U.S. patent application number 11/574762 was filed with the patent office on 2007-12-27 for floor cleaning pads and preparation thereof.
Invention is credited to Louis Charmoille, Delphine Coppens, Edouard Koroloff, Didier Legros, Sylvain Speeg.
Application Number | 20070298697 11/574762 |
Document ID | / |
Family ID | 33186752 |
Filed Date | 2007-12-27 |
United States Patent
Application |
20070298697 |
Kind Code |
A1 |
Charmoille; Louis ; et
al. |
December 27, 2007 |
Floor Cleaning Pads and Preparation Thereof
Abstract
An abrasive article (1) for use on a rotary cleaning machine
having, on one side, a first abrasive face (2) having a first
abrasive nature and, on the other side, a second abrasive face
having a second abrasive nature abrasive face comprising a lofty,
three-dimensional, non-woven web of fibres bound together, at the
places where they contact, by a binder material; wherein each
abrasive face is provided with a visual indicator to inform the
user of its abrasive nature.
Inventors: |
Charmoille; Louis; (Jouy Le
Moutier, MN) ; Legros; Didier; (Beauchamp, FR)
; Koroloff; Edouard; (Taverny, FR) ; Speeg;
Sylvain; (Vallangoujard, FR) ; Coppens; Delphine;
(Herouville, FR) |
Correspondence
Address: |
3M INNOVATIVE PROPERTIES COMPANY
PO BOX 33427
ST. PAUL
MN
55133-3427
US
|
Family ID: |
33186752 |
Appl. No.: |
11/574762 |
Filed: |
September 1, 2005 |
PCT Filed: |
September 1, 2005 |
PCT NO: |
PCT/US05/31475 |
371 Date: |
March 6, 2007 |
Current U.S.
Class: |
451/425 ;
51/293 |
Current CPC
Class: |
B24D 13/147 20130101;
B24B 7/186 20130101; B24D 11/005 20130101 |
Class at
Publication: |
451/425 ;
051/293 |
International
Class: |
B24B 7/18 20060101
B24B007/18; B24D 11/00 20060101 B24D011/00 |
Foreign Application Data
Date |
Code |
Application Number |
Sep 9, 2004 |
GB |
0420054.9 |
Claims
1-22. (canceled)
23. An abrasive article for use on a rotary cleaning machine
having, on one side, a first abrasive face having a first abrasive
nature and on the other side, a second abrasive face having a
second abrasive nature different from the first: each abrasive face
comprising a lofty, three-dimensional, non-woven web of fibres
bound together, at the places where they contact, by a binder
material; wherein each abrasive face is provided with a visual
indicator to inform the user of its abrasive nature.
24. An abrasive article as claimed in claim 23 in which the visual
indicators are the colour of the abrasive faces.
25. An abrasive article as claimed in claim 23 comprising a
circular pad having a diameter of at least 200 mm and a thickness
of at least 10 mm having an upper abrasive face and a lower
abrasive face, the pad comprising a lofty, three-dimensional
non-woven web of fibres bound together at places where they contact
by a first binder containing a colouring material of a first colour
and, coated over one of said upper and lower abrasive faces and
penetrating to a depth of from 1 to 7 mm, a second binder
containing a colouring material of a second colour which contrasts
with said first colour, the pad being free of a middle flexible,
wet-laid non-woven strata layer having uniform directional strength
in all longitudinal directions.
26. An abrasive article as claimed in claim 25, in which the second
binder imparts, to the face of the pad over which it is coated, a
different abrasive nature from that of the other face of the
pad.
27. An abrasive article as claimed in claim 25, in which at least
one of the first and second binders contains a material that causes
the abrasive faces of the pad to have different abrasive
natures.
28. An abrasive article as claimed in claim 25, in which said first
binder optionally contains finely divided abrasive material, and
the second binder contains finely divided abrasive material that is
more aggressive than any abrasive material present in the first
binder.
29. An abrasive article as claimed in Claim 28, in which the other
of said upper and lower abrasive cleaning faces is impregnated with
a binder containing a colouring material of said first colour and
finely divided abrasive material which is less aggressive than the
abrasive in the second binder.
30. An abrasive article as claimed in claim 23, in which the web
comprises polyester and/or nylon fibres.
31. An abrasive article as claimed in claim 23, in which the web
comprises fibres having a denier of from 15 to 200 and a length of
from 20 to 70 mm.
32. An abrasive article as claimed in claim 25, which has a
thickness of from 10 to 25 mm and a diameter of from 200 to 785
mm.
33. A floor cleaning pad as claimed in claim 23, in which the
visual indicators comprise combinations of first and second colours
selected from White/Red, White/Blue, Red/Blue, Blue/Brown and
Green/Black.
34. A method of making a floor cleaning pad for use on a rotary
floor cleaning machine comprising: providing a lofty,
three-dimensional, non-woven web of fibres having a thickness of at
least 10 mm and comprising upper and lower major faces,
impregnating said web with a first thermosetting binder containing
a colouring material of a first colour, to bond the fibres together
at places where they contact, coating one of said upper and lower
major faces with a second thermosetting binder containing a
colouring material of a second colour which contrasts with said
first, such that said second binder penetrates to a depth of from 1
to 7 mm and imparts to that one face an abrasive nature that is
different from the abrasive nature of the other face, heating said
binder resins at a temperature and for a sufficient time to form
infusible insoluble cured products thereof, and cutting the
resulting web into circular pads having a diameter of at least 200
mm.
35. A method as claimed in claim 34 in which the first
thermosetting binder optionally contains finely divided abrasive
material, and the second binder contains finely divided abrasive
material that is more aggressive than any abrasive material present
in the first binder.
36. A method as claimed in claim 34 in which the first
thermosetting binder is applied by roll coating.
37. A method as claimed in claim 34 in which the second
thermosetting binder is applied by spray coating.
38. A method as claimed in claim 34 comprising the additional step
of coating the other of said upper and lower cleaning surfaces with
a thermosetting binder containing a colouring material of said
first colour and finely divided abrasive material which is less
aggressive than the abrasive in the second thermosetting
binder.
39. A method as claimed in claim 38 in which said additional step
comprises spray coating the thermosetting binder.
40. A method as claimed in claim 34, in which the second binder
penetrates the web to a depth of from 2 to 4 mm
41. A method as claimed in claim 34, in which the web comprises
polyester and/or nylon fibres.
42. A method as claimed in claim 34, in which the web comprises
fibres having a denier of from 15 to 200 and a length of from 20 to
70 mm.
43. A method as claimed in claim 34, in which the floor cleaning
pad has a thickness of from 10 to 25 mm and a diameter of from 200
to 785 mm.
44. A method as claimed in claim 34, in which the combinations of
first and second colours are selected from White/Red, Red/Blue,
Blue/Brown and Green/Black.
Description
FIELD OF THE INVENTION
[0001] This invention relates to floor cleaning pads used to clean
hard surface floors, such as, wood, vinyl, stone etc. and to their
preparation. In particular the invention relates to reversible
floor cleaning pads for use on floor cleaning machines designed to
rotate at speeds less than 1200 revolutions per minute.
BACKGROUND TO THE INVENTION
[0002] Lofty, open, non-woven three-dimensional abrasive articles
are known for use in cleaning and polishing floors and other
surfaces. Examples of such non-woven surface treating articles are
non-woven pads made according to the teaching of U.S. Pat. Nos.
2,958,593, 3,537,121, 4,437,271, 4,893,439, 5,030,496, 5,282,900,
5,458,962 and 6,261,164. Examples of such abrasive products are
commercially available under the registered trade mark
"Scotch-Brite" from 3M United Kingdom plc.
[0003] The pads of this type are typically cut in a circular shape
to be used in conjunction with a floor polishing machine. Typical
sizes range from 8'' (203 mm) to 28'' (711 mm) in diameter. The
pads may also be rectangular or of other shapes depending upon the
equipment with which they are to be used. Such machines have a
means for engaging or holding a pad thereon while rotating the pad
against the surface being treated.
[0004] The pads are available in any of a wide variety of types to
provide many functions. Some pads are extremely abrasive and are
desirably used for wax stripping and cleaning floor surfaces which
are heavily encrusted with soil. Other are mildly abrasive and are
typically used for floor polishing, with or without the prior
application of wax. The different abrasive properties of the pads
are achieved by appropriate selection of the fibres, resin binders
and abrasive materials used in their construction.
[0005] In order to assist the operators in the correct selection
and identification of a floor pad to perform a particular task, the
floor pads are made in distinctive colours, each colour being
associated with a particular product specification. For example,
Scotch-Brite.RTM. floor pads that are currently commercially
available in the United Kingdom include the following:
Scotch-Brite.RTM. Black Floor Pad--for wet stripping
Scotch-Brite.RTM. Brown Floor Pad--for wet or dry stripping
Scotch-Brite.RTM. Green Floor Pad--for wet scrubbing
Scotch-Brite.RTM. Blue Floor Pad--for general cleaning
Scotch-Brite.RTM. Red Floor Pad--for spray cleaning
Scotch-Brite.RTM. White Floor Pad--for dry polishing
[0006] There are occasions when an operator of a floor cleaning
machine may need to use two different pads. For example, the
operator may be dry polishing a floor e.g. in a supermarket, office
etc., when he finds an area of the floor which has been soiled and
requires cleaning prior to polishing. He must either clean the area
manually or change the pad on the machine to a pad suitable for
cleaning. Since the pads are large, spare pads are not carried on
the floor cleaning machine and it is necessary for the operator to
acquire an appropriate pad from a store or the like which may be
some distance from the working area.
[0007] U.S. Pat. No. 4,536,911 and Re 32978 disclose a reversible
hard floor cleaning pad for use with super high speed and ultra
high speed machines. The pad includes a first porous non-woven
air-layered web having an upper, floor cleaning surface and an
opposite lower surface. The upper cleaning surface is adapted to
clean hard surface floors, such as wood or vinyl, when placed on
the floor and rotated by a flooring machine about a vertical axis
passing through the centre of the first web at super high speeds of
at least 1000 revolutions per minute. A second porous non-woven
air-layered web having a lower, floor cleaning surface and an
opposite upper surface is disposed parallel to and spaced from the
first web with the first web lower surface facing the second web
upper surface. The second web lower cleaning surface is also
adapted to clean hard surface floors when placed on the floor and
rotated at super high speeds. A flexible wet-laid non-woven strata
layer having uniform directional strength and an upper layer
surface and an opposite lower layer surface is positioned between
the first and second webs. The first web lower surface is glued
directly to the upper layer surface and the second web upper
surface directly to the lower layer surface with an elastomer,
resin-reinforced non-flammable adhesive. A multi-layer reversible
pad is thereby formed having generally uniform strength in all
horizontal directions thereby eliminating any tearing and shredding
problem.
[0008] The upper and lower layers may be formed differently. For
example one may be formed of natural fibres and the other of
synthetic fibres. Also the resins used to impregnate one layer can
include abrasive so that layers can be used for cleaning and the
other for high speed buffing.
[0009] The manufacturing process for the reversible cleaning pads
is complex, involving the preparation of two separate webs and
equipment to laminate the two webs together sandwiching separate
strata layers therebetween.
[0010] U.S. Pat. No. 4,078,340 discloses a low density abrasive pad
having a mildly abrasive surface and a more aggressively abrasive
surface, thus being especially suited for cleaning and scouring
kitchen utensils, said mildly abrasive surface being capable of
cleaning but not harmfully scratching non-stick plastic pan
coatings and other plastic surfaces, said more aggressively
abrasive surface being capable of scouring soiled pots and pans,
said pad having a void volume of about 85% to 97% and consisting
essentially of in combination: [0011] a lofty, non-woven mat,
having a thickness of at least about 1.3 cm when incorporated in
said pad and extremely high void volume, consisting essentially of
crimped mixed denier nylon, polyester, or mixtures of both nylon
and polyester filaments at least 2.5 cm in length when fully
extended, said mixed denier filaments consisting essentially of
small diameter filaments on the order of 10 to 20 denier and larger
diameter filaments on the order of 40 to 70 denier wherein the
weight ratio of large diameter filaments to small diameter
filaments is in the range of 1:3 to about 3:1, [0012] said fibres
being bonded together at points where they cross and contact each
other with a soapy water-resistant tough thermoset first resin
binder which contains a finely divided soft abrasive material
having a Mohs hardness on the order of 3 to 7 and a particle size
on the order of 180 grade or finer, and [0013] coated over one
entire major surface of said pad and penetrating into said pad to a
depth on the order of 1 to 7 mm, a soapy water-resistant tough
second resin binder which contains finely divided hard abrasive
material having a Mohs hardness in excess of 8 and a particle size
on the order of 280 grade or finer.
[0014] The size of the pad is convenient to fit the user's hand.
For example, circular discs should not be larger than 15 cm in
diameter nor should rectangular shapes be larger than 15 cm in
length or width.
SUMMARY OF THE INVENTION
[0015] The present invention provides a simple, effective
construction of reversible abrasive pads for use on a rotary
cleaning machine, such as a floor cleaning machine, and a process
for their production. The invention is also concerned with the
provision of reversible abrasive pads that enable the efficiency of
a surface-cleaning operation, particularly a floor cleaning
operation, to be increased.
[0016] According to the present invention there is provided an
abrasive article for use on a rotary cleaning machine having, on
one side, a first abrasive face having a first abrasive nature and,
on the other side, a second abrasive face having a second abrasive
nature different from the first; each abrasive face comprising a
lofty, three-dimensional, non-woven web of fibres bound together,
at the places where they contact, by a binder material; wherein
each abrasive face is provided with a visual indicator to inform
the user of its abrasive nature.
[0017] In an abrasive article in accordance with the invention, the
abrasive nature of an abrasive face may be determined by one or
more of several factors, for example the fibres used in the
non-woven web; the presence of abrasive particles, and the nature
(including the size) of those abrasive particles when present; the
nature of the binder material; and the presence of additives (for
example materials such as short fibres, or friction modifiers) in
the binder material. Accordingly, the abrasive nature of one
abrasive face of the abrasive article can be made to differ from
the abrasive nature of the other face by adjusting one or more of
those factors.
[0018] According to one embodiment of the present invention there
is provided a floor cleaning pad for use on a rotary floor cleaning
machine comprising a circular pad having a diameter of at least 200
mm and a thickness of at least 10 mm having an upper cleaning face
and a lower cleaning face, the pad comprising a lofty,
three-dimensional non-woven web of fibres bound together at places
where they contact by a first binder containing a colouring
material of a first colour and, coated over one of said upper and
lower cleaning faces and penetrating to a depth of from 1 to 7 mm,
a second binder containing a colouring material of a second colour
which contrasts with said first colour, the pad being free of a
middle flexible, wet-laid non-woven strata layer having uniform
directional strength in all longitudinal directions.
[0019] According to a further aspect of the present invention there
is provided a method of making a floor cleaning pad for use on a
rotary floor cleaning machine comprising: [0020] providing a lofty,
three-dimensional, non-woven web of fibres having a thickness of at
least 10 min and comprising upper and lower major faces, [0021]
impregnating said web with a first thermosetting binder containing
a colouring material of a first colour to bond the fibres together
at places where they contact, [0022] coating one of said upper and
lower major faces with a second thermosetting binder containing a
colouring material of a second colour which contrasts with said
first colour, such that said second binder penetrates to a depth of
from 1 to 7 mm and imparts to that one face an abrasive nature that
is different from the abrasive nature of the other face, [0023]
heating said binder resins at a temperature and for a sufficient
time to form infusible insoluble cured products thereof, and [0024]
cutting the resulting web into circular pads having a diameter of
at least 200 mm.
BRIEF DESCRIPTION OF THE DRAWINGS
[0025] FIG. 1 shows one embodiment of a floor cleaning pad in
accordance with the invention.
DESCRIPTION OF PREFERRED EMBODIMENTS
[0026] By way of example only, abrasive articles in accordance with
the invention will be described with reference to the accompanying
drawing which is a perspective view of a floor cleaning pad.
[0027] The invention provides abrasive articles, such as the
reversible floor cleaning pad 1 shown in the drawing, having two
cleaning faces with different abrasive natures, typically different
aggressiveness. In the drawing, only the upper cleaning face 2 of
the pad is visible. Thus, the cleaning pad 1 is capable of
conducting two different operations depending on the side in use.
One cleaning face has a visual indicator, e.g. indicia or a colour
which contrasts with a visual indicator on the other cleaning face
thereby allowing the operators to clearly identify the correct
cleaning surface to be used. The visual indicators may conveniently
be the colour of the abrasive faces. The cleaning pads may
conveniently have cleaning faces having the same colour and same
aggressiveness as the currently commercially available products
with identical aggressiveness and same colour on each side.
[0028] The floor cleaning pads 1 may be made by slight modification
to the existing processes for preparing floor cleaning pads and do
not require the lamination of two separate webs to middle strata
layer having uniform directional strength in all longitudinal
directions.
[0029] Currently floor pads are made by forming a web of fibres and
roll coating the web by passing it through a pair of rollers wetted
by a slurry of finely divided abrasive particles in a coloured
binder formulation. The selection of binder, abrasive and colour
depend upon the intended aggressiveness of the product and, in some
cases, the abrasive particles may not be required. After roll
coating the web is cured in an oven. The fibres of the web are
bonded to each other at the contact points.
[0030] In some cases, particularly pads used for buffing, the
resulting web is simply cut to form the pads. In other cases the
web is subject to additional treatment by impregnating each surface
with a slurry of finely divided abrasive in a coloured binder
formulation.
[0031] The binder and abrasive used for this treatment may be
different from that used in the roll coating. Generally the
additional treatment is applied by spray coating one surface with
the slurry to not only cover the surface but allow penetration of
the slurry to impregnate several millimetres of the web. The
treated web is then cured in an oven and the treatment repeated on
the second surface. Thereafter the cured web is cut into circular
pads.
[0032] In accordance with the invention pads which would not have
been subject to the second treatment stage are treated by applying
to one surface a slurry of finely-divided abrasive in a binder
formulation having a colour contrasting with that of the binder
present in the web in a manner which allow penetration of the
slurry to a depth of 1 to 7 mm. The abrasive used is more
aggressive than any already present in the web. The impregnated web
is cured and cut into circular pads. The resulting pad 1 has a less
aggressive cleaning face of one colour and a more aggressive
cleaning face (for example, the face 1) in a contrasting colour
(not indicated in the drawing).
[0033] In the case of pads which are currently made by a process
having the two stage treatment, one surface is treated with a
slurry of abrasive in a binder formulation that will typically have
the same colour as the binder present in the web. However, the
second surface is treated with a different slurry of abrasive in a
binder formulation having a contrasting colour in a manner allowing
penetration of the slurry in the web to a depth of 1 to 7 mm. The
abrasive is more aggressive than that present in the web and other
cleaning surface. The web is cured and cut into circular pads. The
resulting pad has a less aggressive cleaning face of one colour and
a more aggressive cleaning face (for example, the face 1) in a
contrasting colour (not indicated in the drawing).
[0034] An alternative process for making floor pads 1, or other
abrasive articles in accordance with the invention, comprises
forming two lofty three-dimensional, non-woven webs of fibres bound
together at places where they contact by a binder material. Each
web has an abrasive face on at least one side, the said abrasive
face of one web having a first abrasive nature, the said abrasive
face of the other web having a second abrasive nature different
from the first, and each of the said abrasive faces being provided
with a visual indicator of its abrasive nature. The webs are
laminated together on their other sides, for example by a hot-melt
adhesive, to form a composite web having the said abrasive faces as
its outer faces, from which abrasive articles are cut. In that
case, the junction between the two webs may be visible on the edge
of the abrasive article, as indicated by the broken line 3 on the
floor pad shown in the drawing.
[0035] In that alternative process, each of the original webs from
which the composite web is formed may be made by forming a web of
fibres and roll coating the web by passing it through a pair of
rollers wetted by a slurry of finely divided abrasive particles in
a coloured binder formulation. The selection of binder, abrasive
and colour depend upon the intended aggressiveness of the product
and, in some cases, the abrasive particles may not be required.
After roll coating the web is cured in an oven. In some cases, at
least one of the webs is subject to additional treatment by
impregnating at least one face with a slurry of finely divided
abrasive in a coloured binder formulation.
[0036] The floor pad 1 may optionally be provided with a pre-cut
central portion 4, indicated in broken lines in the drawing. This
central portion can be removed by the user to provide a central
aperture in the pad, if required, depending on the type of floor
cleaning machine on which the pad is to be used.
[0037] The open, lofty, non-woven webs used in the present
invention are preferably made from crimped, staple, thermoplastic
organic fibres such as polyamide and polyester fibres.
[0038] Although crimping is not necessary to the invention,
crimped, staple fibres can be processed and entangled into
non-woven webs by conventional web forming machines such as that
sold under the trade name RANDO WEBBER which is commercially
available from the Curlator Corporation. Methods useful for making
non-woven webs suitable for use in the invention from crimped,
staple synthetic fibres are disclosed in U.S. Pat. Nos. 2,958,593
and 3,537,121 which are incorporated herein by reference.
Continuous crimped or uncrimped fibres may also be used, but these
tend to increase frictional drag or the article.
[0039] The staple fibres may be stuffer-box crimped, helically
crimped as described, for example, in U.S. Pat. No. 4,893,439, or a
combination of both, and the non-woven webs useful in making
non-woven surface treating articles of the invention may optionally
contain up to about 50 weight percent melt-bondable fibres, more
preferably from about 20 to about 30 weight percent, to help
stabilise the non-woven web and facilitate the application of the
coating resin.
[0040] Suitable staple fibres known in the art are typically made
of polyester or polyamide, although it is also known to use other
fibres such as rayon.
[0041] Melt bondable fibres useful in the present invention can be
made of polypropylene or other low-melting polymers such as
polyesters as long as the temperature at which the melt bondable
fibres melt and thus adhere to the other fibres in the non-woven
web construction is lower than the temperature at which the staple
fibres or melt bondable fibres degrade in physical properties.
Suitable and preferable melt bondable fibres include those
described in U.S. Pat. No. 5,082,720, mentioned above. Melt
bondable fibres suitable for use in this invention must be
activatable at elevated temperatures below temperatures which would
adversely affect the helically crimped fibres. Additionally, these
fibres are preferably co-processable with the helically crimped
fibres to form a lofty, open unbonded non-woven web using
conventional web forming equipment. Typically, melt bondable fibres
have a concentric core and a sheath, have been stuffer box crimped
with about 6 to about 12 crimps per 25 mm, and have a cut staple
length of about 25 to about 100 mm. Composite fibres have a
tenacity of about 2 to 3 g/denier. Alternatively, melt bondable
fibres may be of a side by side construction or of eccentric core
and sheath construction.
[0042] Preferred fibres for use in this invention are helically
crimped polyester staple fibres and stuffer box crimped polyester
staple fibres, particularly helically crimped polyethylene
terephthalate (ET) staple fibres and stuffer box crimped PET staple
fibres.
[0043] U.S. Pat. No. 3,595,738 incorporated herein by reference,
discloses methods for the manufacture of helically crimped
bicomponent polyester fibres suitable for use in this invention.
The fibres produced by the method of that patent have a reversing
helical crimp. Fibres having a reversing helical crimp are
preferred over fibres that are crimped in a coiled configuration
like a coiled spring. However, both types of helically crimped
fibres are suitable for this invention. U.S. Pat. Nos. 3,868,749,
3,619,874 and 2,931,089 all of which are incorporated herein by
reference, disclose various methods of edge crimping synthetic
organic fibres to produce helically crimped fibres.
[0044] Helically crimped fibres typically and preferably have from
about 1 to about 15 full cycle crimps per 25 mm fibre length, while
stuffer box crimped fibres have about 3 to about 15 full cycle
crimps per 25 mm fibre length. As taught in the '439 patent, when
helically crimped fibres are used in conjunction with stuffer box
crimped fibres, preferably the helically crimped fibres have fewer
crimps per specified length than the stuffer box fibres.
[0045] Crimp index, a measure of fibre elasticity, preferably
ranges from about 35 to about 70 percent for helically crimped
fibres, which is about the same as stuffer box crimped fibres.
Crimp index can be determined by measuring fibre length with
appropriate "high load" attached, then subtracting fibre length
with appropriate "low load" attached, and then dividing the result
value by the high load fibre length and multiplying that value by
100. (The values of the appropriate "high load" and "low load"
depend on the fibre denier. For fibres of the invention having 50
100 denier, low load is about 0.1 to 0.2 grams, high load is about
5 to 10 grams.) The crimp index can also be determined after
exposing the test fibres to an elevated temperature, e.g.
135.degree. C. to 175.degree. C. for 5 to 15 minutes, and this
value compared with the index before heat exposure. Crimp index
measured after the fibre is exposed for 5 to 15 minutes to an
elevated temperature, e.g. 135.degree. C. to 175.degree. C., should
not significantly change from that measured before the heat
exposure. The load can be applied either horizontally or
vertically.
[0046] The length of the fibres employed is dependent upon the
limitation of the processing equipment upon which the non-woven
open web is formed. However, depending on types of equipment,
fibres of different lengths, or combinations thereof, very likely
can be utilised in forming the lofty open webs of the desired
ultimate characteristics specified herein. Fibre lengths suitable
for helically crimped fibres preferably range from about 60 mm to
about 150 mm whereas suitable fibre lengths for stuffer box fibres
range from about 20 to about 70 mm, generally 20 to 40 mm.
[0047] The thickness (denier) of the fibres used in the non-woven
surface treating articles of the present invention is not critical.
As is generally known in the non-woven field, larger denier fibres
are preferred for more abrasive articles, smaller denier fibres are
preferred for less abrasive articles, and fibre size must be
suitable for lofty, open, low density abrasive products. The denier
of fibres typically used for non-woven abrasive articles of the
invention may range broadly from about 6 to about 800, preferably
from 15 to about 200 denier, more preferably from abut 50 to about
100 denier. Finer deniers than about 15 may result undesirable
frictional drag when the non-woven surface treating articles of the
invention are attached to conventional floor machines (i.e. one
designed to rotate and force the abrasive article against the
surface and thus finish the surface). Fibre deniers larger than
about 200 may reduce drag, but torque from the floor machine may
twist the web rather than rotate the web as is desired.
[0048] Natural fibres may also be employed, preferably in
combination with synthetic fibres. Vegetable fibres such as hemp,
jute and the like may be used and animal hair fibres may be
employed. One preferred animal hair fibre is hog's hair fibre. If
natural fibres are employed, they preferably and typically range
from about 0 to about 30 weight percent of the total weight of
fibres.
[0049] Uncoated fibrous webs useful in the invention typically and
preferably have a weight ranging from about 300 to about 1000
grams/meter.sup.2 ("gsm"), more preferably ranging from about 300
to about 600 gsm. The binder coating weight on the fibrous web is
generally about 1.0 to about 4.0 times the weight of the uncoated
web, more preferably from about 1.0 to about 3.0 times the weight
of the uncoated web.
[0050] The non-woven surface floor cleaning pads 1 in accordance
with the invention may be attached to and used with conventional
floor cleaning and buffing machines, such as those known under the
trade designations. Nilfisk Advance 421 A or Nilfisk Advance UB
624, commercially available from Nilfisk-Advance A/S, Sognevej 25,
Brondby, Denmark; or TASKI ergodisc onmi or TASKI ergodisc 400,
commercially available from JohnsonDiversey France, 94133
Fontenay-sous-Bois Cedex, France. For efficient operation using
these types of machines, the non-woven cleaning pads 1 in
accordance with the invention preferably have a non-compressed
thickness of at least 1.0 cm, more preferably ranging from about 2
cm to about 4 cm. As mentioned above, the thickness is dependent
upon the fibre denier chosen for the particular application. If the
fibre denier is too fine, the non-woven surface treating articles
of the invention will be less lofty and open, and thus thinner,
resulting in the article tending to be more easily loaded with
floor finish and/or detritus from the floor or surface being
treated.
[0051] Binders suitable for use in the non-woven floor cleaning
pads 1 in accordance with the invention may comprise any
thermoplastic or thermoset resin suitable for manufacture of
non-woven articles, but it will be clear to those skilled in the
art of such manufacture that the resin in its final, cured state
must be compatible (or capable of being rendered compatible) with
the fibres of choice.
[0052] The cured resin preferably adheres to all of the types of
fibres in a particular non-woven article of the invention, thus
deterring (preferably preventing) the subsequently made non-woven
surface treating article from becoming prematurely worn during use.
In addition, cured resins suitable for use in the invention
preferably adhere to the abrasive particles so as to prevent the
particles from prematurely loosening from the non-woven surface
treating articles of the invention during use, but should allow the
presentation of new abrasive particles to the surface being
treated.
[0053] Another consideration is that the cured resin should be soft
enough to allow the non-woven surface treating articles of the
invention to be somewhat flexible during use as a polishing or
crystallisation pad so as to allow the pad to conform to
irregularities in the floor. However, the cured resin should not be
so soft as to cause undue frictional drag between the non-woven
surface treating articles of the invention and the floor being
treated. In the case of the articles of the invention being
attached to a conventional electric floor polishing machine, high
frictional drag may lead to increased amperage draw on the part of
the floor machine and may cause electrical fuses to "blow" or
circuit breakers to "trip".
[0054] Suitable resins will not readily undergo unwanted reactions,
will be stable over a wide pH and humidity ranges, and will resist
moderate oxidation and reductions. The cured resins should be
stable at higher temperatures and have a relatively long shelf
life.
[0055] The resins of the binders suitable for use in the non-woven
surface treating articles of the invention may comprise a wide
variety of resins, including synthetic polymers such as
styrene-butadiene (SBR) copolymers, carboxylated-SBR copolymers,
melamine resins, phenol-aldehyde resins, polyesters, polyamides,
polyureas, polyvinylidene chloride, polyvinyl chloride, acrylic
acid-methylmethacrylate copolymers, acetal copolymers,
polyurethanes and mixtures and cross-linked versions thereof.
[0056] One preferred group of resins useful in the present
invention, particularly if a substantial number of the fibres of
the non-woven web are polyester, are terpolymeric latex resins
formed by linear or branched copolymerisation of a mixture of a
non-functionalised mono ethylenically unsaturated co-monomer, a
functionalised mono ethylenically unsaturated co-monomer, and a
non-functionalised diethylenically unsaturated co-monomer.
("Functionalised", as used herein, means a monomer having a
reactive moiety such as --OH, NH.sub.2 COOH, and the like, wherein
"non-functionalised" means a monomer lacking such a reactive
moiety.
[0057] Particularly preferred terpolymer latex resins, used when
the fibres of the non-woven web are substantially polyester, are
formed by random or block terpolymerisation of styrene, butadiene,
and a functionalised monoethylenically unsaturated monomer selected
from the group consisting of monomers having the general formula
R.sup.1R.sup.2-C.dbd.CR.sup.3COOH and anhydrides thereof, wherein
R.sup.1 and R.sup.2 are independently selected from H and CH.sub.3
and R.sup.3 is selected from H, CH.sub.3 and COOH. In commercially
available resins of this type, the amount of functionalised
monoethylenically unsaturated monomer is typically proprietary, but
is believed to be about 1 to about 10 mole percent of the total
monomer. The mole percent of styrene ranges from about 50 percent
to about 80 percent, more preferably from about 60 to about 70
percent, particularly preferably about 65 percent, as mole
percentage of styrene and butadiene.
[0058] One commercially available and particularly preferred
terpolymer latex resin is that sold under the trade name "AMSCO RES
5900", from Unocal. This aqueous latex resin is a terpolymer of
styrene/butadiene/functionalised monoethylenically unsaturated
monomer having styrene/butadiene mole ratio of 65/35, 1 to 10 mole
percent of functionalised monoethylenically unsaturated monomer,
solids weight percent of 50, pH of 9.0, anionic particle charge,
particle size of 0.2 micrometer, and glass transition temperature
of -5.degree. C. Higher butadiene mole ratios produce a softer
resin, but at the cost of greater drag. Typically and preferred
coatable binder precursor solutions containing this latex resin and
abrasive particles which are useful in forming cured binders are
presented in Table A (wet parts by weight).
[0059] The above described terpolymers may be used uncross-linked,
but they are preferably cross-linked by the reaction of the
reactive COOH moiety with a polyfunctionalised monomer, such as a
phenolic or melamine resin, as indicated in Table A.
[0060] Cross-linking resins, as mentioned in Table A, below, may be
used to improve the water and solvent resistance of the ultimate
non-woven surface treating articles of the invention, and to
increase their firmness. Melamine-formaldehyde resins, such as the
fully methylated melamine-formaldehyde resins having low free
methyl content sold under the trade designations "Cymel 301", 1133
and 1168, "Cymel 303" and "Aerotex M-3" (all currently available
from American Cyanamid Company) and the like, are suitable. The
former provides slightly higher tensile strength while the latter
enhances stiffness and resilience of the non-woven. Phenolic resins
have also been used as cross-linking resins, such as those sold
under the trade designations "433" (Monsanto) and "R-7"
(Carborundum), and the like.
[0061] The latex resins useful in the present invention, if
cross-linked, will have greater than 10% crosslinking, usually
having in the range from about 15% to 80% cross-linking, more
usually having in the range from about 25% to 60% cross-linking,
and typically being in the range from about 45% to 55%
cross-linking. The cross-linked latex resin particles may act as
organic fillers, helping to smooth the coating of the fibres of the
non-woven webs with the linear or branched copolymers.
TABLE-US-00001 TABLE A Preferred Binder Precursor Solutions Broad
weight Preferred weight Ingredient % Range % Range SBR latex (50%
solids) 20 to 40 25 to 35 water 2 to 10 2 to 6
melamine-formaldehyde/ 1 to 10 1 to 5 crosslinking resin abrasive
10 to 65 40 to 60 catalyst (40% sol. of diammonium phosphate)
antifoam agent 0.01 to 0.05 0.01 to 0.03 surfactant 0.1 to 1.0 0.1
to 0.5
[0062] The calculated or theoretical percentage of cross-linking is
defined as the weight of polyfunctionalised monomer (or monomers)
divided by the total weight of monomers.
[0063] Non-functionalised monoethylenically unsaturated monomers
generally suitable for preparing linear, branched, and cross-linked
latex resins useful herein include, styrene, ethylvinylbenzene, and
vinyltoluene, with styrene being particularly preferred.
[0064] Diethylenically unsaturated monomers useful in the invention
include isopropene, butadiene and chloroprene, with butadiene being
particularly preferred.
[0065] If the non-woven abrasive articles comprise a substantial
amount of polyamide (e.g. nylon 6,6) fibres, other resins may be
preferred as the resin component of the binder. Examples of
suitable binders for use when the fibres comprise polyamides
include phenolic resins, aminoplast resins, urethane resins,
urea-aldehyde resins, isocyanurate resins, and mixtures thereof.
One preferred resin is a thermally curable resole phenolic resin,
such as described in Kirk-Othmer, Encyclopaedia of Chemical
Technology, 3rd Ed., John Wiley & Sons, 1981, N.Y., Vol. 17, p.
384-399, incorporated by reference herein.
[0066] Examples of commercially available phenolic resins include
those known by the trade names "VARCUM" and "DUREZ" (from
Occidental Chemicals Corp., N. Tonawanda, NY) and "AROFENE" (from
Ashland Chemical Co.). The resole phenolic resin of choice has
about 1.7:1 formaldehyde to phenol weight ratio, 76 weight percent
solids.
[0067] Other suitable binder systems are disclosed in U.S. Pat. No.
5,030,496.
[0068] Useful abrasive particles may range in size anywhere from
about 24 grade, average particle diameter of about 0.71 nm to about
1000 grade, average particle diameter of about 0.01 mm. Depending
upon the desired application, the abrasive materials used in the
article of the invention may be a soft abrasive, a hard abrasive or
a mixture thereof. Soft abrasives, having a Mohs hardness in the
range of from about 1 to 7, provide the article with a mildly
abrasive surface. Examples of useful soft abrasives include such
inorganic materials as garnet, flint, silica, pumice and calcium
carbonate; and such organic polymeric materials as polyester,
polyvinyl chloride, methacrylate, methylmethacrylate,
polymethylmethacrylate, polycarbonate and polystyrene. Hard
abrasives, those having a Mohs hardness greater than about 8,
provide the article with a more aggressive abrasive surface.
Examples of useful hard abrasives include such materials as silicon
carbide, corundum, aluminum oxide, topaz, fused alumina-zirconia,
boron nitride, tungsten carbide and silicon nitride.
[0069] The invention will be illustrated by the following
Examples.
EXAMPLES
[0070] The Examples are based on and compared with the commercially
available Scotch-Brite.RTM. product:
White Floor Pad
Red Floor Pad
Blue Floor Pad
Brown Floor Pad
Green Floor Pad
Black Floor Pad
[0071] The White, Red, Blue and Brown floor pads comprise a web of
polyester fibres. The Green and Black floor pads comprise a web of
nylon fibres. Each of these commercial products are manufactured by
impregnating the web with a slurry by roll or spray coating and
curing in an oven. The coat formulations for each product are as
follows:
White Floor Pad: SBR latex binder+talc mineral
Red Floor Pad: SBR latex binder+silica mineral+red pigment
dispersion
Blue Floor Pad: SBR latex binder+aluminium oxide (fine size)
mineral+blue pigment dispersion
Brown Floor Pad: SBR latex+aluminium oxide (fine size)+brown
pigment dispersion
Green Floor Pad: phenolic binder+calcium carbonate
filler+silica/aluminium oxide (fine size) mix of minerals+green
pigment dispersion
Black Floor Pad: phenolic binder+aluminium oxide (medium
size)+black pigment dispersion.
[0072] The following reversible floor pads in accordance with the
invention were prepared:
White/Red
White/Blue
Red/Blue
Blue/Brown
Green/Black
White/Red
[0073] A White floor pad was prepared as described above and one
surface coated with the Red floor pad coating formulation followed
by curing in an oven.
White/Blue
[0074] A White floor pad was prepared as described above and one
surface coated with the Blue floor pad coating formulation followed
by curing in an oven.
Red/Blue
[0075] A Red floor pad was prepared as described above with the
exception that the coating of the second surface was conducted
using the Blue floor pad coating formulation in place of the Red
floor pad coating formulation.
Blue/Brown
[0076] A Blue floor pad was prepared as described above with the
exception that the coating of the second surface was conducted
using the Brown floor pad coating formulation in place of the Blue
floor pad coating formulation.
Green/Black
[0077] A Green floor pad was prepared as described above and one
surface coated with the Black floor pad coating formulation
followed by curing in an oven.
[0078] The properties of the floor pad of the invention were
measured and compared with the commercial products.
Abrasive Power
[0079] The abrasive power was measured by the Schiefer Cut Test
method.
[0080] This test is a modified version of ASTM Method D 4158-82 for
determining the relative aggressiveness or the ability to retain
cut in use of Scotch-Brite.TM. materials or similar abrasive
materials. Testing produces uniform abrasion in every azimuthal
direction, not only planar or circular. The pressure used in this
test represents the average force that a slow speed rotary floor
machine puts on a floor pad. Testing procedure involves a 102 mm
acrylic plastic disc under the abrasive material at a controlled
pressure and rotation per minute (rpm) for 5,000 revolutions in a
controlled wet environment. Aggressiveness is measured by the
amount of weight (in g) removed from the plastic disc.
TABLE-US-00002 Side 1 Side 2 White floor pad 0 0 Red floor pad 0.1
0.1 Blue floor pad 1 1 Green floor pad 1.2 1.2 Brown floor pad 2.3
2.3 Black floor pad 3.2 3.2 White/Red 0 0.1 White/Blue 0 1 Red/Blue
0.1 1 Blue/Brown 1 2.3 Green/Black 1.2 3.2
[0081] It will be seen that the Red, Blue, Brown and Black surfaces
of the floor pad of the invention behave in the same manner as
their counterpart commercial products.
Tensile Strength
[0082] Samples 51 mm (2 inches) wide and 150 nm long were cut and
tested on a Lhomargt dynamometer at a speed of 305 mm per minute.
The average of six measurements was recorded. TABLE-US-00003 Sample
N/2 inches Sample N/2 inches White 35 White/Red 35 Red 37 Red/Blue
37 Blue 37 Blue/Brown 37 Green 38 Green/Black 38
Performance Tests a) Shine at Buffing
[0083] A floor tile was coated with a floor finish. It was dulled
with an abrasive hand pad and the gloss is measured with a gloss
meter.
[0084] The pad under investigation was mounted on a polishing
machine rotating at 400 RPM. The pad was run onto the tile with a
fixed number of passes, generally six and twelve passes.
[0085] White and White/Red on the White side performed equally.
[0086] Red and Red/Blue on the Red side performed equally.
b) Shine at Spray Buffings
[0087] A floor tile was coated with a floor finish. It was dulled
with an abrasive hand pad and the gloss measured with a gloss
meter.
[0088] The pad under investigation was mounted on a polishing
machine rotating at 400 RPM. A few sprays of a commercially
available "spray buff cleaner and polish" liquid were sprayed onto
the tile. The pad was run six times over the tile and the gloss
measured.
[0089] A few sprays of "spray buff cleaner and polish" were again
applied onto the tile and the pad run over the tile for six more
passes. The gloss was again measured.
[0090] Red and White/Red on the Red side performed equally.
[0091] Blue and Red/Blue on the Blue side performed equally.
[0092] Blue and Blue/Brown on the Blue side performed equally.
d) Cleaning
[0093] A black mark was applied onto a floor tile. One coat of
floor finish was applied onto the mark. The pad under investigation
was mounted on a polishing machine rotating at 150 RPM. The number
of passes required to remove the coat of floor finish and the mark,
in wet conditions was measured.
[0094] Red and Red/Blue on the Blue side performed equally.
[0095] Blue and Blue/Brown on the Blue side performed equally.
[0096] Green and Green/Black on the Green side performed
equally.
Stripping or Heavy Duty Cleaning
[0097] A black mark was applied onto a floor tile. Three coats of
floor finish were applied onto the mark. The pad under
investigation was mounted on a polishing machine rotating at 150
RPM. The number of passes required to remove the coats of floor
finish and the mark, in wet conditions, was measured.
[0098] Brown and Blue/Brown on the Brown side performed
equally.
[0099] Green and Green/Black on the Black side performed
equally.
* * * * *