
pattern, preferably a pattern comprising a pique knitting pattern and a second
knitting
is pattern, using at least one microfiber-containing yarn. The manufacture of
a knitted
cloth preferably comprises first knitting a greige cloth which is formed with
a yarn
containing microfibers, preferably microfibers of polyester and nylon; a
ground yarn,
preferably a polyethylene terephthalate yarn; and, if desired, a water-soluble
yarn,
preferably comprising polyvinyl alcohol. "Greige cloth" refers to an
unfinished cloth
that, upon further processing, may be used as a microfiber cleaning cloth of
the
present invention. After the knitting step is completed, the greige cloth is
preferably
cleaned by the application of hot water (e.g., greater than 60°C,
preferably between 70
and 100°C) to remove dirt, oil, etc. picked up by the cloth during the
knitting step. In
the case that a water-soluble yarn was used in the knitting step, this yarn
will be
dissolved from greige cloth during the cleaning step. When a water-soluble
yarn is
used, it can be advantageous to perform the cleaning step twice. After the
cleaning
step, if desired, the cloth may be dyed. The cloth may then optionally be
stretched
and/or optionally be heat set (e.g. heating at temperatures within the range
from about
120°C to about 180°C typically for about 30 seconds or more,
preferably from about
3o 30 seconds to about 360 seconds). The thus prepared web may then be used as
a
microfiber cleaning cloth.
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11
The microfiber cleaning cloths according to the invention exhibit desirably
low drag
and good cleaning efficiency during wet or damp cleaning. The microfiber
cleaning
cloths also exhibit good cleaning efficiency for cleaning or wiping in the dry
state.
Thus, the microfiber cleaning cloths can be advantageously used alone for
wiping or
cleaning a surface, or they can be advantageously used as part of a cleaning
article,
such as a cleaning pad; a cleaning implement, e.g. a cleaning implement
disclosed in
commonly assigned co-pending EP application No. O110594~.2 filed March 9,
2001;
or the like.
l0 Cleanin~~ad
Cleaning pads according to the invention comprise a wiping layer comprising a
microfiber cleaning cloth according to the invention. The wiping layer is
typically the
portion of the cleaning pad that contacts the surface during cleaning.
15 As shown in Figure 6, the cleaning pad 40 preferably comprises two layers,
a wiping
layer 41 and a base layer 42 adj acent to the wiping layer. The base layer 42
may be
formed from any of a variety of materials capable of supporting the wiping
layer 41
and providing a means to grasp the cleaning pad during a cleaning application
(e.g"
dusting or wet wiping) or to attach the cleaning pad to a cleaning support.
Preferably
2o the base layer 42 comprises a material, which is also suitable for cleaning
operations,
so that the cleaning pad 40 is reversible and both the wiping layer 41 and the
base
layer 42 can each perform cleaning functions.
Suitable materials for the base layer 42 include absorbent materials, e.g.
water
25 absorbent materials; nonwoven materials, e.g. nonwoven webs of fibers;
fleece
materials and the other materials conventionally used in cleaning pads or for
cleaning.
Suitable absorbent materials include sponges, e.g. cellulose sponges; foamed
polymers, e.g. foamed polyurethane or polyester; and pile materials, such as
materials
comprising polymer, e.g. polyester, fibers having a length of about 1 cm on a
backing.
3o Suitable nonwoven materials include nonwoven webs of fibers, which are
useful for
scouring applications, are described in WO 97/49326. Among suitable nonwoven
web
materials, open, low density, three-dimensional, nonwoven web of fibers, the
fibers
bonded to one another at points of mutual contact, are preferred. Such
materials are
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12
described by Hoover et al. in U.S. Patent No. 2,95,593. Because the microfiber
cleaning cloth exhibits advantageous properties for wet cleaning, the base
layer 42
preferably comprises an absorbent material, more preferably a foamed polymer
or a
pile material. In preferred embodiments of the cleaning pad 40 in which the
base layer
42 comprises a pile material, it is preferred that the pile of the said
material faces
inwards towards the wiping layer.
Also as shown in Figure 7, the cleaning pad may be comprise a third layer 43,
which
is adjacent to the base layer 42. Suitable materials for the third layer 43
include a
to microfiber cleaning cloth according to the invention or other materials
suitable for
cleaning, such as those described for the base layer. In such preferred
embodiments of
the cleaning pad 40 comprising three layers, the base layer 42 preferably
comprises an
absorbent material and the third layer 43 comprises a nonwoven web of fibers.
Such
embodiments of the cleaning pad 40 are advantageously suited for dry, damp and
wet
15 cleaning as well as scouring with a single cleaning pad. For use with a
cleaning
support of a cleaning implement, the third layer 43 may comprise a material
suitable
for attaching the cleaning pad 40 to the support, such as loop material (e.g.
for use
with fastening hooks), polymer-based cloth and the like. Although not
preferred, the
base layer 42 may comprise two or more sub-layers.
The layers of the cleaning pad may be joined together in any conventional
manner
known in the art, e.g. by adhesive bonding, stitching or the like.
Alternatively, as
shown in Figure 8, the wiping layer 41 may be wrapped around the base layer 42
in a
continuous loop of material that is dimensioned to retain the base layer
within the loop
of material without adhesives. As illustrated in Figure 9, the wiping layer 41
may be
wrapped around the edges of the base layer 42 or any other layer 43 adj acent
to the
base layer 42, to provide a rolled edge 45, which may be held in place by
stitching
around the perimeter of the cleaning pad 40.
The cleaning pad 40 is preferably substantially rectangular or substantially
trapezoidal
in shape. Other shapes of cleaning pad 40 may be employed, round, elliptical,
triangular, as needed to accommodate a particular cleaning application or may
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13
otherwise be desired. Due to the advantageous properties of the microfiber
cleaning
cloths of the invention, discussed above and below, the cleaning pad is
particularly
advantageous for cleaning large surface areas, and for use with or attachment
onto a
cleaning support of a cleaning implement. Thus, it is preferred that the
cleaning pad
40 comprises a wiping surface having an axea greater than 110 cm2, more
preferably,
greater than 200 cmz, even more preferably greater than 300 cm2, most
preferably
greater than 400 cm2. Under the term "wiping surface" is understood the
exposed
surface of the cleaning pad for application onto a surface to be cleaned.
l0 Cleaning im lement
As illustrated by a preferred embodiment of the cleaning implement shown in
Figures
and 11, the cleaning implement in accordance with the invention 60 comprises a
cleaning support member 50 and a microfiber cleaning cloth or, preferably, a
cleaning
pad 40. The construction and the materials of the microfiber cleaning cloth or
the
cleaning pad are the same as the construction and the materials of the various
foregoing embodiments of the microfiber cleaning cloth or cleaning pad.
The cleaning implement 60 preferably further comprises a handle 70 which is
attached
to the cleaning support member 50, as shown in Figure 12.
The cleaning support member 50 and the handle 70 may be made of any suitable
rigid,
durable material, such as wood, metal, plastic or combinations of these
materials.
Plastic is preferred since it can be molded into a finished piece and thereby
may be
less expensive to manufacture. The length of the handle 70 will be dictated by
the end-
use of the implement, e.g. 1 to 2 meters for a cleaning floors and 2 to 3.5
meters for
cleaning walls, windows or ceilings. Preferably the handle 70 is a telescope
handle as
known in the art, whereby the length of the handle can be set as desired or
needed for
a particular cleaning application. The handle 70 is preferably removably
attached to
the cleaning support member 50. To facilitate ease of use, the cleaning
support
3o member 50 can be pivotably attached to the handle 70 using joint assemblies
known
in the art. The top surface 54 of the cleaning support member 50 typically
comprises a
central connection hub 55 to facilitate attachment of a handle 70.
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14
As shown in Figures 10 and 11, the cleaning support member 50 may be formed
from
two plates 51,52 with a hinged member 53 disposed between the two plates (i.e.
a
butterfly-type cleaning support member), which may facilitate the attachment
of the
cleaning pad 40 to the support member 50. Alternatively, the cleaning support
member 50 may be formed from a single plate. As shown in Figure 11, the
cleaning
support member 50 has a substantially flat bottom surface 56.
The bottom, i.e. plate or hinged plates, of the cleaning support member 50 is
preferably, substantially rectangular or substantially trapezoidal in shape.
For
l0 household purposes the cleaning support member 50 is preferably at least
about 6 cm
by 20 cm, more preferably at least about 7.5 cm by 27 cm, most preferably at
least
about 9 cm by 35 cm. For industrial cleaning purposes, a larger size for the
cleaning
support member 50 is preferred, more preferably at least about 12 cm by 40 cm,
even
more preferably at least about 14 cm by 50 cm, most preferably at least about
15 cm
15 by 60 cm. ~ther shapes and sizes of cleaning support member 50 may be
employed,
round, elliptical, triangular, as needed to accommodate a particular cleaning
application or may otherwise be desired.
For embodiments of the cleaning implement comprising a cleaning support member
20 50 and a cleaning pad 40, the cleaning pad preferably has a similar shape
as the
bottom of the cleaning support member. As shown in Figures 10 to 12, the
cleaning
pad 40 preferably extends a short distance in all directions beyond the
perimeter of the
bottom surface of the cleaning support member 50. The cleaning pad 40 can be
releasably attached to the cleaning support member 50 by any suitable means
known
25 in the art. For example, the cleaning pad 40 may be provided, on the side
opposite of
the wiping layer 41, with attachment pockets 46 or straps (not shown) made of
an
elastic material, which allow the releasable attachment of the cleaning pad to
the
cleaning support member 40. Alternatively, the bottom surface of the cleaning
support
member 50 may comprise fastening hooks which facilitate the releasable
attachment
30 of a cleaning pad 40. In this case, the outer layer of the cleaning pad
opposite of the
wiping layer 41 preferably comprises a material, such as a loop material,
which is
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directly, releasably attachable to the fastening hooks. Suitable fastening
hooks and
loop materials are well known in the art:
For embodiments of the cleaning implement comprising a cleaning support member
5 and a microfiber cleaning cloth of the invention, the cleaning support
member may
further comprise push-type fasteners on the top surface of the support or
other types of
fasteners, which facilitate the releasable attachment of a microfiber cleaning
cloth to
the cleaung support member. Alternatively, the microfiber cleaning cloth can
be
simply wrapped around the cleaning support member in a similar manner as a
1o conventional mop cloth.
The cleaning implement can be advantageously constructed from a kit comprising
a
cleaning support member and a microfiber cleaning cloth or a cleaning pad. The
kit
preferably further comprises a handle, which is attachable to the cleaning
support
15 member. The construction and the materials of the cleaning support member,
the
microfiber cleaning cloth or the cleaning pad as well as the handle for use in
a kit are
the same as the construction and the materials for the corresponding element
of the
various foregoing embodiments of the invention.
Test methods
Test method for determination of efficiency of fine dust pick-up
Efficiency of a cleaning cloth in picking up fine dust was determined by
measuring the
amount of fine dust taken up by the cleaning cloth in a dry state. In
particular, 0.400 g
of fine dust (grain size 125 micrometer and less) including walnut shells,
pumice,
aluminum oxide mineral, flint mineral and yellow iron pigment was spread over
three
by 30 cm ceramic tiles. After mounting the cleaning cloth (50 cm by 20 cm) on
a
flat-headed test support, the tiles were wiped with the cloth with a single
pass, i.e. one
forward and one backward stroke. The residual dust on the tiles was then
picked up
3o with a pre-weighed disposable microfiber cloth (typically having a weight
about 2 g).
The disposable cloth was then re-weighed to determine the weight of residual
dust.
The amount of dust picked up by the cleaning cloth was determined by
subtracting the
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16
weight of the residual dust from 0.400 g. Efficiency was then computed, i.e.
amount
of dust picked up by the sample in grams divided by 0.400 g and expressed in
percent.
Test method for determination of efficiency of oil removal
Efficiency of a cleaning cloth in oil removal was determined by comparing the
measured gloss value of a clean glass surface to the gloss value of same glass
surface
measured after soiling the surface with oil and wiping with the cloth. In
particular, the
60° gloss of a clean glass surface (30 cm by 30 cm) was measured using
a
reflectometer (commercially available under the trade designation MICRO-GLOSS
l0 60° Reflectometer from BYI~ Labotron Messtechnik AG,
Lausitzerstrasse 8, D-8192
Geretsried, Germany) at two positions: a first position, i.e. "position zero",
and a
second position 5 cm displaced along the surface from position zero, i.e.
"position
five". Subsequently one drop of oil (0.27g) was placed on the glass surface at
position
zero.
Samples, i.e. 5 cm by 7 cm, of the cleaning cloth to be tested were prepared.
A sample
was then mounted on a flat test support (5 cm by 7 cm in size, 580 g in
weight). The
sample was then (centrally) placed in contact with the oil drop at position
zero and
displaced 20 cm along the glass surface over position five and back to
position zero.
2o One such cycle of forward and backward displacement or wiping was defined
as a
pass. After 1, 3, 5, 10 and 15 passes, the 60° gloss was measured at
position zero and
position five. Efficiency was then computed for each position, i.e. gloss
value after
wiping divided by initial gloss value and expressed in percent. Gloss values
were
measured at position five to confirm that oil was actually removed by wiping
with the
sample, not simply distributed over the glass surface.
Oil removal was tested with samples of the cleaning cloth in the dry state as
well as in
the damp state. For testing in the damp state, before mounting the sample to
the test
support, the sample was dipped in water and the excess water was removed with
a
squeeze roller in order to obtain a constant level of water from one sample to
another.
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Test method for determination of drag
As illustrated in Figure 13, drag was measured by determining the force needed
to
drag a sample of the cleaning cloth 90 over a glass surface 91 at set speed
and
displacement using a Instron Dynamometer Model 1011(from Iustron SA, Parc
Ariane, F-78280 Guyancourt) 92 equipped with a traction system 93 using a
pulley 94
plus a load range cell of 0.50 kN 95 and equipped with a data processor 96.
H-shaped samples, i.e. 120 mm by 190 mm rectangles having 40 mm by 40 mm
exclusions centered on the two narrow sides, were prepared. A sample was
dipped in
water and the excess water was removed with a squeeze roller in order to
obtain a
constant level of water from one sample to another. The wet sample was then
mounted
on a flat test support 97 (made of polyacrylate); the dimensions of the bottom
of
support was 108 by 118 mm. The mounted sample was then weighed down using
weights) 98 to yield a total weight of 685 g for the sample and support. After
calibration of the load step with 5 kg and 1 kg weights and attachment of the
test
support to the traction system, the sample was then dragged over a
displacement of
150 mm at a crosshead speed of 400 mm/min. The force necessary to drag the
sample
was measured and computed in units of N. Each sample was measured twice and
the
results averaged.
Materials used
1. (Comparative) microfiber cleaning cloth, product available under the trade
designation "SCOTCH-BRITE High Performance Cloth" from Minnesota Mining and
Manufacturing Co., St. Paul, Minnesota, LTSA (referred to here as "HPW-
Material"),
- a cloth knitted with a non-pique pattern comprising yarn comprising
microfibers of
polyester and nylon (70 % polyester and 30% nylon) as well as ground yarn of
polyester; both yarns having a linear density of 150 denier. The microfibers
in the
cloth are arranged in bundles. The surface structure of the HPW-Material is
shown in
Figure 5; the bundles of microfibers are visible as tuft-like structures.
2. Microfiber cleaning cloth knitted with a Lacoste knitting pattern
comprising yarn
comprising microfibers of polyester and nylon (70 % polyester and 30% nylon)
as
well as ground yarn of polyester; both yarns having a linear density of 150
denier
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18
(referred to here as "Lacoste-Material"). In reference to the Lacoste knitting
pattern
illustrated in Figure la, the microfiber-containing yarns were used in Feed
Nos. 1, 4, 5
and 8 and ground yarns in Feed Nos. 2, 3, 6 and 7. The microfibers in the
cloth are
not arranged in bundles, i.e. the structure of the microfiber-containing yarn
is
observable within the cloth when the cloth is examined under a microscope. The
surface structure of the Lacoste-Material is shown in Figure 3.
3. Microfiber cleaning cloth knitted with a mixed pattern having a pattern
sequence of
one repeat of Lacoste knitting pattern (as described above for the Lacoste
Material)
1o followed by two consecutive repeats of a non-pique knitting pattern (i.e.
that used for
the HPW material). (This material is referred to here as "Mixed-Material".)
The
Mixed-Material comprises yarn comprising microfibers of polyester and nylon
(70
polyester and 30% nylon) as well as ground yarn of polyester; both yarns
having a
linear density of 150 denier. In the portions of the Mixed Material knitted
with the
15 second knitting pattern, the microfibers are arranged in bundles, while in
the portions
knitted with the Lacoste knitting pattern the microfibers are not arranged in
bundles.
The surface structure of the Mixed-Material is shown in Figure 4.
2o Test Results
Efficiency of fine dust pick-up:
For each cleaning cloth tested, three individual samples were tested as
described
above and the results for the amount of dust picked up by three samples
averaged.
Efficiency based on the averaged value for dust pick-up was calculated. The
results
25 are reported in the following Table.
Sample Dust Efficiency,
picked
up by
sample
(g)
Sample Sample Sample Average
1 2 3
HPW-Material 0.360 0.385 0.365 0.370 92.5
Lacoste-Material0.339 0.334 0.334 0.336 84.0
Mixed-Material0.347 0.342 0.381 0.357 89.3
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19
The results of fine dust pick-up testing show that the microfiber cleaning
cloth knitted
with the Lacoste pattern or the mixed pattern exhibits good or very good
efficiency in
dust piclc-up. The cleaning efficiency of the Mixed material is comparable to
that
observed for the HPW material.
Efficiency of oil removal
For each cleaning cloth, efficiency of oil removal was tested in both dry and
damp
state as described above. Efficiency of oil removal after the corresponding
passes was
computed as described above, and the results are reported in the following
Tables.
to
Sample tested PositionEfficiency
in (%) after
dry state given
number
ofpasses
1 ass 3 asses 5 passes 10 asses 15 passes
HPW-Material 0 76.54 90.83 95.52 96.91 97.23
5 76.95 90.07 93.28 96.16 96.58
Lacoste-Material0 81.02 81.02 80.17 78.90 79.74
5 84.98 78.27 78.81 77.95 79.95
Mixed-Material0 88.95 87.42 87.32 87.32 88.38
5 90.20 88.64 88.00 88.00 87.30
Sample tested PositioEfficiency
in n (%)
dam state after
given
number
of passes
1 pass 3 passes5 passes 10 passes15 passes
HPW-Material 0 84.97 86.56 87.09 88.57 87.83
5 85.44 86.72 86.29 84.38 87.61
Lacoste-Material0 84.14 86.05 86.05 87.42 87.74
S 82.94 85.17 85.17 85.91 85.50
Mixed-Material0 86.93 83.41 84.96 86.88 86.56
5 85.13 82.03 83.69 85.56 84.71
The results of testing show that the microfiber cleaning cloth knitted with
the Lacoste
i5 pattern or the mixed pattern exhibits good or very good efficiency in oil
removal in
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the dry state. In the damp state, the microfiber cleaning cloth knitted with
the Lacoste
pattern or the mixed pattern exhibits very good efficiency in oil removal,
comparable
to that of the HPW material.
Dra~LValue
Three series of measurements were performed, in each case determining the
force
needed to drag the sample of the cleaning cloth over the test surface as
described
above, with two different sets of samples. The results are reported in the
following
1 o Table:
Sample Drag value (I~
First Series Second Series Third Series
HPW-Material 3.24 3.28 3.32
Lacoste-Material1.10 1.19 1.19
Mixed-Material1.65 1.74 1.74
The results of testing show that the microfiber cleaning cloth knitted with
the Lacoste
pattern or the mixed pattern exhibits very low drag and that the observed drag
values
15 for these cloths are significantly lower than that of the HPW material.
The results of the drag measurements together with the results of the cleaning
efficiency tests show that the microfiber cleaning cloth knitted with the
Lacoste
pattern or the mixed pattern exhibits a significant lower drag in comparison
to a
2o conventional microfiber cleaning cloth, while maintaining good or
comparable
cleaning efficiency.
