U.S. patent application number 10/093792 was filed with the patent office on 2003-09-11 for wipe.
This patent application is currently assigned to 3M Innovative Properties Company. Invention is credited to Bergsten, Ronald E., Erickson, John L., Haskett, Thomas E., Pollock, Michele H., Sudo, Yasuo.
Application Number | 20030171051 10/093792 |
Document ID | / |
Family ID | 27804228 |
Filed Date | 2003-09-11 |
United States Patent
Application |
20030171051 |
Kind Code |
A1 |
Bergsten, Ronald E. ; et
al. |
September 11, 2003 |
Wipe
Abstract
A wipe is provided that includes a first wiping member bonded to
a backing member along valleys, whereby the wiping member includes
a plurality of discrete peaks, and an adhesive is provided, in one
embodiment, in the valleys and not on the peaks.
Inventors: |
Bergsten, Ronald E.;
(Minneapolis, MN) ; Erickson, John L.; (White Bear
Lake, MN) ; Haskett, Thomas E.; (Oakdale, MN)
; Pollock, Michele H.; (Inver Grove Heights, MN) ;
Sudo, Yasuo; (Tokyo, JP) |
Correspondence
Address: |
3M INNOVATIVE PROPERTIES COMPANY
PO BOX 33427
ST. PAUL
MN
55133-3427
US
|
Assignee: |
3M Innovative Properties
Company
|
Family ID: |
27804228 |
Appl. No.: |
10/093792 |
Filed: |
March 8, 2002 |
Current U.S.
Class: |
442/327 ;
442/149 |
Current CPC
Class: |
A47L 13/16 20130101;
Y10T 442/60 20150401; B32B 2305/20 20130101; B32B 37/0076 20130101;
Y10T 428/24479 20150115; B32B 27/12 20130101; B32B 3/28 20130101;
Y10T 428/28 20150115; Y10T 428/24802 20150115; Y10T 442/2738
20150401; B32B 37/12 20130101; Y10T 428/24537 20150115; Y10T
442/2754 20150401; A47L 25/005 20130101; Y10T 428/24041
20150115 |
Class at
Publication: |
442/327 ;
442/149 |
International
Class: |
B32B 027/04; B32B
027/12; D04H 003/00; D04H 005/00 |
Claims
We claim:
1. A wipe construction, comprising a substantially continuous
wiping member bonded to a backing member along valleys, whereby the
wiping member includes a plurality of discrete peaks, and an
adhesive is exposed in the valleys.
2. The wipe construction of claim 1, wherein the valleys are
provided in a regular pattern.
3. The wipe construction of claim 1, wherein at least one valley
extends across substantially the entire wiping member.
4. The wipe construction of claim 1, wherein the wiping member is a
unitary nonwoven web.
5. The wipe construction of claim 4, wherein the backing member is
a nonwoven.
6. The wipe construction of claim 4, wherein the backing member is
a continuous film.
7. The wipe construction of claim 1, wherein the adhesive is a
pressure sensitive adhesive.
8. The wipe construction of claim 1, wherein the peaks and valleys
are portions of a corrugated pattern of linear peaks and linear
valleys.
9. The wipe construction of claim 1, wherein the valleys are
provided in a rectilinear grid.
10. The wipe construction of claim 1, wherein the backing member is
also substantially continuous.
11. The wipe construction of claim 1, further comprising chambers
provided between at least some of the peaks and the backing
member.
12. The wipe construction of claim 11, wherein the chambers collect
particles wiped from a surface.
13. The wipe construction of claim 1, wherein substantially all of
the exposed surface of the wiping member is covered with an
adhesive, and a detackifying agent covers the adhesive atop the
peaks.
14. A wipe construction consisting essentially of a substantially
continuous wiping member having peaks and valleys, and an adhesive
exposed in the valleys.
15. The wipe construction of claim 14, wherein the valleys are
provided in a regular pattern.
16. The wipe construction of claim 14, wherein at least one valley
extends across substantially the entire wiping member.
17. The wipe construction of claim 14, wherein the wiping member is
a nonwoven.
18. The wipe construction of claim 14, wherein the adhesive is a
pressure sensitive adhesive.
19. The wipe construction of claim 14, wherein the peaks and
valleys are linear peaks and linear valleys.
20. The wipe construction of claim 14, wherein the valleys are
provided in a rectilinear grid.
21. The wipe construction of claim 14, wherein substantially all of
the exposed surface of the wiping member is covered with an
adhesive, and a detackifying agent covers the adhesive atop the
peaks.
22. A wipe construction comprising a substantially continuous
wiping member bonded to a backing member along valleys, whereby the
wiping member includes a plurality of discrete peaks, and an
adhesive is exposed in the valleys, wherein the wipe construction
demonstrates a Drag Measurement according to the Drag Measurement
Test Method of less than about 1.4 KI.
23. A wipe construction, comprising a substantially continuous
wiping member bonded to a backing member along valleys, whereby the
wiping member includes a plurality of discrete peaks and an
adhesive is exposed in the valleys, the backing member is a
continuous film, and chambers are provided between the peaks and
the film to trap particles.
24. A method of making a wipe construction, comprising the steps
of: (a) providing a substantially continuous wiping member; (b)
providing a backing member; (c) providing an adhesive between the
wiping member and the backing member; and (d) compressing the
wiping member and the backing member together along valleys, so
that at least some adhesive is in at least some of the valleys and
is available to adhere to particles when the wiping member wipes a
surface.
25. The method of claim 24, wherein step (d) comprises the step of
compressing the wiping member and the backing member together using
rollers.
26. The method of claim 24, wherein step (d) is done in the
presence of heat.
27. The method of claim 25, wherein at least one roller has a
substantially smooth surface, and at least one roller has a
patterned surface for forming peaks and valleys in the wipe
construction.
28. A method of making a wipe construction, comprising the steps
of: (a) providing a substantially continuous wiping member and a
backing member that are bonded together along valleys, the wiping
member having discrete peaks; (b) applying adhesive to
substantially the entire exposed surface of the wiping member; and
(c) selectively detackifying the adhesive provided on the peaks, to
leave adhesive exposed in the valleys.
29. The method of claim 28, wherein the adhesive is selectively
detackified using inorganic particulates.
30. The method of claim 28, wherein the adhesive is selectively
detackified using a detackifying agent selected from the group
consisting of titanium dioxide, calcium carbonate, silica, clay and
talc.
31. The method of claim 28, wherein the adhesive is selectively
detackified using a non-tacky organic material.
32. The method of claim 28, wherein the adhesive is selectively
detackified using a detackifying agent selected from the group
consisting of mineral oil, crystalline waxes, low adhesion backsize
coatings, and ethylene copolymers.
33. A method of making a wipe construction, comprising the steps
of: (a) providing a substantially continuous wiping member and a
backing member that are bonded together along valleys, the wiping
member having discrete peaks; (b) applying an activatable adhesive
to substantially the entire exposed surface of the wiping member;
and (c) selectively activating the adhesive that is exposed in the
valleys.
34. The method of claim 33, wherein the adhesive is selected from
the group consisting of thermally-activated adhesives and
plasticizer-activated adhesives.
Description
TECHNICAL FIELD
[0001] The invention relates to a wiping product that is
particularly useful for capturing both ordinary dust or dirt and
heavier particles such as sand.
BACKGROUND OF THE INVENTION
[0002] Cloths and other wiping products have been known for a very
long time, and remarkable improvements in those products have been
infrequent. Most wiping products, or wipes, are made from either a
woven or nonwoven sheet, and are used either by hand or on the end
of a mop handle to move dirt and dust in a desired direction. When
the dirt or dust has been collected, the wipe may be scrunched up
by the user to try to capture the dirt or sand that has been
collected so that it can be shaken out in the trash. This simple
process is repeated thousands or millions of times every day, and
yet it often requires a user who is attempting to pick up larger
particles such as sand to repeat the process several times to pick
up all the sand or heavier particles that have been collected.
[0003] PCT Publication Number WO 01/41622, entitled "Non-apertured
Cleaning Sheets Having Non-Random Macroscopic Three-Dimensional
Character," discloses a cleaning sheet that has recessed and raised
regions. Certain additives can be applied to the sheets to provide
improved performance. Those additives, which may include things
such as waxes, pest control ingredients, antimicrobials, and other
ingredients, are preferably applied in a substantially uniform way
to at least one discrete continuous area of the sheet. However, it
is believed that the cleaning sheets described in this publication
collect dust and particles on the raised portions, which can
subsequently scratch the surface as a user continues to clean that
surface. For example, it is believed that sand particles that are
collected on the raised portions can scratch wood surfaces, which
is obviously undesirable.
[0004] Another publication, Japanese Kokai Patent Application No.
HEI 9-164110, discloses in general terms a cleaning cloth that
includes an adhesive. In at least one embodiment, as shown in FIGS.
3(A) and 3(B), a cleaning cloth includes an adhesive layer
positioned between compressible layers. In FIG. 3(A), the cleaning
cloth is being used with a tool to clean a surface, and the
adhesive layer is not in contact with the surface. In FIG. 3(B),
pressure is applied to the tool so that the adhesive layer comes
into contact with the surface, so as to pick up particles such as
sand and dirt. When the pressure is released, the cleaning cloth
presumably returns to the position shown in FIG. 3(A). Although
cleaning cloths of this type may be useful for some applications,
they appear to require a specific action of the user in order to
make the adhesive effective. The adhesive does not appear to remove
large particles from the floor as part of the normal floor sweeping
process but rather an additional force must be applied for the
adhesive to come into contact with the dust and debris. No details
are provided with respect to the composition or compressive
strength of the cloth, the height difference between the adhesive
and the working surface of the cloth, or the adhesive types.
[0005] PCT Publication Number WO 01/80705 also describes a cleaning
sheet with particle retaining cavities. The cleaning sheet is
prepared by coating a nonwoven backing layer with an adhesive,
followed by lamination of an apertured nonwoven onto the adhesive
layer. The particle retaining cavities have a cross-sectional area
of 1-10 mm and the cleaning sheets often include 0.1-5% adhesive,
as a percentage of the total weight of the cleaning sheet. In
another embodiment, the cleaning sheet may be formed from a single
layer (i.e. no backing layer) of a slightly thicker fabric material
that includes cavities in at least one of its major surfaces. It is
believed that because the amount of adhesive is so small, the
cleaning sheets described in this publication collect dust and
particles on the raised portions, which can subsequently scratch
the surface as a user continues to clean that surface. Furthermore,
since the recessed cavities are discontinuous, there is no path for
the dirt that is missed by the front portion of the cloth to move
back through the cloth and get trapped by the rear portions of the
cloth.
[0006] Another publication, Japanese Kokoku Patent Application No.
3231993, discloses a cleaning sheet that includes a base material
made of a nonwoven fabric, an intermediate sheet having a
pressure-sensitive adhesive coated on both sides, and a surface
sheet that consists of a mesh having many apertures or holes. The
apertured surface sheet is bonded to the base material via the
intermediate double-sided adhesive coated sheet. The cleaning sheet
has first and second areas, in which the second area has an
adhesive surface that traps dirt, and the first area has a surface
that is either nonadhesive or exhibits lower adhesion than the
second area. The elasticity of the first area in the thickness
direction is higher than that of the second area. The cleaning
sheet does not have a continuous path of adhesive with which dirt
particles can come into contact, and thus there is no path for the
dirt that is missed by the front portion of the cleaning sheet to
move back through the cleaning sheet and get trapped by the rear
portions of the cleaning sheet. Another embodiment describes
punching out disks or strips of a nonwoven fabric and bonding these
to the intermediate adhesive sheet at specified intervals instead
of using the surface mesh sheet. Although this embodiment may make
more efficient use of the adhesive areas of the cleaning sheet, it
is believed that this embodiment would be difficult to manufacture
and may not be very durable. No details are provided with respect
to the compositions of various components of the cleaning sheets,
the elasticities of the first and second areas, the height
difference between the adhesive and the working surface of the
cloth, the adhesive types, or the performance characteristics of
the cleaning sheets.
[0007] These and other known wipes seem to suffer from one or more
disadvantages, and accordingly it would be useful to provide a new
wipe that overcomes those disadvantages.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] The present invention will be described with respect to the
appended drawings, in which:
[0009] FIGS. 1 through 6 are elevated, angled side views of wipe
constructions according to the present invention;
[0010] FIG. 7 and FIG. 8 are elevated, angled side views of wipe
constructions according to embodiments of the present invention in
which no backing member is provided;
[0011] FIGS. 9 through 11 are schematic illustrations of processes
for making wipe constructions according to the present
invention;
[0012] FIG. 12 is an enlarged top view photograph (approximately
2.times. magnification) of a wipe construction according to one
embodiment of the present invention; and
[0013] FIG. 13 is an enlarged top view photograph (approximately
2.times. magnification) of a wipe construction according to one
embodiment of the present invention after it had been used to wipe
up particles.
DETAILED DESCRIPTION OF THE INVENTION
[0014] The present invention relates in general terms to a wipe
that can be used to wipe up both small and large particles of dirt,
sand, and other such contaminants. The wipe is three-dimensional,
and thus includes peaks that are separated from each other by
valleys, and in at least one embodiment adhesive is provided in the
valleys. In contrast to known wipes, the adhesive is normally in
contact with the surface to be wiped, and accordingly can collect
both small and large particles of dirt, sand, and the like. In this
way the user does not have to perform an additional step at the end
of the wiping or cleaning process to bring the adhesive into
contact with the dirt and sand. By proper design of the wipe, the
adhesive can contact a surface sufficiently to pick up sand and
other heavy particles, but not to so great a degree that the
coefficient of friction between the wipe and the surface is unduly
high, which can make wiping difficult. These and other beneficial
features of the inventive wipe, as well as method of making and
using such a wipe, will be described in greater detail below.
[0015] A. Physical Characteristics of the Wipe
[0016] One embodiment of a wipe according to the present invention
is shown in FIG. 1. The topography of the wipe is
three-dimensional, and has a wiping surface that includes a number
of peaks or raised regions separated by valleys. An adhesive, or a
substance that has at least some adhesive characteristics such as a
soft wax or a sticky gel, is provided in the valleys but not on the
peaks. Alternatively, if the adhesive is initially provided over
the entire wiping surface, then the adhesive on the peaks should be
de-tackified by, for example, applying a substance such as titanium
dioxide or calcium carbonate on the peaks of the wiping surface and
perhaps a portion of the valleys.
[0017] The peaks and valleys are preferably provided in a regular
pattern or array. For example, the peaks or raised regions can be
provided as generally parallel continuous rows separated by valleys
such as those illustrated in FIGS. 1-8. Alternatively, the peaks or
raised regions can be separated by valleys provided in a
rectilinear grid, so that the raised regions are rectangular or
square, or in other patterns and shapes including but not limited
to diamonds (FIGS. 12 and 13), circles, ovals, triangles, tear
drops, hexagons, and octagons. The peaks and valleys could be
provided in what appears to be a random pattern, but because the
peaks are normally formed by rollers or other devices that would
periodically repeat the random pattern, this arrangement may
actually be a repeating random pattern, or semi-random pattern.
[0018] The height of the peaks is generally uniform and ranges from
about 0.25 millimeters (mm) to about 5 mm, preferably from about
1.5 mm to about 3.9 mm. For samples where the peaks or raised
regions are separated by valleys provided in a rectilinear grid,
such as the embodiments shown in FIGS. 12 and 13, the surface area
of the individual peaks or raised regions ranges from about 9
mm.sup.2 to about 250 mm.sup.2. For corrugated samples where the
peaks or raised regions are provided as generally parallel
continuous rows separated by valleys, such as those illustrated in
FIGS. 1-8, the surface area of the peaks or raised regions ranges
from about 150 mm.sup.2 to about 450 mm.sup.2 (when measured for a
section of a wipe having a surface area of about 645 mm.sup.2).
[0019] The valleys between the peaks range from about 1 mm to about
40 mm wide. For example, distance A illustrated in FIG. 1 and
distance B illustrated in FIG. 12 range from about 1 mm to about 15
mm wide. Distance C in FIG. 12 ranges from about 0.9 mm to about 4
mm wide. Distance D in FIG. 12 ranges from about 4 mm to about 40
mm wide. The dimensions of the samples were measured by optical
microscopy and image analysis of the resulting micrographs.
[0020] A variety of wipe constructions are useful in the context of
the present invention. In a first embodiment, which is illustrated
in FIG. 1, a wipe construction 100 includes a wiping member 200 and
a backing member 300, with a layer of adhesive 250 disposed between
them that bonds the wiping member 200 to the backing member 300 in
the valley regions 110. In areas where compressive force has been
applied to the wipe (with or without heat) to form at least the
valleys 110, and perhaps also the peaks 120 (if a male/female
patterned roller were used, for example), the adhesive in the
adhesive layer 250 permeates the valleys 110 of the first wiping
member 200 and is sufficiently exposed to enable it to retain
particles such as sand and dirt. Thus in those valleys, the wipe
cross-section includes the first wiping member 200, the backing
member 300, and the adhesive layer 250.
[0021] The wiping member 200 can be a knitted, woven, or preferably
a nonwoven fibrous material. The backing member 300 can be a
knitted or woven fabric, a nonwoven web, a thermoplastic film, or
laminates thereof. When the backing member 300 is a nonwoven or a
knitted or woven fabric it may optionally serve as a second wiping
member. The wiping member 200 and the backing member 300 are
preferably continuous, meaning neither the wiping member or the
backing member contain holes, voids, or channels extending
therethrough in the Z direction (i.e. the thickness or height
dimension) that are larger than the randomly formed spaces between
the fibers of the member itself when it is made. In addition, the
wiping member and backing member are each preferably formed as a
single unitary web or film. In the embodiment shown in FIG. 1, when
the backing member 300 is a dense nonwoven or knitted or woven
fabric, or a film, the particles that are wiped up can be caught
and retained within chambers 130 formed between the peaks 120 and
the backing member 300. This may occur because particles that stick
to the adhesive areas are pushed into an adjacent chamber, or
because the particles simply pass through the wiping member as they
are wiped up. This occurs to some extent even when the backing
member is a less dense nonwoven because of the adhesive layer 250.
In any case, the ability of the wipe of this embodiment to collect
particles within the open chambers is believed to be a significant
advantage.
[0022] In a second embodiment, which is illustrated in FIGS. 2 and
3, the wiping member 200 and the backing member 300 and 300a are
bonded together along valleys 110, and adhesive 260 is applied
topically within those valleys. In this embodiment the wiping
member 200 and the backing member 300 may be bonded together by an
adhesive layer as illustrated and described for the embodiment in
FIG. 1. Alternatively, a thermoplastic film or plurality of closely
spaced filaments 300a (shown in FIG. 3) could be extrusion bonded
directly onto the wiping member 200 to form the backing member 300.
Another alternative would be to bond the backing member 300 to the
wiping member 200 by thermal or ultrasonic bonding. Although this
construction may require more expensive tooling (perhaps a
specialized die to apply the adhesive in a specified pattern that
matches the valleys), the resulting construction would have a large
amount of adhesive available to adhere to particles of dust, sand,
crumbs, and the like, and therefore may perform particularly
well.
[0023] In a third embodiment, which is illustrated in FIG. 4, the
wiping member 200 and the backing member 300 are also bonded
together along valleys 110, and adhesive 260 is applied over
substantially all of the exposed surface of the wiping member.
However, a wipe having adhesive over the entire surface would be
difficult to move over a surface because the adhesive would tend to
cause the entire wipe to stick to the surface. Accordingly, the
wipe is preferably modified by detackifying at least a portion of
the wipe, and specifically the peaks 120, so that substantially
only the adhesive in the valleys remains tacky and thus available
to adhere to sand, dirt, and other particles. One potentially
advantageous feature of this embodiment is that the adhesive 260
may remain exposed on the sides 125 of the peaks 120 in addition to
being coated in the bottoms of the valleys, thus providing more
surface area of adhesive available to adhere to particles of dust,
sand, crumbs, and the like. Suitable detackifying agents include
inorganic particulates such as titanium dioxide, calcium carbonate,
silica, clay, and talc. The detackifying agents could be applied by
simply setting the wipe on the detackifying agent with the adhesive
exposed, so that the peaks contact the detackifying agent.
[0024] Alternative agents for selectively detackifying the adhesive
on the peaks include ii non-tacky organic materials like mineral
oil, crystalline waxes, low adhesion backsize coatings, and
polyolefin polymers and copolymers, such as ethylene vinyl acetate.
These materials can be applied by kiss coating using these
materials as fluids, such as solutions, dispersions, emulsions,
radiation curable monomers and oligomers, and hot-melts. Selective
application to the peaks may also be done by spraying at a low
angle, leaving the valleys in the shadow of the peaks. As an
alternative to selectively detackifying the adhesive on the peaks
of a wipe having adhesive coated over the entire surface of the
wiping member, one can also selectively activate the adhesive that
is coated in the valleys. Examples of activatable adhesives include
thermally activated adhesives (see for example PCT Publication
Number WO02/04548) and plasticizer activated adhesive (see for
example PCT Publication Number WO00/56830) non-tacky polymers.
These non-tacky polymers can be coated over the entire surface of
the wipe and selectively rendered tacky in the valleys by
application of heat or plasticizing fluid in these valleys. The
materials may also be dropped as powders in the valleys, and once
positioned, activated by the application of heat or plasticizing
fluids. Alternatively, tacky polymers can be coated over the entire
surface of the wipe and selectively rendered non-tacky on the peaks
by radiation induced cross-linking of the adhesive.
[0025] In a fourth embodiment, which is illustrated in FIG. 5, wipe
construction 100 includes a wiping member 200 and a backing member
300, with a layer of adhesive 250 disposed between them that bonds
the wiping member 200 to the backing member 300 in the valley
regions 110. This embodiment differs from those illustrated in
FIGS. 1-4 in that the chambers 130 beneath the peaks 120 contain
loosely packed fibers, whereas the previous embodiments have
generally open chambers. As described above for the embodiment
illustrated in FIG. 1, in this embodiment adhesive permeates the
first wiping member 200 sufficiently in the valleys 110 to enable
it to retain particles such as sand and dirt. One advantage of this
embodiment is that because the chambers 130 contain fibers, the
peaks 120 are much less likely to collapse under any exerted
pressure. This pressure could be, for example, the pressure exerted
upon the wipe material if wound up in roll form or stacked in a
package, or the pressure exerted simply by a user pushing down
while wiping the surface to be cleaned. If the peaks collapse, the
adhesive may not be sufficiently recessed from the surface of the
wiping member and the cleaning cloth could stick to the surface
being cleaned, resulting in some drag or resistance to wiping,
which is undesirable.
[0026] In a fifth embodiment, illustrated in FIG. 6, the wiping
member 200 and the backing member 300 are bonded together along
valleys 110, and adhesive 260 is applied topically within those
valleys. Similar to the embodiment illustrated and described in
FIG. 5, in this embodiment the chambers 130 beneath the peaks 120
contain loosely packed fibers, and therefore has the same
advantageous properties described above. In this embodiment the
wiping member 200 and the backing member 300 may be bonded together
by an adhesive layer as illustrated and described for the
embodiment in FIG. 5. Alternatively, a thermoplastic film or a
plurality of closely spaced filaments (not shown) could be
extrusion bonded directly onto the wiping member to form the
backing member. Another alternative would be to bond the backing
member to the wiping member by thermal or ultrasonic bonding.
Similar to the embodiments described and illustrated in FIGS. 2 and
3, the wipe construction shown in FIG. 6 would also have a large
amount of adhesive available to adhere to particles of dust, sand,
crumbs, and the like, and therefore may perform particularly
well.
[0027] FIG. 7 illustrates a sixth embodiment of the present
invention, which is similar to the embodiment described and
illustrated in FIG. 4 except that there is no backing member bonded
to the wiping member 200. The formed wiping member has enough
integrity to hold its shape without the need for a separate backing
member. The wiping member could be formed from fibers that
containing a sufficient amount of binder fibers (such as
sheath-core type bicomponent binder fibers) to produce a nonwoven
web with adequate structural rigidity so that a separate backing
member is not required. Alternatively the wipe could be shaped by
bonding a wiping member (for example, a nonwoven web of
polypropylene fibers) to a structured backing member formed from a
material that doesn't adhere well to the wiping member (for
example, a polyester nonwoven web) under adequate heat and pressure
to essentially melt a portion of the fibers in the valley or
recessed regions of the nonwoven wiping member, and subsequently
removing the backing from the wiping member. In this embodiment the
adhesive 260 is applied topically within the valleys 110. In
addition to being potentially lower in cost, another advantage of
this particular wipe embodiment is that it has open chambers 130
which can subsequently be easily filled with additives such as
oils, fragrant powders, soaps, detergents, and the like. A backing
member could then be bonded to the wiping member to retain the
additives within the cavities 130.
[0028] FIG. 8 illustrates a seventh embodiment of the present
invention, which is similar to the embodiment described and
illustrated in FIG. 6 except that there is no backing member bonded
to the wiping member 200. Similar to the wipe embodiment
illustrated in FIG. 7, the formed wiping member of this embodiment
has enough structural rigidity to hold its shape without the need
for a separate backing member.
[0029] The wiping member of the wipe construction of the present
invention can be a knitted or woven fabric, or a nonwoven web.
Preferably the wiping member is a nonwoven web. The nonwoven web
can be prepared by any suitable melt forming or mechanical forming
operation. For example, the nonwoven webs may be carded,
spunbonded, spunlaced, melt blown, air laid, creped, or made by
other processes as are known in the art. Preferred components for
the wiping member of the present invention include nonwoven webs
made from one or more of a variety of thermoplastic polymers that
are known to form fibers. Suitable thermoplastic polymers can be
selected from polyolefins (such as polyethylenes, polypropylenes,
and polybutylenes), polyamides (such as nylon 6, nylon 6/6, and
nylon 10), polyesters (such as polyethylene terephthalate),
copolymers containing acrylic monomers, and blends and copolymers
thereof. Semi-synthetic fibers (such as acetate fibers), natural
fibers (such as cotton), regenerated fibers (such as rayon), and
other non-thermoplastic fibers can also be blended with the
thermoplastic fibers. The fibers typically have a denier of from
about 2 to about 32, more preferably from about 5 to about 15. The
basis weight of the wiping member is preferably from about 10 to
about 90 grams per square meter, and more preferably from about 15
to about 60 grams per square meter.
[0030] The backing member of the wipe construction of the present
invention can be a knitted or woven fabric, a nonwoven web, paper,
a plastic film, or laminates thereof. The backing member may be
permanently or releaseably adhered to the wiping member. When the
backing member is a nonwoven web or a knitted or woven fabric it
may optionally serve as a second wiping member. Preferably the
backing member is a nonwoven web similar to that described above
for the wiping member. The basis weight of the nonwoven backing
member can be within the same ranges described above for the
nonwoven wiping member, but lighter basis-weight nonwovens can
permit more adhesive to penetrate through the backing member to the
side opposite the wiping member, which reduces the amount of
adhesive that is provided in the valleys of the wiping member to
adhere to dirt and sand. Accordingly nonwovens that will be used
for the backing member preferably have a basis weight of more than
15 to 20 grams per square meter.
[0031] If a plastic film is used as the backing member, a
polyolefin (such as polypropylene or polyethylene), a polyamide, a
polyester, or other film may be used. The thickness of the film may
be from about 0.012 mm (0.5 mils) to about 0.075 mm (3 mils). If
the film is extrusion bonded to a nonwoven wiping member, then it
is important that the nonwoven wiping member and the film backing
member be of compatible materials so that adequate bonding between
the two members is obtained.
[0032] Suitable adhesives for use with the present invention
include any that are capable of being tacky at room temperature,
including both adhesives that are initially tacky and those that
are initially non-tacky but which can be activated to become tacky.
Suitable adhesives include any pressure-sensitive adhesives,
including materials based on acrylates, silicones,
poly-alpha-olefins, polyisobutylenes, rubber block copolymers (such
as styrene/isoprene/styrene and styrene/butadiene/styrene block
copolymers), styrene butadiene rubbers, synthetic isoprenes,
natural rubber, and blends thereof. The pressure-sensitive
adhesives may be coated from solvent, from water, radiation
polymerized, or hot melt processed. These pressure-sensitive
adhesives may or may not be crosslinked. Crosslinking can be done
by well-known methods, including chemical, ionic, physical, or
radiation-induced processes. If the adhesive is to be pushed
through the wiping member, materials with low viscosity are
preferred. To improve the cohesive strength of the adhesive once
deposited into the valleys of the wiping member, some crosslinking
may be used. To allow for low viscosity for easy processing while
providing for good cohesive strength, adhesives with physical
crosslinking, ionic crosslinking, or some form of post-crosslinking
are preferred. Post-crosslinking can be carried out by exposing the
adhesive to radiation, such as electron-beam or high intensity
ultraviolet (UV) radiation. For UV crosslinking, it may be
desirable to incorporate a photo-receptive group in the polymer
backbone to facilitate the crosslinking reaction. U.S. Pat. No.
4,737,559 (Kellen et al.) discloses examples of such UV-crosslinked
adhesives. Physical or ionic crosslinking provide the advantage
that the process is thermally reversible, making it particularly
preferred for hot-melt processing. Physically-crosslinked adhesives
include those based on rubber block copolymers. Examples of
synthetic rubber block copolymers include Kraton.TM. commercially
available from Kraton Polymers of Houston, Tex., and Vector.TM.
commercially available from Exxon-Mobil of Houston, Tex. These
block copolymers are typically formulated into pressure sensitive
adhesives by compounding them with tackifiers and/or oils. Details
about the formulation of these types of adhesives can be found in
the Handbook of Pressure Sensitive Adhesive Technology, Second
Edition, chapter 13 (D. Satas editor, Van Nostrand Reinhold
publisher, N.Y.) Other physically crosslinked adhesives include
macromer grafted polymers as disclosed in U.S. Pat. No. 5,057,366
(Husman et al.).
[0033] The adhesives useful in this invention may be tacky under
both dry and wet conditions. Adhesives with high tack under wet
conditions are disclosed in a PCT Publication Number WO 00/56828.
The pressure-sensitive adhesives may also be coated from water in
the form of a latex or dispersion. As discussed in the Handbook of
Pressure-Sensitive Adhesive Technology 2.sup.nd edition (D. Satas
editor, Van Nostrand Reinhold, N.Y., 1989), these adhesives may be
based on polymers like natural rubber, acrylates,
styrene-butadienes, and vinyl ethers. Especially when coated
directly on a porous, woven, or nonwoven substrate, the neat latex
adhesives may not be viscous enough to prevent excessive
penetration into the substrate. Whereas the viscosity and flow of
the latex adhesive may be controlled by the solids content of the
material, it may be more beneficial to formulate the latex with
thickening agents. Thickening agents are typically categorized as
water-soluble polymers or associative thickeners. I Their nature
and mechanism of operation are described in Emulsion Polymerization
and Emulsion Polymers, chapter 13, page 455 (P. Lovell and M.
El-Aasser editors, John Wiley and Sons, NY, 1997). As discussed in
the Handbook of Pressure-Sensitive Adhesive Technology 2.sup.nd
edition, chapter 16, page 473 (D. Satas editor, Van Nostrand
Reinhold, N.Y., 1989), in the case of pressure-sensitive adhesives,
particular care has to be taken in the selection of the thickening
agent so it does not interfere with the adhesive properties.
[0034] The amount of adhesive that should be applied depends on a
number of factors, including the tackiness of the adhesive, the
degree to which the adhesive must be squeezed through the wiping
member, the characteristics of the wiping member and the backing
member (particularly in regard to the amount of adhesive that can
be pushed through each member), the degree to which the adhesive
adheres to surfaces (and thus makes wiping difficult), and other
such factors. The amount of adhesive should be sufficient enough
for the wipe to capture both small and large particles of various
shapes and consistencies, such as lint, dust, hair, sand, food
particles, gravel, twigs, leaves, and the like, without having
excess adhesive that could create drag and make wiping difficult or
that could transfer to the surface being cleaned. The adhesive may
be applied as a continuous layer or as a discontinuous layer and
may be applied by a variety of methods such as stripe coating,
pattern coating, spray coating, screen printing, etc., as is known
in the art. The wipe constructions will typically include from
about 10 weight % to about 200 weight % of adhesive, more typically
from about 30 weight % to about 130 weight % of adhesive, based on
the weight of the input nonwoven wiping member (or the combined
weight of the input nonwoven wiping member and the backing member,
if a backing member is present). Also, the ratio between areas that
have adhesive and those that either have no adhesive or a
de-tacktified adhesive can range from about 75:25 to about
20:80.
[0035] It may be useful to provide valleys (and adhesive) that
extend across an entire dimension of the wiping member. For
example, if a linear groove pattern is used, the grooves can extend
all the way across the wiping member. The same may be true of a
pattern of raised diamonds or other shapes, in which the valleys
extend (though not necessarily in a straight line) across the
wiping member. This provides a continuous path of adhesive with
which dirt particles can come into contact, and thus the surface to
be cleaned is exposed to adhesive across the entire surface of the
wipe, which ensures more uniform wiping performance.
[0036] B. Methods of Making a Wipe
[0037] There are a number of suitable ways of making a wipe in
accordance with the present invention. For example, a system of the
general type disclosed in U.S. Pat. Nos. 5,256,231, 5,616,394,
5,643,397, and European Patent No. EP 341993B1 (all Gorman et al.),
the contents of which are each incorporated by reference herein,
can be used to feed together the wiping member and the backing
member, apply a layer of adhesive between them, and then form them
into a three-dimensional wipe of the type described. FIG. 9
schematically illustrates a method and equipment for forming a wipe
of the type illustrated in FIG. 1. The method illustrated in FIG. 9
generally comprises forming a nonwoven wiping member 200 so that it
has raised regions or peaks 120 and valley portions 110, extruding
an adhesive layer 250 between the wiping member and a backing
member 300, which bonds the valley portions 110 of the wiping
member 200 to the backing member 300 to form a three-dimensional
wipe 100. This method is performed by providing first and second
corrugating members or rollers 26 and 27 each having an axis and
including a plurality of circumferentially spaced generally axially
extending ridges 28 around and defining its periphery, with spaces
between the ridges 28 adapted to receive portions of the ridges 28
of the other corrugating member, 26 or 27, in meshing relationship
with the nonwoven 200 between the meshed ridges 28. The corrugating
members 26 and 27 are mounted in axially parallel relationship with
portions of the ridges 28 meshing generally in the manner of gear
teeth; at least one of the corrugating members 26 or 27 is rotated;
and the nonwoven 200 is fed between the meshed portions of the
ridges 28 of the corrugating members 26 and 27 to generally
corrugate the nonwoven 200. The corrugated nonwoven 200 is retained
along the periphery of the second corrugating member 27 after it
has moved past the meshed portions of the ridges 28. An adhesive
layer 250 is extruded from a die 24 into a nip formed between the
second corrugating member 27 and a cooling roller 25 while
simultaneously supplying a backing member 300 into the nip formed
between the second corrugating member 27 and the cooling roller 25
along the surface of roller 25. This results in the extruded
adhesive layer 250 being deposited between the backing member 300
and the nonwoven 200 and bonding the backing member 300 and the
nonwoven 200 along the valley portions 110. Some adhesive from the
surface of the backing layer is forced by nip pressure at the nip
points between and through the fibers of the nonwoven web 200 due
to the heat and pressure present. The nonwoven wipe laminate 100 is
then carried partially around the cooling roller 25 to complete
cooling.
[0038] The method used for forming a wipe of the types illustrated
in FIGS. 2 and 3 is similar to and uses the same equipment
illustrated in FIG. 9, except that instead of extruding an adhesive
layer to bond the backing member 300 onto the nonwoven web 200, the
backing member 300 or a plurality of spaced filaments 300a is
formed and bonded to the nonwoven web 200 by extruding or
coextruding the thermoplastic backing member 300 or 300a in a
molten state from the die 24 into the nip formed between the second
corrugating member 27 and the cooling roller 25. This embeds the
fibers of the nonwoven web into the film or filament backing
member. Adhesive 260 is then applied topically within the valleys
110 to form the wipe 100.
[0039] Alternatively, a wipe of the type illustrated in FIG. 2
could be formed by thermally or ultrasonically bonding the backing
member 300 to the wiping member 200 and then topically applying
adhesive 260 within the valleys 110 of the wipe 100.
[0040] FIG. 10 schematically illustrates a method and equipment for
forming a wipe of the type illustrated in FIG. 5. This method is
similar to and uses the same equipment illustrated in FIG. 9,
except that the first corrugating member 26a has a generally flat
surface. In this wipe embodiment loosely packed fibers remain in
the chambers 130 beneath the peaks 120.
[0041] The method used for forming a wipe of the type illustrated
in FIG. 6 is similar to and uses the same equipment illustrated in
FIG. 10, except that instead of extruding an adhesive layer to bond
the backing member 300 onto the nonwoven web 200, the backing
member 300 or a plurality of spaced filaments 300a is formed and
bonded to the nonwoven web 200 by extruding or coextruding the
thermoplastic backing member 300 or 300a in a molten state from the
die 24 into the nip formed between the second corrugating member 27
and the cooling roller 25. This embeds the fibers of the nonwoven
web into the film or filament backing member. Adhesive 260 is then
applied topically within the valleys 110 to form the wipe 100.
[0042] A wipe of the type illustrated in FIG. 5 can also be
prepared by the method and equipment schematically illustrated in
FIG. 11, which illustrates a two-roll process rather than the
three-roll process as described above. This method is performed in
FIG. 11 by providing first and second corrugating members or
rollers, 26 and 27a having axes generally in the same plane and of
about the same diameter. Corrugating member 27a has a generally
flat surface. Corrugating member 26 is the recessed patterned
member or roll and is generally geared to or driven by corrugating
member 27a so that they move in opposite rotational directions at
the same circumferential speed. The temperature of the first
corrugating member 26 is generally the same as the temperature of
the second corrugating member 27a, and both members are generally
heated to assist in the corrugation and also the flow of the
adhesive. The nonwoven wiping member 200 is carried over the
surface of the corrugating roller 26 and into the nip formed
between the first and second corrugating rollers. Adhesive 250 is
extruded from a die 24 into the nip while simultaneously supplying
a backing member 300 along the surface of the second corrugating
roller 27a and into the nip. This results in an extruded adhesive
layer 250 being deposited between the backing member 300 and the
nonwoven wiping member 200 that bonds the backing member 300 and
the nonwoven 200 along the valley portions 110. Some adhesive from
the surface of the backing layer is forced by nip pressure at the
nip points between and through the fibers of the nonwoven web 200
due to the heat and pressure present. The nonwoven wipe laminate
100 is then carried partially around the corrugating roller 27a to
complete cooling.
[0043] A wipe of the type illustrated in FIG. 6 can also be
prepared by the method and equipment similar to that schematically
illustrated in FIG. 11, except that the wipe could be formed by
thermally or ultrasonically bonding the backing member 300 to the
wiping member 200 and then topically applying adhesive 260 within
the valleys 110 of the wipe 100.
[0044] It should also be noted that the types of wipes illustrated
in FIGS. 1 and 5 can alternatively be prepared by using a
pre-formed adhesive coated backing member instead of extruding a
hot melt adhesive layer in-line. This adhesive coated nonwoven
backing member is then fed between the second patterned roller and
the cooling roller under pressure (with or without heat) to
facilitate the adhesive flow through the nonwoven wiping member
into the valleys. If the backing member is releasably adhered to
the wiping member, the end user could remove the backing member and
attach the wipe to a cleaning implement such as to the bottom of a
mop head.
[0045] The methods for forming the wipe constructions illustrated
in FIGS. 7 and 8 are similar to and can use some of the same
equipment as shown in FIGS. 9-11. If the nonwoven wiping member is
formed from fibers that contain a sufficient amount of binder
fibers (such as sheath-core type bicomponent binder fibers) to
produce a nonwoven web with adequate structural rigidity, there may
be no need to supply a separate backing member. Alternatively, the
wipe may be shaped by bonding a nonwoven wiping member (for
example, a nonwoven web of polypropylene fibers) to a structured
backing member formed from a material that doesn't adhere well to
the wiping member (for example, a polyester nonwoven web), under
adequate heat and pressure to essentially melt a portion of the
fibers in the valley or recessed regions of the nonwoven wiping
member. If the backing member is then subsequently removed from the
wiping member, a nonwoven web with adequate structural rigidity may
be obtained. For these wipe embodiments the adhesive 260 is applied
topically within the valleys 110 after the wiping member is
formed.
[0046] It should be noted that two-sided wipe constructions
(i.e.--wipe constructions having top and bottom wiping surfaces
that include peaks or raised regions separated by valleys) could
also be prepared from any of the embodiments illustrated in FIGS.
1-7. Laminating two of the wipe constructions together using
various laminating means as are known in the art. Alternatively,
this could be accomplished by adding additional corrugating members
to the equipment illustrated in FIGS. 9-11 (See for example, U.S.
Pat. No. 5,681,302, FIGS. 4 and 5 and the associated
description).
[0047] C. Methods of Using the Wipe
[0048] Another way to characterize the wipe of the present
invention is by the way it performs. Before turning to Examples
that measure that performance, some important performance
characteristics should be noted. First, the wipe should pick up
sand, dirt, and other relatively large particles that are not
normally picked up by a simple cloth wipe. Second, the wipe should
have the proper drag when wiped across a surface. The drag
associated with the wipe of the present invention is a combination
of the frictional forces between the non-adhesive portions of the
wipe and the surface, and the adhesive forces between the adhesive
portions of the wipe and the surface. If too much adhesive is
exposed, or the adhesive that is exposed is too tacky, then the
wipe will catch and drag on the surface, and users will quickly
become dissatisfied. If too little adhesive is exposed, or if the
adhesive that is exposed is not sufficiently tacky, then the wipe
probably will not retain as much dirt, sand, and the like as it
should. If the height of the peaks is too high or the resistance to
compression is too high then less of the adhesive will be exposed
to the dirt and the wipe will not be as effective.
[0049] D. Other Features of the Invention
[0050] Additives may be added to the wipes of the present invention
to provide other desirable properties. For example, detergents,
abrasives, disinfectants, cleaning chemicals, polishes, oils, or
waxes may be provided on or beneath the wiping member, so that
those additives can act on a surface over which the wipe is moved.
The fibers of the wiping member may be hydrophilic or may be
hydrophilically modified (for example with a surfactant) so that
both dry and damp wiping applications are possible.
[0051] It may also be desirable to color the wipe, perhaps even in
a fluorescent color, and this can be done by adding a colorant to
the materials used to make the wiping member, backing member, or
both. It can also be done after manufacturing, perhaps by using a
dye to color the wipe, although care should be exercised to insure
that the dye has no harmful effect on the performance or appearance
of the adhesive, and does not transfer to any surface being
wiped.
[0052] The wipes of the present invention may be used alone as a
dusting cloth or in combination with a cleaning implement or tool
such as a mop, a glove or mitt, a duster, or a roller and the like.
The wipes can also be packaged in roll form or as a stack of sheets
for easy dispensing.
[0053] Test Methods
[0054] Sand Removal Test A
[0055] Sand removal was measured by distributing 2 grams
(designated as W.sub.1) of sand (90-175 .mu.m mean diameter) on the
surface of a 60 cm.times.243 cm vinyl floor. A sample of the wipe
was attached to the head (wiping member facing away from the head)
of a ScotchBrite.TM. High Performance Sweeper mop available from
the Minnesota Mining and Manufacturing Company (3M Company) of St.
Paul, Minn. Samples made with a liner were tested by removal of the
liner and adherence of the sample to a piece of spunbond
polypropylene (20 g/m.sup.2, available from Avgol Ltd., Holon,
Israel). The sweeper head with the wipe attached was weighed and
recorded as W.sub.2. The sweeper head was attached to the sweeper
stick and the test sample was pushed once over the entire flooring
area (i.e. one pass over every area of the flooring that sand on
it) with minimal pressure applied to the handle of the sweeper mop.
The head was again removed from the stick and its weight was
measured (W.sub.3). The weight percent of the sand removed by the
wipe from the surface was calculated as follows:
% Sand Removed=[(W.sub.3-W.sub.2)/W.sub.1].times.100
[0056] Sand Removal Test B
[0057] Sand removal was measured according to the Sand Removal Test
A except that the wipe samples were attached to the head of a 10
cm.times.25 cm Pledge Grab-It.TM. Sweeper mop available from S. C.
Johnson Inc. of Racine, Wis.
[0058] Sand Removal Test C
[0059] Sand removal was measured according to Sand Removal Test A
except that sand having a larger mean diameter of 175-250 .mu.m was
used for testing.
[0060] Sand Removal Test D
[0061] Sand removal was measured according to test Sand Removal
Test B except 1.54 grams of sand (W.sub.1) rather than 2 grams of
sand were applied on the surface of a 46 cm.times.243 cm vinyl
floor and sand having a larger mean diameter of 175-250 .mu.m was
used for testing.
[0062] For all the sand removal tests, the data reported in the
Tables are an average of at least two tests.
[0063] Drag Measurement
[0064] A Model 225-1 Friction/Peel Tester available from
Thwing-Albert Instrument Company (Philadelphia, Pa.) was equipped
with a force transducer (model number MB-2KG-171, also available
from Thwing-Albert). The friction tester was set to a speed of 110
inch (279.4 cm) per minute and a time of 5 seconds. A piece of
black glass was cut to 66.5 cm.times.21.5 cm and mounted on the
friction tester. The glass was cleaned using Windex.TM. and a
ScotchBrite.TM. Microfiber Cleaning Cloth available from 3M
Company. A sample of wiping cloth was cut to 4 inch.times.6 inch
(10.2 cm.times.15.2 cm) and was attached to the test fixture along
the 6 inch side. Samples made with a liner were tested by removal
of the liner and adherence of the sample to a piece of thermally
bonded carded polypropylene web having a basis weight of 31 grams
per square meter (FPN336D, available from BBA Nonwovens of
Simpsonville, S.C. A 500 gram weight (7.6 cm.times.12.7 cm in size)
was placed on the wiping cloth and the friction tester was run. The
kinetic coefficient of friction (KI) was recorded. The data
reported in the Tables are an average of at least two tests.
[0065] Nonwoven Materials
[0066] Nonwoven N.sub.1 was a flat spunbond polypropylene nonwoven
web having a basis weight of 20 grams per square meter, available
from Avgol Corporation of Holon, Israel.
[0067] Nonwoven N.sub.2 was a flat carded thermally bonded
polypropylene nonwoven web having a basis weight of 31 grams per
square meter, available as FPN 336D from BBA Nonwovens of
Simpsonville, S.C.
[0068] Nonwoven N.sub.3 was a flat unbonded carded nonwoven web
having a basis weight of 56 grams per square meter and prepared
from 9 denier polypropylene fibers, available from FiberVisions of
Covington, Ga.
[0069] Nonwoven N.sub.4 was a flat unbonded carded nonwoven web
having a basis weight of 90 grams per square meter and prepared
from 32 denier polyester fibers, available from Kosa of Charlotte,
N.C.
[0070] Nonwoven N.sub.5 was a spunlace polyester nonwoven web
having a basis weight of 31 grams per square meter, available from
Veratec Corp. of Walpole, Me.
[0071] Nonwoven N.sub.6 was a flat unbonded carded nonwoven web
having a basis weight of 30 grams per square meter and prepared
from 9 denier polypropylene fibers, available from FiberVisions of
Covington, Ga.
[0072] Nonwoven N.sub.7 was a flat unbonded carded nonwoven web
having a basis weight of 30 grams per square meter and prepared
from an 80/20 mixture of 9 denier polypropylene fibers (available
from FiberVisions of Covington, Ga.) and 1.5 denier rayon fibers
available from Lenzing Fibers, Lowland Tenn.
[0073] Nonwoven N.sub.8 was spunlace rayon nonwoven web having a
basis weight of a 25 grams per square meter, available as S7125
from Shinwa Co, Japan.
[0074] Nonwoven N.sub.9 was a flat unbonded carded web having a
basis weight of 50 grams per square meter prepared from 9 denier
polypropylene fibers, available from FiberVisions of Covington,
Ga.
[0075] Nonwoven N.sub.10 was a spunlace polyester nonwoven web
having a basis weight of 45 grams per square meter, available from
DuPont, Wilmington, Del.
EXAMPLES
Example 1
[0076] A wipe of material was prepared using the method and
equipment illustrated in FIG. 9 except that the first and second
intermeshing patterned rollers (corrugating members 26 and 27,
respectively) that were used were machined with a diamond pattern.
A wiping member (nonwoven N.sub.1) was fed into the nip between
first and second intermeshing patterned rollers that were machined
with a diamond pattern such that there were approximately 9
diamonds per square inch (6.45 cm.sup.2) with a space between each
diamond. Each diamond was machined to have a flat top-surface
having a width of about 8 mm. The patterned sheet of nonwoven was
shaped such that there were raised regions or peaks and anchor
portions that formed valleys along the nonwoven web, each raised
region or peak being about 3 mm high and each anchor portion being
about 4 mm wide. The first patterned roller was heated to
93.degree. C., whereas the second patterned roller was heated to
149.degree. C. A hot melt adhesive commercially designated HM-19902
(available from H. B. Fuller Company of St. Paul, Minn.) was
extruded through a 2 inch (5.1 cm) Davis single screw extruder onto
a backing member (nonwoven N.sub.2). The adhesive was extruded
along the periphery of the cooling roller just prior to the nip at
a die temperature of 135.degree. C. at a basis weight of 60 grams
per square meter. The formed wiping member and the adhesive coated
backing member moved through the nip between the second patterned
roller 27 and the cooling roller 25 (38.degree. C.) at a pressure
of about 300 pounds per linear inch. The ratio of adhesive to
non-adhesive areas on the resultant wipe material was 52:48.
Example 2
[0077] Example 2 was prepared according to the procedure described
for Example 1 above with the following changes. Nonwoven N.sub.3
was used as the wiping member that was fed into the nip between the
first and second intermeshing patterned rollers, and a smooth steel
roll was used as the first roller instead of a patterned roll.
Instead of extruding a hot melt adhesive layer, a pre-formed
adhesive coated backing member was used and was prepared in the
following manner. A hand-spread adhesive was prepared by dissolving
a 60 grams sample of dry Kraton.TM. polymer HM-1902 (available from
HB Fuller, St. Paul, Minn.) in 40 grams of toluene. The solution
was agitated overnight to get a good uniform mixture. The solution
was then coated onto a silicone release liner using a knife coater
and was oven dried at 70.degree. C. for 10 minutes, yielding a 3
mil (0.076 mm) thick dry adhesive coating. The sample was left
overnight and was then laminated at room temperature onto a
polypropylene backing member (nonwoven N.sub.2) using a 4.5 pound
rubber roller. The release liner was then removed. This adhesive
coated nonwoven backing member was then fed between the second
patterned roller and the cooling roller at a pressure of 300 pounds
per linear inch.
Example 3
[0078] Example 3 was prepared using the method and equipment
illustrated in FIG. 10. The procedure was similar to the procedure
described in Example 1 above except that nonwoven N.sub.3 was used
as the wiping member, a smooth steel roll was used as the first
roll instead of a patterned roll, and the HM-1902 adhesive was
extruded at 113.degree. C. at a basis weight of 29 grams per square
meter.
Example 4
[0079] Example 4 was prepared according to the procedure described
in Example 3 except that nonwoven N.sub.4 was fed into the process,
a smooth steel roll was used as the first roller, and the HM-1902
adhesive was extruded at 113.degree. C. at a basis weight of 40
grams per square meter.
Example 5
[0080] Example 5 was prepared according to the procedure described
in Example 1 except nonwoven N5 was used as the wiping member, the
second patterned roller was heated to 190.degree. C. and the
cooling roll was operated at 10.degree. C. A preformed adhesive
coated backing member was used and was prepared in the following
manner. A hand spread adhesive was prepared by dissolving a 60 gram
sample of polymer in 40 grams of toluene. The polymer was comprised
of 100 parts of Zeon Rubber 3620 (a styrene-isoprene-styrene block
copolymer available from Nippon Zeon, Japan), 85 parts
Wingtack.RTM. (tackifier available from Goodyear Corporation of
Akron, Ohio), 1.5 parts Irganox.RTM. 1076 (antioxidant available
from Ciba Specialty Chemicals of Tarrytown, N.Y.) and 1.5 parts
Cyanox.RTM. LTDP (available from Cytec Industries of West Paterson,
N.J.). The solution was agitated overnight to get a good uniform
mixture. The solution was then coated onto a silicone release liner
using a knife coater and was oven dried at 70.degree. C. for 10
minutes, yielding a 3 mil (0.076 mm) thick dry adhesive coating.
The sample was left overnight and was then laminated at room
temperature onto N5 using a 4.5 pound (2.0 kilogram) rubber roller.
The release liner was then removed. This adhesive coated nonwoven
backing member was then fed between the second patterned roller and
the cooling roller at a pressure of 250 pounds per linear inch.
Example 6
[0081] Example 6 was prepared according to the procedure described
in Example 2 except that 100 parts of a hot melt acrylate copolymer
having a composition of 55% 2-ethylhexyl acrylate and 45% acrylic
acid were blended with 70 parts of the plasticizer UCON 50HB400
(available from Dow Chemical Company of Midland, Mich.) and this
was used as the adhesive on the pre-formed adhesive coated backing
member.
Example 7
[0082] Example 7 was prepared using the method and equipment
illustrated in FIG. 11. A wiping member (nonwoven N6) was fed into
the nip between first corrugating roller 26 (149.degree. C.) and
second corrugating roller 27a (21.degree. C). Adhesive HM-1902 was
extruded at 190.degree. C. at a basis weight of 60 grams per square
meter onto a 1 mil (0.025 mm) polyester film backing member
(available from 3M Company, St. Paul, Minn.). The wiping member and
the adhesive coated backing member moved through the nip between
the first corrugating roller and second corrugating roller at a
pressure of 370 pounds per linear inch.
Example 8
[0083] Example 8 was prepared according to the procedure described
in Example 3 above except that nonwoven N.sub.7 was used, the
adhesive was extruded at 190.degree. C. at a basis weight of 60
grams per square meter, and the second patterned roller and the
cooling roller (21.degree. C.) were operated at 370 pounds per
linear inch.
Comparative Example C.sub.1
[0084] Comparative Example C.sub.1 was a ScotchBrite.TM. High
Performance Sweeper Disposable Cloth available from 3M Company.
Comparative Example C.sub.2
[0085] Comparative Example C.sub.2 was a Pledge Grab-It.TM.
Electrostatic Cloth available from S. C. Johnson, Racine, Wis.
Comparative Example C.sub.3
[0086] Comparative Example C3 was made according to PCT Publication
Number WO 01/80705. Nonwoven N.sub.2 was sprayed with Super 77
spray adhesive (available from 3M Company of St. Paul, Minn.) and
was laminated to a sample of Comparative Example C.sub.2 that had
apertures cut into the cloth. The adhesive was sprayed so that the
amount of dried adhesive was approximately 1.8% of the total
nonwoven weight. The adhesive was allowed to dry overnight. Circles
7.5 mm in diameter were cut out of the cloth used as Comparative
Example C.sub.2, with 4 circles removed from each square inch of
cloth. The ratio of adhesive to non-adhesive areas was 27:73.
Comparative Example C.sub.4
[0087] Comparative Example C.sub.4 was prepared according to
Example 1 except that no adhesive was applied.
[0088] Examples 1-8 and Comparative Examples C.sub.1-C.sub.4 were
evaluated using the Sand Removal Test Methods A, B, C, and D, and
the Drag Measurement Test Method described above. The results are
presented in Table I.
1TABLE I % Sand % Sand % Sand Drag Removal Removal Removal
Measurement Example (Test A) (Test B) (Test C) (KI) Example 1 70 --
88 0.41 Example 2 57 -- -- 0.49 Example 3 53 -- 68 -- Example 4 65
-- -- 0.27 Example 5 71 -- -- -- Example 6 -- -- 72 -- Example 7 --
-- 87 -- Example 8 -- -- 73 -- C1 50 -- 62 0.05 C2 -- 30 -- 0.18 C3
-- 38 -- -- C4 13 -- -- --
[0089] The performance values for Example 5 versus Comparative
Example C.sub.4 show that the presence of the adhesive has a
significant effect. Also note that the presence of the adhesive in
Comparative Example C.sub.3 does not vary the performance
significantly from the non-adhesive Comparative Example
C.sub.2.
Example 9
[0090] Example 9 was prepared in a manner similar to that described
for Example 1 above. Nonwoven web N.sub.10 was fed into the nip
between first and second intermeshing patterned rollers that were
machined with a diamond pattern such that there were approximately
38 diamonds per square inch with a space between each diamond. Each
diamond was machined to have a flat top-surface having a width of
about 4.5 mm. The patterned sheet of nonwoven was shaped such that
there were raised regions or peaks and anchor portions that formed
valleys along the nonwoven web, each raised region being about 1.8
mm high and each anchor portion being about 1.2 mm wide. The first
patterned roller was heated to 66.degree. C., whereas the second
patterned roller was heated to 149.degree. C. A 5 mil (0.13 mm)
film of polyoctene (available from 3M Company) on a release liner
was fed into the nip between the second patterned roller and the
cooling roller at a pressure of 450 pounds per linear inch. The
ratio of adhesive to non-adhesive areas was 43:57.
Example 10
[0091] Example 10 was prepared according to Example 9 except that
the first and second intermeshing patterned rollers were run open
(not touching each other). Each raised region or peak was
approximately 0.25 mm high.
Example 11
[0092] Example 11 was prepared by heating flat patterned plates to
149.degree. C. using a platen press. Nonwoven N.sub.9 was placed on
top of the heated patterned plate, covered with a layer of release
liner and the platen press was closed for 15 seconds at 15 pounds
per square inch. The textured side of the sample was then sprayed
with Super 77 spray adhesive at a dry weight of 60% of the weight
of the nonwoven and was placed in a 66.degree. C. oven for 15
minutes. The peaks of the sample were de-tackified by masking the
sample with the patterned plate and sprinkling talc onto the peaks.
The excess talc was removed using a vacuum. The samples formed in
this manner had raised circles with approximately 1.8 raised
portions per square inch, a peak width of 15 mm, a peak height of
3.9 mm, and a distance between adjacent peaks of 9 mm. The ratio of
adhesive to non-adhesive areas was 50:50.
Example 12
[0093] Example 12 was made using flat patterned plates and an iron
at approximately 150.degree. C. Nonwoven N.sub.8 was used and was
laminated to a 2.5 mil (0.064 mm) polypropylene film (available
from the 3M Company of St. Paul, Minn.). The corrugated pattern was
such that there were 16 stripes in a 100 mm.times.100 mm area. A
solvent based pressure sensitive adhesive
(iso-octylacrylate/acrylamide 96/4) was applied onto the recessed
section of the corrugation pattern by transfer coating using a
silicone rubber stamp. The coating weight of the adhesive was 0.6
grams per 100 mm.times.300 mm area. The height of the peaks was 2.1
mm, the width of the valleys was 1.0 mm, and the ratio of adhesive
to non-adhesive areas was 20:80.
Comparative Example C.sub.6
[0094] Comparative Example C.sub.6 was formed according to Example
11 except that no adhesive was applied to the nonwoven.
[0095] Examples 9-12 and Comparative Example C.sub.6 were evaluated
using the Sand Removal Test Methods B and D and the Drag
Measurement Test Method described above. The results are presented
in Table II.
2 TABLE II % Sand % Sand Drag Removal Removal Measurement Example
(Test B) (Test D) (KI) Example 9 -- -- 0.13 Example 10 -- -- 0.71
Example 11 -- 65 0.84 Example 12 69 -- -- Comparative -- 20 0.37
Example C.sub.6
[0096] Comparison of performance between Example 11 and Comparative
Example C.sub.6 showed that the presence of the adhesive has a
large effect.
[0097] Various modifications and alterations of this invention will
become apparent to those skilled in the art without departing from
the scope and principles of this invention, and it should be
understood that this invention is not to be unduly limited to the
illustrative embodiments set forth hereinabove.
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