Note: Descriptions are shown in the official language in which they were submitted.
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,
EMBOSSED DUST MOP HAVING EMBOSSED,
NONWOVEN FABRIC CLEANING ELEMENT
Dust removal from smooth hard surfaces such as
floors is a continuing problem both for the homemaker and
for professional building maintenance personnel. Such
removal is generally accomplished by wiping the surface
with a cleaning element such as a fabric which may be held
in a frame. Early dust mop cleaning elements were made of
fibers such as cotton which may be treated with an impreg-
nant such as oil to give the fibers a higher capacity for
collecting dust. Woven and nonwoven fabrics have been
employed for this purpose as well as collections of loose
fibers. Nonwoven fabrics are preferred because they are
relatively inexpensive to produce. Dust collecting
elements formed of nonwoven fabric are generally called
` "disposable" because they are discarded instead of being
`~ 15 cleaned and reused.
Not all nonwoven fabrics are suitable candidates
for use as dust collecting elements. Some fabrics will
not attract dust particles because of their physical
nature while others are highly attractive. Some nonwoven
fabrics are too compacted or dense to provide sufficient
openness for dust collection. Some fabrics are too weak
to be employed and disintegrate as they are passed over
the surfa~e~ being cleaned and thus may leaye unsightly
~- residues of the fabric itself.
It is generally recognized that most nonwoven
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fabrics cannot be employed per se as a dust collecting
element without integration by embossing, adhesive bonding
or other means to improve their structural integrity.
Without such integration, most nonwoven fabrics will
disintegrate after only a short period of use as a dust
collecting element.
lntegration by adhesive bonding is not preferred
because it coats the fibers thereby interfering with their
dust collecting ability. Certain embossing techniques are
also undesirable because they either weaken the fabric or
they consolidate it too much thereby reducing its dust
collecting ability.
An improved disposable dust collecting fabric is _-:
provided by the present invention by an embossed nonwoven
fabric comprised of a web of microfibers which may contain
crimped macrofibers. The embossed dust collecting fabric
of the invention has sufficient structural integrity to
provide a commercially acceptable use life, yet it is
sufficiently drapable, lofty and dust-attractive to be
employed to remove dust from hard, smooth surfaces and
other areas where conventional dust collecting fabrics
are employed.
The working face of the nonwoven fabric is
embossed to a limited degree to provide integration of the
normally fragile nonwoven web yet not interfere with its
dust collecting ability. The areas on either side of the
working face adjacent the side edges of the fabric may be
more highly embossed to provide greater structural
. . :
.,
. . ,
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-- 3 --
integrity sufficient to permit handling and installation
of the fabric in certain dust mop frames hav1ng high shear
or other holding means which could damage the fabric.
Specifically the dust collecting fabric of the
invention is characterlzed by being a disposable, drap-
able embossed nonwoven web, at least about l millimeter
thick in the unembossed state, comprising entangled,
discontinuous m~crofibers being capable of self-fusion
under localized pressure and having an average diameter
of about lO microns or less, said fabric belng embossed
to prov1de a uniform pattcrn of embossing llnes compris-
ing about 2g to about 40% of its total surface area and
to bond fibers at points where they touch one another
without loss of individual fiber identity, said nonwoven
web having an elongation value at maximum tensile breaking
in the embossed state of at least about 25%.
The preferred dust collecting fabric of the
invention is characterized by being an elongate dispos-
able, drapable, embossed, binder-free nonwoven web at
least about 2 millimeters thick in the unembossed state
and comprising a homogeneous blend of ta) entangled,
discontinuous microfibers having an average diameter of
about lO microns or less; and (b) crimped macrofibers
about 5 to about lO0 decitex, the weight ratio of said
microfibers to said macrofibers in said web being about
3:7 to about 7:3, at least one of said macrofibers or
said microfibers being capable of self-fusion under
localized pressure, said fabric being embossed to provide
..
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(c) a first uniformly embossed area intermediate the side
edges of said elongate web defining a dust collecting
working face, said first embossed area characterized by
having a uniform pattern of embossing comprising about 10%
to about 40% of the total surface area of said working face;
and (d) second uniformly embossed areas on either side
of said first embossed area, each of said second areas
being more highly embossed than said first area to provide
a uniform pattern of embossing comprising about 25% to
about 65% of the total area of said second areas, said
embossing in said first and second areas-being sufficient
to bond fibers at points where they touch one another
without loss of individual fiber identity.
The invention is further illustrated by reference
to the drawing, wherein;
FIG. 1 is a top plan view of an embossed dust
collecting fabric made in accordance with the present
invention;
FIG. 2 is an enlarged cross sectional view of a
segment of the fabric shown in FIG. 1 taken at line 2-2;
FIG. 3 is a perspective view of a dust mop frame
assembly having the fabric of FIG. 1 mounted for use; and
FIG. 4 is a sectional view of the mop frame
shown in FIG. 3 taken at line 4-4.
FIGS. 5-8 are top plan views o~ other embodiments
of the embossed dust collection fabric made in accordance
with the present invention showing variations in embossing
patterns.
54
FIG, 1 of the drawing shows an embossed nonwoven
fabric 10 made in accordance with the present invention
comprised of a web formed of microfibers which preferably
contains crimped macrofibers. The dust collecting area
or working face 11 of fabric 10 is embossed to a limited
degree to provide integration of the normally fragile
nonwoven web to provide a pattern of continuous cross
embossed lines 12 so that the web can withstand the forces
normally associated with dusting operations. For this
purpose, it has been found that sufficient integration of
the web is obtained when the embossed areas are uniformly
distributed over the working face in the form of lines
which do not exceed about 7 mm in width and which embossed
area comprises at least about 2 percent of the total
surface area of working face 11. Embossing of working
face 11 should not significantly interfere with its dust
collecting ability. Appreciable reduction in dust
collecting properties is noted when embossing exceeds
about 40 percent of the total surface of working face 11.
The preferred degree of embossing comprises about 10%
to about 40% of the total surface of the working face.
The embossed lines of working face 11 may cross
one another to define diamond shaped nonembossed dust
collecting areas 13 which preferably are tapered or
pointed at least in the direction of the main intended
movement of the fabric in use so that the leading portion
of each nonembossed area 13 is smaller than the body of
the nonembossed area 13. Such tapering prolongs the life
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of the non~oven fabric in use.
The embossing lines may be continuous, define
individual, separated geometric shapes such as squares or
circles, or may be a pattern of discontinuous straight or
5 curved lines, such as straight lines (as shown in FIG. 6)
or "J" shapes (as shown in FIGS. 7-8) and the like.
Embossing lines are sufficiently closely spaced to provide
integration of the fibers of the web to prevent substantial
fiber loss during use. For this purpose, the shapes or r
10 lines should preferably not be separated by more than about
2 cm and should not be aligned so as to provide a straight
unembossed zone, which could provide a zone of weakness
where the fabric could fail.
If needed, the fabric 10 may be more highly
15 embossed on either side of working face 11 to provide
highly embossed areas 14. Areas 14 may be more highly
embossed to provide additional structural integrity to the
fabric to make it capable of withstanding the forces
encountered at the more high stress areas in use such as
20 at the point of attachment where the fabric is fastened
into certain types of mop frames. The embossed pattern
in areas 14 may be in a continuous crossed arrangement as
shown in FIG. 1, or a discontinuous arrangement, but are
generally to a greater extent than working face 11,
25 comprising up to about 65 percent of the total area of
each of the more highly embossed areas 14. Mop frames
with fabric attachment means that apply less shearing
action to the edge of the dust cloth may not require more
: .
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-- 7
highly embossed side areas. One example of such an
embossed pattern is shown in FIG. 8.
Any of a wide variety of embossing methods known
in the art may be employed to provide the embossed patterns
described above. For example, conventional heat and
pressure may be used to impart the desired embossed
patterns in the web. Other useful methods include impulse
sealing with pressure which is similar to conventional
heat and pressure but somewhat more refined in that the
web is rapidly heated and cooled under pressure thereby
minimizing any potential undesirable heat transfer,
ultrasonic welding with pressure, rotary pressure emboss-
inq under ambient temoerature~ i.e., without heating, for
example between appropriately shaped hard nip rolls, and
the like. The latter method is the preferred method.
Embossing methods using excessive pressure or excessive
heat and pressure are to be avoided because such methods
produce webs which have very little stretchiness or a low
elongation value. Such webs will readily fail cohesively
in use or as installation on the mop frame is attempted,
with rapid wide-spread splitting of the fabric along the
embossing lines.
Many different embossing patterns are possible
and useful. The embossed lines in the working face of
the fabric of the invention may define shapes which may
include triangles, diamond shapes, squares, rectangles,
polygons, pear-shaped areas, ovals, or may be in the
form of a pattern of discontinuous lines which may be
g65~
straight or curved, and the like.
The nonwoven web employed to produce the embossed
fabric of the present invention is formed of entangled,
discontinuous thermoplastic microfibers having an average ~--
diameter of about 10 microns or less which preferably may
contain up to 70% by weight thermoplastic macrofibers of
about 5 to about 100 decitex to provide additional loft to
enhance entry of dust.
The weight ratio of microfibers to macrofibers in
a preferred web is 3:7 to 7:3 to obtain a preferred balance
of strength and loft in the resultant embossed web for use
as a dust collecting element. The amount of macrofibers,
however, should not be so great as to weaken the web. The
tensile strength and the tear strength of the web decreases
significantly when the macrofiber content exceeds 50 percent
of the total fiber weight.
Wh;le m;crofiber webs containing macrofibers
are preferred for use as dust collecting elements, webs
containing 100% microfibers are also useful, particularly
when embossed with patterns such as are shown in FIGS. 7
and 8, but not when extremely highly embossed. A too
highly embossed 100% microfiber web is characterized by
having a low elongation value (i.e., less than about 25%)
and thus would be subject to rapid cohesive failure as
discussed above.
The microfibers should be capable of self-fusion
under application of localized pressure to permit inte-
gration upon embossing. Preferably, both the macrofibers
- -
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9 ~ 6~
and the microfibers are capable of self-fusing.
The microfibers can be formed of any of a variety
of fiber-forming thermoplastic materials including, for
example, polypropylene, polyethylene terephthalate,
polyethylene, polyamides, and other polymers known in the
art. The preferred thermoplastic material for forming the
microfibers if polypropylene.
The nonwoven webs may be prepared with micro-
fibers which have been melt-blown (prepared by extruding
molten fiber-forming material), solution-blown (prepared
by extruding a solvent solution of fiber-forming material),
or other means.
The macrofibers are crimped to provide loft in
the resultant nonwoven web. Crimped fibers will have a
continuous, wavy, curly or jagged character throughout
their length. Crimping may be in a planar or three
dimensional configuration. The number of crimps, i.e.,
complete waves or cycles, per unit fiber length may vary
rather widely in the macrofibers useful in the invention.
The macrofibers useful in the practice of the invention
typically have more than about one-half crimp per centi-
meter and preferably have at least two crimps per centi-
meter. The amplitude or depth of the crimp fiber may also
vary considerably for the crimped macrofibers useful in
the present invention. Although amplitude and crimp are
difficult to uniformly characterize in numerical values
because of the random nature of many fibers, an indication
of amplitude is given percent crimp. That quantity is
- ~ :, ,. . ~,:
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defined as the difference between the uncrimped length7
measured in the fully extended state, and the crimped
length, measured by saspending the fiber sample with a
weight attached to one end equal to two milligrams per
decitex of fiber, divided by the crimped length and
multiplied by 100. Macrofibers used in the present
invention will generally exhibit an average percent crimp
of at least about 15 percent, preferably at least about
25 percent.
The macrofibers, as a minimum, should have an
average length sufficient to include at least one crimp
and preferably at least three or four crimps. For ease
of handling in preparing the web, when fully extended,
the macrofibers typically average between about 2 and 15
centimeters in length, preferably between 2 and 10
centimeters.
The macrofibers may be formed of any of a wide
variety of synthetic thermoplastic materials. The
preferred macrofibers are crimped staple fibers formed
of polyester, acrylic resin, polyolefin, polyamide, rayon,
polyacetate, and the like. Such staple fibers are readily
commercially available.
The thickness of the web, before embossing,
should be at least 1 millimeter in order to obtain
sufficient strength in the fabric and for the fabric to
be adequately embossed. Preferably, the thickness should
be at least 2 millimeters. The thickness will typically
be less than 30 millimeters because, beyond this, the web
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becomes too bulky and is difficult ~o install in
commercially available mop frames? although such
webs are useful for collecting dusts
The nonwoYen webs useful for preparing
the embossed nonwoven fabric of the present inventiQn
and which contain macrofibers are prepared by introducing
the crimped macrofibers into a stream of microfibers
during the microfiber web formati:on process, A Preferred
method of producing this nonwoven web is disclosed in
United States Patent No. 47118,531, Nonwoven webs which
contain only microfibers are similarly made ~ith the
exception that no macrofibers are used.
One example of prepari-ng a preferred nonwoven
web suited for embossing to produce the embossed
non~oven fabric of the present invention involves
simultaneously preparing melt blown microfi-bers whtle
introducing macrofibers into the stream of freshly
blown microfibers and depositing the collection of
fibers on a suitable carrier. The microfibers may
be produced using conventional equipment. The
macrofibers may first be prepared as a web, for
example, by using a garnet machine or a "~ando-Webberl'
web-forming machine, The macrofiber web is then fed
into the device which separates the macrofibers from
the web and introduces them into the air stream which
is employed to attenuate the microfibers to form the
composite nonwoven web.
. ~ . ~ .
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l~S654
- 12 -
The web may also include other additives to
improve its appearance, strength and/or performance. For
example, impregnants may be added which improVe the dust
collecting ability and/or leave a slight residue to
improve the surface being treatedt Examples of such
impregnants include oils such as hydrocarbon or silicone
oil and paraffin wax.
Webs which are useful in the present invention
may be selected on the basis of certain physical properties.
Useful webs will be sufficiently strong to resist failure
or pulling apart when mounted in a mop frame and used. For
this purpose it is preferred that the web, in the unembossed
state, have an average specific strength of at least about
0.3 (most preferably 0.6) as determined by averaging the
specific strength in the longitudinal direction and in the
transverse direction. Specific strength is the force
required to pull a web apart divided by the weight of the
web. A web which has been embossed should preferablY
have a specific strength of at least about 0.80, most
preferably at least about 1.00.
The specific strength of a nonwoven web may be
determined by weighing a 2.5 cm by 18 cm sample of the
web, placing the narrow ends of the sample between 2.5 cm
wide jaws of an "Instron" tensile testing machine, with
the jaws 10 cm apart, and pulling on the sample at a rate
of 30 cm per minute until the sample breaks. The maximum
- 1 3 'li~!S654
force in grams required to break the sample divided by
the ~eight of the samPle in milligrams is the specific
strength. Samples should be cut in both the transverse
and longitudinal directions and the average determine~,
S The embossed nonwoven webs of the present
invention should also have a moderate degree of
stretchiness which permits at least slight stretching of
the fabric without failure. For this purpose, the
embossed nonwoven webs should have an elongation value
in both the machine di-rection and the transverse direction
at maximum tensile breaking strength of at least 25%?
preferably at least 30%.
Elongation values are determined during the test
for specific strength by measuring the distance the
sample is stretched prior to its breaking at maximum
tensile strength. In evaluating the examples hereinafter
described, it was observed that the elongation value in
the machine direction consistently fell below the
elongation value in the trans~erse direction. Therefore7
the elongatiQn Yalues repQrted herein with respect to the
examples only reflect the lower value of that in the
machine direction.
Webs which are useful in the present invention
should not have appreciable drag ~r resistance when moved
over the surface of the floor. Therefore, the useful
webs of the present inYention in the unembosse~ state
preferably will have a dynamic coefficient of friction
of less than about 1-3, Preferably less than about l,Q~
The dynamic coefficient friction may be
-
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determined by positioning a 15 cm by 15 cm segment of the
web under a 13 cm by 13 cm sled composed of a polyurethane
foam adhered to a wooden block, placing a 454 gram weight
on top of the sled to provide a total weight of 570 grams
and pulling the sled at the rate of 50 cm per minute along
a 60 cm section of vinyl or asbestos tile previously
coated with three applications of commerically available
floor polish (e.g., sold under the trade designation "Step
Ahead"~ by the S.C. Johnson Company), with the web sample
between the tile surface and the polyurethane foam layer,
and measuring the force required to pull. The dynamic
coefficient friction is this force in grams divided by the
total weight of the sled and any additional weight thereon.
Webs which are useful in the present invention
will also be resistant to tearing. For this purpose,
useful webs in the unembossed state preferably will have a
tear strength of at least about 60 grams as determined by
employing a Standard Elmendorf Model No. 60-100 Tearing
Tester, using a 6.5 cm by 28 cm web sample. The tear
strength in both the longitudinal and transverse direction
of the web is measured and averaged.
Nonwoven webs which are useful in the present
invention in the unembossed state preferably will have a
loft or openness of at least about 30 cubic centimeters
per gram. The loft may be determined by weighing a 10
by 20 centimeter section of the web, placing a 10 centi-
meter by 20 centimeter 0.3 millimeter thick aluminum
plate exactly over the sample to avoid discontinuities in
.
. . . - . . . .. ..
- 15 - 11~9i65~
the web sample and measuring the thiçkness in centimeters
at several points on the plate. The loft is a thickness
in centimeters (less the thickness of the plate) times
the area of the web in cm2 divided by the weight of the
5 web in grams.
FI~S. 3 and 4 show an example of a commercially
available dust mop frame 30 sold under the trade desig-
nation "Velmop"~. Such dust mop frames typically include
an elongate flat-faced pad 31 which is preferably
10 compressible (e.g., formed of foam rubber) mounted on a
rigid back-up frame 32 to hold pad 31 in a planar config-
uration and holding means 33 to permit attachment of the
ends 39 of a dust mop cleaning fabric 10, with the working
face 11 of fabric 10 disposed on the flat face of pad 31.
15 The mop frame may also include a universal joint 34 and a
handle holder 35 into which a suitable handle 36 may be
fitted. Holding means 33 in this case is provided by
hinged projecting element 38 which frictionally engages
sidewall 40 to hold fabric ends 39 therebetween. Many
20 other dust mop frames are also known and commercially
available, and that shown in FIGS. 3 and 4 is merely
provided as an illustrative example.
/
EXAMPLES
The invention is further illustrated by the
25 following examples, wherein all parts are by weight,
unless otherwise specified.
EXAMPLE 1
A web, approximately 0.4 to 0.5 cm thick, before
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embossing, having a loft of 80-110 cm3 per gram and a
weight of 50 grams per square meter, was prepared by the
method described in aforementioned
of equal parts of 13 decitex, 3.4 cm polyethylene tere-
phthalate macrofibers having 50% crimp and 0.2 to 4.3
micrometer diameter (average 1.2 micrometer) blown
polypropylene microfibers. This web was embossed at
ambient temperature sequentially between two sets of 25 cm
diameter steel rolls. One set of rolls provided the
embossed pattern on the working face while the other
provided the more highly embossed pattern adjacent the
edges. The working face was embossed with a diamond
pattern, wherein each of the diamond shapes had a minor
axis of 1.5 cm and a major axis of 4 cm to provide a
pattern similar to that shown in FIG. 1.
The more highly embossed side edges of the
web were embossed with a crosshatched pattern as shown
in FIG. 1 of the drawing to provide square shapes 1.3 cm
on edge with 0.24 cm wide embossed lines.
The embossing pressure ranged from about 60 kg
per cm2 to about 260 kg per cm2 for the diamond-shaped
pattern providing the embossed working face and about 270
to 600 kg per cm2 for the more highly reinforced embossed
pattern side edge portions. The web speed through the
embossing rolls was approximately 4.5 meters per minute.
EXAMPLE 2
A 0.4 to 0.5 cm thick web, before embossing,
with a loft of 70 to 80 cm3 per gram and a web weight of
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55 grams per meter was prepared of equal parts of the
blown microfibers described in Example 1 and 53 decitex7
5.5 cm polyethylene terephthalate macrofibers having 51%
crimp. The web was embossed to provide a pattern
substantially as shown in FIG. 1 of the drawing to provide
a nonwoven dust fabric.
EXAMPLE 3
A 0.6 to 0.7 cm web, before embossing, having a
loft of 140-160 cm3 per gram and a web weight of 45 grams
per meter was prepared of equal parts of 17 decitex, 3.8
cm nylon 6:6 having 45% crimp and 0.2 to 7,0 micrometer
diameter (averaging 1.5 micrometers) polypropylene blown
microfibers.
EXAMPLES 4-40
Other embossed nonwoven fabrics were prepared
of the webs described in Table I below.
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Table II reYeals the physical properties of
certain webs in the unembossed state.
Table III compares the physical properties of
certain unembossed webs with those after embossing.
It should be noted that the unembossed areas in
the dust collecting working face of the nonwoven fabric of
the invention will have substantially the same or slightly
less loft and thickness as existed in the unembossed web
before embossing. The unembossed areas in the more highly
embossed side edge portions of the web may be, however,
somewhat more compacted since this part-of the web is not
customarily employed for dust removal. This fact is
reflected in Table III below. In that regard, compare the
loft values for web Example 1, before embossing, with a
diamond pattern and with a crosshatched square pattern.
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- 25 -
Evaluation of Dust Mop Efficiency
The embossed nonwoven fabrics of the present
invention were evaluated as dust collection fabrics against
a competitive nonwoven dust collection fabric sold under
the trade designation "Masslinn"~ which consisted of
hydrocarbon oil impregnated nonwoven rayon fabric. The
evaluation consisted of mounting a 20 by 58 cm segment of
the test dust collection fabric in a dust mop frame having
a flat-faced pad. The dust mop was then employed to clean
a vinyl asbestos test floor polished with four coats of
commercial floor polish (sold under the trade designation
"Step Ahead"~ by the 5. C. Johnson Co.) and covered with
a weighed quantity of a synthetic dirt composition
consisting of the following ingredients:
Percent
Ingredient by Wei~ht
walnut sawdust 25.0
carbon black 1.0
charcoal (6-14 mesh) 15,0
A1203 (60-80 grit) 6.0
A1203 (100-50 grit) 6.0
Flint (180/00) 23.0
pumice 12.0
Fullers earth 12.0
The test floor had a total area of approximately
37 square meters divided into eight approximately equal
rectangular areas of 4.6 square meters each. The test
floor was first precleaned with a conventional cotton
.,
' ~: ' ::
54
- 26 -
string type dust mop until no more than 0.2 grams of dirt
was removed from the 37 square meter area. Then 1 gram of
synthetic soil was uniformly scattered over one 4.6 square
meter rectangular test area. The test mop was weighed
before the cleaning and reweighed after to determine the
amount of synthetic dirt held in the fabric after use. The
amount of synthetic dirt pushed to the end of the 4.6 square
meter test floor was also collected and recorded, after one
pass over the 4.6 square meter area. The sum of the amount
of dirt held and pushed was designated as the total dirt
removed from the floor. The dust mop efficiency was
obtained by multiplying the total removed dirt times 100
and dividing by the total amount of synthetic dirt
initially applied to the test floor.
The mop was used again to clean a larger test
floor area of the same floor type (but with only naturally
occurring dust thereon) and reweighed after each 175 square
meter cleaning pass to determine the use life of the fabric.
The amount of naturally occurring dirt pushed and collected
was also recorded for each 175 square meter area. The
mop was then carefully shaken until successive weight
readings differed by less than 0.02 grams and the steps
described above were repeated, adding a 1 gram sample of
synthetic oil to the next 4.6 square meter test floor
area, using the mop to clean the smaller test floor, as
described above, and then using the mop to clean the
larger test floor, and the cycle repeated until less
than 0.15 grams of synthetic soil was picked up by the
mop, or until the mop was used to clean more than 915
.,
. ~
- 27 - ~1~$~
square meters of test floor. At this point, the mop was
turned over, if it could be used on both sides, reweighed
and the steps repeated until the mop again picked up less
than 0.15 grams of dirt. If the mop was used on 2365
square meters without reaching this minimum usefulness,
the test was also terminated.
The results of this test using the fabric of
Example 1 and a Masslinn "control" fabric are shown in
Table IV below.
.. - ~ ..., . ~ . ,
- . :: ' "' ~ i' .
- 28 ~ 6 ~ 4
TABLE IV
Dirt Dirt
Area Cleaned Held Pushed
(sq. meters) Dust MoP (9 ) (9 ) Efficiençy
55 INITIAL Control 0.49 0.29 0.78
Ex. No. 1 0.28 0.20 0.48
185 Control 0.21 0.23 0.44
Ex. No. 1 0.33 0.25 0.58
365 Control 0.22 0.26 0.48
Ex. No. 1 0.23 0.26 0.49
550 Control 0.20 0.32 0.52
Ex. No. 1 0.31 0.34 0.65
730 Control 0.10* 0.26 0.36
Ex. No. 1 0.45 0.27 0.72
CONTROL) 0.42 0.29 0.71
915 Control 0.19 0.32 0.51
910 Ex. No. 1 0.45 0.30 0.75
Ex 1) 0.42 0.20 0.62
1095 Control 0.08* 0.20 0.28
Ex. No. 1 0.47 0.42 0.89
1275 Control
Ex. No. 1 0.38 0.21 0.59
25 1460 Control
Ex. No. 1 0.37 0.21 0.58
1640 Control
Ex. No. 1 0.32 0.24 0.56
1820 Control
Ex. No. 1 0.33 0.30 0.63
2000 Control
Ex. No. 1 0.27 0.31 1z58
2185 Control
Ex. No. 1 0.37 0.57 0.94
35 2365 Control
Ex. No. 1 0.35 0.23 0.58
* Test terminated
. : ~ ., - ;
- .-: .
6~
- 29 -
As can be seen from the results in Table IV,
embossed nonwoven fabrics in accordance with the present
invention are useful for cleaning more than twice the area
of a commercially available nonwoven fabric dust mop.
Additional cleaning tests as described herein-
above immediately preceding Table IV were performed
employing nonwoven fabrics of Examples 23-28 which were
embossed with a pattern as shown in FIGURE 7. The results
of such tests are set forth in Table V.
TABLE V
Dirt Dirt
Area Cleaned Held Pushed Total
(sq. meters) Ex. (9.) (9.) EfficiencY
Initial 5 23 0.08 0.19 0.27
24 0.02 0.26 0.28
27 0.36 0.16 0.52
28 0.37 0.20 0.57
185 23 0.20 0.26 0.46
24 0.18 0.37 0.55
27 0.19 0.26 0.45
28 0.23 0.28 0.51
365 23 0.18 0.21 0.39
24 0.25 0.16 0.41
27 0.20 0.25 0.45
28 0.22 0.16 0.48
550 23 0.19 0.10 0.29
24 0.13 0.19 0.32
27 0.20 0.28 0.45
28 0.2 0.31 0.57
730 23 0.31 0.15 0.46
24 0.17 0.28 0.45
27 0.20 0.31 0.51
28 0.18 0.24 0.42
910 23 0.16 0.20 0.36
24 0.22 0.18 0.40
27 0.23 0.29 0.62
28 0.22 0.32 0.54
'
,..
- 30 -
TABLE V continued
Dirt Dirt
Area Cleaned Held Pushed Total
(sq. meters) Ex. (9-) (9 ) Efficiency
1090 23 0.17 0.31 0.48
24 0.25 0.15 0.40
27 0.19 0.32 0.51
28 0.19 0.17 0.36
1095 NEW SIDE 23 0.21 0.13 0.34
24 0.17 0.19 0.36
27 0.31 0.30 0.61
28 0.21 0.20 0.41
1275 23 0.31 0.09 0.40
24 0.21 0.25 0.46
27 0.29 0.28 0.57
28 0.18 0.27 - 0.45
1460 23 0.23 0.29 0.52
24 0.20 0.18 0.38
27 0.25 0.28 0.53
28 0.13 0.27 0.40
1640 23 0.29 0.08 0.37
24 ~.19 0.18 0.37
27 0.22 0.32 0.54
1820 23 0.24 0.18 0.42
24 0.20 0.72 0.42
27 0.26 0.22 0.48
2000 23 0.24 0.21 0.45
24 0.25 0.22 0.47
27 0.24 0.32 0.56
2185 23 0.23 0.17 0.40
24 0.19 0.15 0.34
27 0.26 0.40 0.66
-,
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