U.S. patent application number 11/179450 was filed with the patent office on 2006-01-12 for cleaning implement comprising a layer of melamine foam.
This patent application is currently assigned to The Procter & Gamble Company. Invention is credited to Gary Ashe, Alan Scott Goldstein.
Application Number | 20060005338 11/179450 |
Document ID | / |
Family ID | 35169882 |
Filed Date | 2006-01-12 |
United States Patent
Application |
20060005338 |
Kind Code |
A1 |
Ashe; Gary ; et al. |
January 12, 2006 |
Cleaning implement comprising a layer of melamine foam
Abstract
A cleaning implement comprising a layer of melamine foam, having
a thickness of at least 15 mm, and a layer of a second foam having
a water-absorbency of at least 0.35 g of water per cm.sup.3 of said
second foam.
Inventors: |
Ashe; Gary; (Buffalo,
NY) ; Goldstein; Alan Scott; (Blue Ash, OH) |
Correspondence
Address: |
THE PROCTER & GAMBLE COMPANY;INTELLECTUAL PROPERTY DIVISION
WINTON HILL TECHNICAL CENTER - BOX 161
6110 CENTER HILL AVENUE
CINCINNATI
OH
45224
US
|
Assignee: |
The Procter & Gamble
Company
|
Family ID: |
35169882 |
Appl. No.: |
11/179450 |
Filed: |
July 12, 2005 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60587070 |
Jul 12, 2004 |
|
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|
Current U.S.
Class: |
15/244.4 ;
134/6 |
Current CPC
Class: |
B32B 7/08 20130101; B32B
2307/728 20130101; C11D 17/049 20130101; B32B 2307/31 20130101;
A47L 17/08 20130101; B32B 5/18 20130101; B32B 2266/0285 20130101;
B32B 2250/02 20130101; B32B 2266/025 20130101; B32B 2432/00
20130101; B32B 5/32 20130101; A47L 13/16 20130101; B32B 2307/726
20130101; B32B 7/02 20130101; B32B 2250/22 20130101; B32B 2266/0278
20130101 |
Class at
Publication: |
015/244.4 ;
134/006 |
International
Class: |
A47L 13/16 20060101
A47L013/16 |
Claims
1. A cleaning implement (1) comprising a layer of melamine foam
(2), having a thickness of at least 15 mm, and a layer of a second
foam (3) having a water-absorbency of at least 0.35 g of water per
cm.sup.3 of said second foam.
2. The cleaning implement (1) of claim 1, having a shape selected
from: cube shape, rectangular shape, pyramid shape, cylindrical
shape, cone shape, pencil eraser shape, cuboid shape, and
tetrahedron shape.
3. The cleaning implement (1) of claim 1, having a volume of from 1
cm.sup.3 to 10,000 cm.sup.3.
4. The cleaning implement (1) of claim 1, wherein said layer of
melamine foam (2) and said layer of a second foam (3) are joined by
means of a permanent attachment or a temporary attachment.
5. The cleaning implement (1) of claim 1, wherein said layer of
melamine foam (2) and said layer of a second foam (3) are joined by
an attachment means providing a permanent attachment selected from:
foam flame laminating the two layers together; use of a permanent
adhesive; sewing the two layers together; and needle-punching the
two layers together; and combinations thereof.
6. The cleaning implement (1) of claim 5, wherein said layers are
joined together by foam flame lamination.
7. The cleaning implement (1) of claim 1, wherein the ratio of said
melamine foam (2) to said second foam is from 20:1 to 1:20 by
volume.
8. The cleaning implement (1) of claim 1, wherein the thickness of
the melamine foam (2) layer is from 15 mm to 100 mm.
9. The cleaning implement (1) of claim 1, wherein said melamine
foam (2) is a melamine-formaldehyde resin foam.
10. The cleaning implement (1) of claim 1, wherein said second foam
(3) has a water-absorbency of at least 0.4 g of water per cm.sup.3
of said second foam.
11. The cleaning implement (1) of claim 1, wherein said second foam
(3) is selected from the group of foams having a water-absorbency
of at least 0.35 g of water per cm.sup.3 of said second foam and
consisting of: polyurethane foams; polypropylene foams;
polyethylene foams; cellulose foam sponges; naturally occurring
sponges; open-cell polyester foams; and cross-lined polyethylene
foams; and combinations thereof.
12. The cleaning implement (1) of claim 11, wherein said second
foam (3) is a polyurethane foam having a water-absorbency of at
least 0.35 g of water per cm.sup.3 of said second foam.
13. The cleaning implement (1) of claim 11, wherein said second
foam is a hydrophilic ester polyurethane foam.
14. The cleaning implement (1) of claim 1, wherein said layer of a
second foam (3) has a total water absorbency of at least 10 g of
water.
15. A cleaning implement (1) comprising a layer of melamine foam
(2), having a thickness of at least 15 mm, and a layer of a second
foam (3), wherein the layers are joined together by foam flame
lamination.
16. A method of cleaning a hard surface comprising bringing a
cleaning implement according to claim 1, into contact with said
hard surface.
17. The method of cleaning a hard surface of claim 16, wherein said
method additionally comprises wetting said cleaning implement (1)
with an appropriate solvent prior to bringing said cleaning
implement into contact with said hard surface.
18. The method of cleaning a hard surface of claim 17, wherein said
appropriate solvent comprises water.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of the filing date U.S.
Provisional Application Ser. No. 60/587,070 filed Jul. 12, 2004,
the disclosure of which is incorporated by reference herein.
TECHNICAL FIELD
[0002] The present invention relates to a cleaning implement
comprising a layer of melamine foam and a layer of a second
foam.
BACKGROUND OF THE INVENTION
[0003] Melamine-formaldehyde resin foams, also referred to herein
as melamine foams, are well known in the art for use in industrial
applications, for example, as heat or sound insulating materials as
well as for fire protection purposes. Indeed, in the automotive
industry, melamine foam is commonly used to insulate motor
compartments and driver cabins of cars and trucks.
[0004] Recently, a novel application for such melamine foams in the
area of hard surface cleaning has been discovered. Indeed, cleaning
implements of cut or molded pieces of melamine foam have become
popular to remove soils and/or stains from hard surfaces (i.e.,
cleaning of hard surfaces) such as tiles, walls, floors, sanitary
fittings such as sinks, showers, shower curtains, wash basins, WCs,
household appliances including, but not limited to, refrigerators,
freezers, washing machines, automatic dryers, ovens, microwave
ovens, dishwashers and so on. Indeed, melamine foam sponges are
currently marketed under the tradename Mr. Clean Magic Eraser.RTM..
In order to stabilise the melamine foam and to prevent early
break-up of it, sponges combining melamine foam and a stabilising
material, such as a rigid polyurethane have been proposed and
marketed (sold under the tradename Scotch Brite Easy Erasing
Pad.RTM. by 3M Corp.). Melamine foam pieces combined with or
laminated to a second material are known in the art, for example,
from U.S. 2001/0024720 or JP 2001-258809.
[0005] It is has been observed that melamine foam shows an
excellent soil and/or stain removal performance when used to clean
hard surfaces. Indeed, it has been observed that melamine foam when
wetted with an appropriate solvent, such as tap water, removes
soils and/or stains from a hard surface when said hard surface is
brought into contacted with said wetted melamine foam. By "bringing
into contact" it is meant wiping, swiping, rubbing or the like. In
order for the melamine foam to optimally remove soils and/or stains
from hard surfaces substantial amounts of an appropriate solvent,
such as tap water, have to be used. Most commonly, tap water is
used by the users of melamine foam when removing soils and/or
stains from hard surfaces. When used with water or any other
appropriate solvent, the melamine foam comes off as small particles
(meaning, the foam crumbles) when brought into contact with a hard
surface. Indeed, a milky suspension of small melamine foam
particles in water is formed.
[0006] It has been discovered by consumer research that users of
melamine foams, when removing soils and/or stains from hard
surfaces, are looking for a way to absorb excessive amounts of
water that have been used as well as the milky suspension of small
melamine foam particles in water. Although the melamine foam itself
is capable of absorbing water and/or milky melamine-water
suspension, the absorbance of water and/or milky melamine-water
suspension by the melamine foam is regarded as not sufficient by
the users. The same applies to the currently marketed sponges
combining melamine foam and a stabilising material, as the
stabilising material therein alone or in combination with the
melamine foam is not capable of absorbing sufficient amounts of
water and/or milky melamine-water suspension. Furthermore, it is
inconvenient for a user of melamine foams, when removing soils
and/or stains from hard surfaces, to use a separate absorbent
utensil, like an absorbent paper towel, a sponge or a cloth, in
addition to the melamine foam to absorb excessive amounts of water
that has been used as well as the formed milky melamine-water
suspension.
[0007] It is therefore, an objective of the present invention to
provide a cleaning implement based on a melamine foam, wherein said
implement is capable of absorbing excessive amounts of water (or
another appropriate solvent) that have been used as well as the
milky melamine-water suspension (i.e., milky suspension of small
melamine foam particles in water (solvent)) generated upon use.
[0008] It has now been found that the above objective can be met by
a cleaning implement comprising a layer of melamine foam, having a
thickness of at least 15 mm, and a layer of a second foam having a
water-absorbency of at least 0.35 g of water per cm.sup.3 of said
second foam.
[0009] Advantageously, by having a thickness of at least 15 mm of
the layer of melamine foam in the cleaning implement of the present
invention, the amount of melamine foam provided is sufficient
material for an acceptable number of cleaning operations (i.e., the
removal of soils and/or stains from hard surfaces).
[0010] Another advantage of the cleaning implement herein is that
the second foam not only absorbs the excessive amounts of water
that have been used as well as the milky melamine-water suspension
but also provides stability to the cleaning implement. Indeed, it
has been found that non-stabilised melamine foam is prone to
breakage or puncturing when used to remove soils and/or stains from
hard surfaces due to its relative fragility as well as the user's
uneven pressure when bringing it into contact with the hard
surfaces to be cleaned.
SUMMARY OF THE INVENTION
[0011] The present invention encompasses a cleaning implement
comprising a layer of melamine foam, having a thickness of at least
15 mm, and a layer of a second foam having a water-absorbency of at
least 0.35 g of water per cm.sup.3 of said second foam.
[0012] The present invention further encompasses a cleaning
implement comprising a layer of melamine foam, having a thickness
of at least 15 mm, and a layer of a second foam, wherein the layers
are joined together by foam flame lamination.
[0013] The present invention further encompasses a method of
cleaning a hard surface by bringing a cleaning implement according
to the present invention into contact with said hard surface,
preferably wherein said cleaning implement has been wetted with an
appropriate solvent (tap water) prior to bringing said cleaning
implement into contact with said hard surface.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] FIG. 1 is a perspective view of a cleaning implement
according to the present invention.
[0015] FIG. 2 is a top view thereof.
[0016] FIG. 3 is a bottom view thereof.
[0017] FIG. 4 is a side elevation view thereof (the opposite side
view being the same).
[0018] FIG. 5 is an end view thereof (the opposite side view being
the same).
[0019] FIG. 6 is a perspective view of a cleaning implement
according to the present invention featuring the Mr. Clean.RTM.
Head logo.
DESCRIPTION OF THE REFERENCE NUMERALS
[0020] 1: Cleaning implement [0021] 2: Melamine foam layer [0022]
3: Layer of a second foam having a water-absorbency of at least
0.35 g of water per cm.sup.3 of said second foam [0023] 4: Line
indicating the separation of the melamine foam layer and said
second foam. [0024] 5: Mr. Clean.RTM. Head logo.
DETAILED DESCRIPTION OF THE INVENTION
[0024] Cleaning Implement
[0025] The cleaning implement (1) herein comprises at least two
separate layers. A first layer of melamine foam (2), having a
thickness of at least 15 mm, and a second layer of a second foam
(3) having a water-absorbency of at least 0.35 g of water per
cm.sup.3 of said second foam.
[0026] By a "cleaning implement" it is meant herein an article of
manufacture of any suitable shape and/or size and/or volume
suitable for cleaning, i.e., removing spots and/ore stains from,
hard surfaces. In a highly preferred embodiment according to the
present invention, the cleaning implement herein is in a shape
and/or size and/or volume suitable for use by a consumer to clean
hard surfaces therewith.
[0027] The layers of melamine foam and second foam may be arranged
in said cleaning implement in any way suitable. In a preferred
embodiment the layers of melamine foam and second foam are arranged
parallel to at least one side, preferably two opposite sides, of
the cleaning implement. However, the cleaning implement may also
have an irregular shape. Indeed, the thickness of the layers may be
constant or vary throughout the cleaning implement. The separation
line (4) between the two layers may form a straight line or may
form a bend or be completely irregular. In addition, the separation
plane of the layers may be in the center of cleaning implement,
dividing the implement in two equal parts, or may be in the upper
or lower part of the implement. In addition, the cleaning implement
may be in the shape of a sphere or a globule or an ellipsoid with
the separation plane of the layers forming a spherical segment or
one of the layers, preferably the layer of a second foam here,
forming a sphere in a sphere (similar to the layers of an
onion).
[0028] Suitable shapes of the cleaning implements herein may be
selected from the group consisting of: cube shape, rectangular
shape, pyramid shape, cylindrical shape, cone shape, pencil eraser
shape, cuboid shape, tetrahedron shape; sphere shape; globular
shape; and ellipsoid shape. Preferably, said cleaning implement has
a shape selected from the group consisting of: cube shape,
rectangular shape, pencil eraser shape, and cuboid shape.
[0029] Suitable volumes of the cleaning implements herein may be
from 1 cm.sup.3 to 10,000 cm.sup.3, preferably from 10 cm.sup.3 to
1,000 cm.sup.3, more preferably from 150 cm.sup.3 to 250
cm.sup.3.
[0030] In a highly preferred embodiment herein, the cleaning
implement (1) herein has a cuboid shape defined by three groups of
parallel and equal length sides, referred to as a, b and c, wherein
a ranges from 2 cm to 20 cm, preferably 4 cm to 8 cm, b ranges from
2 cm to 20 cm preferably 8 cm to 15 cm, and c ranges from 1.5 cm to
5 cm, preferably 2 cm to 4 cm.
[0031] In this highly preferred embodiment, wherein the cleaning
implement (1) herein has a cuboid shape, the line indicating the
separation (4) of the two layers (or the surface areas where the
two layers are joined together) of the implement is preferably
substantially parallel (preferably parallel) to the side of the
cuboid shaped implement having the largest surface area (as shown
in FIGS. 1-5).
[0032] In another highly preferred embodiment herein the cleaning
implement herein is in the shape of a pencil eraser. By "shape of a
pencil eraser" it is meant herein a voluminous body having six
walls, wherein three pairs of parallel and equally shaped and sized
walls exist and wherein one pair of walls are in the shape of a
parallelogram and the remaining two pairs of walls are of
rectangular shape. In this preferred embodiment, wherein the
cleaning implement herein has the shape of a pencil eraser, the
line indicating the separation of the two layers (or the surface
areas where the two layers are joined together) of the implement is
preferably substantially parallel (preferably parallel) to the side
of implement in the shape of a pencil eraser having the largest
surface area.
[0033] In order to obtain suitable cleaning implements according to
the present invention, the melamine foam layer and the second layer
of a second foam having a water-absorbency of at least 0.35 g of
water per cm.sup.3 of said second foam have to be attached to each
other. This attachment can be achieved by any attachment means
suitable for joining the two layers. The attachment may be either a
permanent attachment (wherein the two layers cannot be separated
without inflicting substantial damage to the layers) or temporary
attachment (wherein the two layers may be separated without
inflicting substantial damage to the layers). Suitable attachment
means providing a permanent attachment are selected from the group
consisting of: foam flame laminating the two layers together; use
of a permanent adhesive; sewing the two layers together; and
needle-punching the two layers together; and combinations thereof.
Suitable attachment means providing a temporary attachment are
selected from the group consisting of: a weak adhesive; Velcro; and
a water-based, water-soluble coating or adhesive; and combinations
thereof.
[0034] In a preferred embodiment here, the attachment of layers
herein is a permanent attachment. Even more preferably, the layers
are joined together by foam flame lamination.
[0035] Foam flame lamination is a continuous process that can
adhere foams and additional materials, if any, to one or both sides
of a foam in a single pass. The process of flame lamination
involves the passing of a first foam (either the melamine foam
herein or the second foam herein) over an open flame, which creates
a thin layer of molten foam/polymer. A second foam (either the
second foam herein or the melamine foam herein, depending on the
first step) is pressed against the first foam while it is still in
the molten state. Foams and additional material, if any, can be
adhered to one or both sides of the foam in a single pass.
Furthermore, additional passes are optional. The strength of the
bond depends upon the foams and additional material, if any,
selected and the processing conditions (i.e., gas type, flame
height and spread, foam burn-off and nip pressure).
[0036] Indeed, it has been found that the cleaning implement
according to the present invention wherein the melamine foam layer
and the layer of a second foam having a water-absorbency of at
least 0.35 g of water per cm.sup.3 of said second foam are joined
together by foam flame lamination as compared to the use of an
adhesive, show no hard bond line from the adhesive at the interface
between the two layers. Furthermore, no additional chemicals (such
as adhesives) are added to the cleaning implement, which may
redeposit on the hard surface to be cleaned when the melamine foam
layer has worn off.
[0037] In view thereof, the present invention further encompasses
as an independent embodiment a cleaning implement (1) comprising a
layer of melamine foam (2), having a thickness of at least 15 mm,
and a layer of a second foam (2), wherein the layers are joined
together by foam flame lamination.
[0038] The cleaning implement according to the present invention
comprises at least two separate layers as described herein. The
cleaning implement may contain more than two layers, wherein said
additional layers, if, any, may be of the same or similar materials
as the melamine foam or said second foam, or may be made of another
material having similar properties as said second foam or different
properties therefrom. Indeed, the cleaning implement herein may be
in a so-called sandwich configuration, wherein three layers are
present. In a preferred embodiment, wherein the cleaning implement
herein is in a sandwich configuration, the middle layer may be said
second foam and at least one of the two outer layers is a melamine
foam with the second outer layer being either a melamine foam or
another material providing other feature, such as abrasiveness or
increased rigidity.
[0039] The layers of the cleaning implement according to the
present invention may cover each other either partially or fully.
By a "partial coverage" it is meant that at least one of the layers
overlaps the other layer (or other layers, if any) and is not fully
covered by said other layer (or other layers, if any). By a "full
coverage" it is meant that the layers of the cleaning implement do
fully cover each other and that none of the layers substantially
overlap the other layer (or other layers, if any).
[0040] The ratio of said melamine foam to said second foam in the
cleaning implement according to the present invention is preferably
from 20:1 to 1:20 by volume, more preferable from 10:1 to 1:10 by
volume, even more preferably 5:1 to 1:1, still more preferably 5:1
to 2:1, and most preferably from 4:1 to 3:1 by volume.
[0041] In order to obtain suitable cleaning implements according to
the present invention, the melamine foam- and second foam-raw
materials may have to be modified in shape and/or size. This
modification can be done by any means known to those skilled in the
art. Suitable means of modifying the shape and/or size of melamine
foam- and second foam-raw materials may be selected from the group
consisting of: compression, heat-compression, cutting, breaking,
and tearing, and combinations thereof.
[0042] The cleaning implement herein may be modified or
post-processed. In particular, such modification and/or
post-processing of the cleaning implement may be used to associate
a brand-name and/or logo of a hard surface cleaner with said
cleaning implement. Suitable modification and/or post-processing of
the cleaning implement may be printing on one or several sides of
said cleaning implement, and/or embossing of one or several sides
of said cleaning implement using heat and/or pressure, and
combinations thereof. A cleaning implement modified in order to
associate a logo of a hard surface cleaner (Mr. Clean.RTM. head
logo) with said cleaning implement is shown in FIG. 6, wherein said
logo of a hard surface cleaner (Mr. Clean.RTM. head logo (5)) has
been embossed or printed onto said second foam.
Melamine Foam
[0043] The cleaning implement (1) herein comprises a layer of
melamine foam (2), having a thickness of at least 15 mm.
[0044] By "melamine foam" it is meant herein a
melamine-formaldehyde resin foam. By "thickness" it is meant
herein, the length in mm of the side having the smallest extension
compared to other sides of the melamine foam layer (the height of
the melamine foam layer). In case the cleaning implement is based
on a rectangular shape and the melamine foam layer extends in
parallel to the sides of the shape having the largest surface area
(extensions in the x and y axis), the thickness can be referred to
as the extension in the direction of the y axis. In case the
cleaning implement is based on an irregular shape and/or the
extension of the thickness of the melamine foam layer varies (i.e.,
the layer is thicker in some parts of the implement as compared to
others), it is sufficient that at least once the thickness of the
melamine foam layer extends over the thickness required herein.
[0045] The thickness of the melamine foam layer herein is at least
15 mm, preferably from 15 mm to 100 mm, more preferably from 17 mm
to 50 mm, even more preferably from 20 mm to 40 mm, and most
preferably from 21 mm to 25 mm.
[0046] The total volume of said layer of melamine foam in the
cleaning implement herein is preferably from 50 cm.sup.3 to 400
cm.sup.3, more preferably from 80 cm.sup.3 to 300 cm.sup.3, even
more preferably from 150 cm.sup.3 to 275 cm.sup.3, and most
preferably from 200 cm.sup.3 to 250 cm.sup.3.
[0047] A suitable melamine-formaldehyde resin foam raw material is
commercially available under the trade name Basotect.RTM. from
BASF.
[0048] The "melamine foam" described above can be prepared by
blending major starting materials of melamine and formaldehyde, or
a precursor thereof, with a blowing agent, a catalyst and an
emulsifier, injecting the resultant mixture into a mold, and making
the reaction mixture generate heat through a proper means such as
heating or irradiation with electromagnetic wave to cause foaming
and curing. The molar ratio of melamine to formaldehyde (i.e.,
melamine:formaldehyde) for producing the precursor is preferably
1:1.5 to 1:4, particularly preferably 1:2 to 1:3.5 in
melamine:formaldehyde. In addition, number average molecular weight
of the precursor is preferably 200 to 1,000, particularly
preferably 200 to 400. Additionally, formalin, which is an aqueous
solution of formaldehyde, is usually used as formaldehyde.
[0049] As monomers for producing the precursor, the following
various monomers may be used in an amount of 50 parts by weight
(hereinafter abbreviated as "parts") or less, particularly 20 parts
by weight or less, per 100 parts by weight of the sum of melamine
and formaldehyde in addition to melamine and formaldehyde. As other
monomers corresponding to melamine, there may be used C1-5
alkyl-substituted melamines such as methylolmelamine,
methylmethylolmelamine and methylbutylolmelamine, urea, urethane,
carbonic acid amides, dicyandiamide, guanidine, sulfurylamides,
sulphonic acid amides, aliphatic amines, phenols and the
derivatives thereof. As aldehydes, there may be used acetaldehyde,
trimethylol acetaldehyde, acrolein, benzaldehyde, furfurol,
glyoxal, phthalaldehyde, terephthalaldehyde, etc.
[0050] As the blowing agent, there may be used pentane,
trichlorofluoromethane, trichlorotrifluoroethane, etc. However, use
of so-called fleons.RTM. such as trichlorofluoromethane is
regulated from the point of view of environmental problems, thus
not being preferred. On the other hand, pentane is preferred in
that it easily provides a foam when used even in a small amount
but, since it has a volatile flammability, it requires sufficient
care in its handling. Further, as the catalyst, formic acid is
commonly used and, as the emulsifier, anionic surfactants such as
sodium sulfonate may be used.
[0051] The amount of the electromagnetic wave to be irradiated for
accelerating the curing reaction of the reaction mixtures is
preferably adjusted to be 500 to 1,000 kW, particularly 600 to 800
kW, in electric power consumption based on 1 kg of an aqueous
formaldehyde solution charged in the mold. In case when this
electric power consumption is insufficient, there results an
insufficient foaming, leading to production of a cured product with
a high density. On the other hand, in case when the electric power
consumption is excessive, the pressure upon foaming becomes
seriously high, leading to serious exhaustion of the mold and even
the possibility of explosion. Thus, electric power consumption
outside the range is not preferred.
Second Foam
[0052] The cleaning implement (1) herein also comprises a layer of
a second foam (3) having a water-absorbency of at least 0.35 g of
water per cm.sup.3 of said second foam.
[0053] Preferably, said second foam has a water-absorbency of at
least 0.4 g, more preferably at least 0.45 g, even more preferably
at least 0.5 g, still more preferable at least 0.55 g and most
preferably at least 0.575 g of water per cm.sup.3 of said second
foam.
[0054] The total water absorbency of the layer of a second foam is
preferably at least 10 g of water, preferably at least 11 g of
water, more preferably at least 13 g of water and most preferably
at least 15 g of water.
[0055] Any foam material suitable to provide the water-absorbency
required herein may be used as said second foam.
[0056] Suitable second foams for use herein are selected from the
group of foams having the required water-absorbency and consisting
of: polyurethane foams; polypropylene foams; polyethylene foams;
cellulose foam sponges; naturally occurring sponges; open-cell
polyester foams; and cross-lined polyethylene foams; and
combinations thereof.
[0057] In a preferred embodiment herein, the second foam is a
polyurethane foam having a water-absorbency of at least 0.35 g of
water per cm.sup.3 of said second foam. Polyurethane foams are
generally prepared by the reaction of an active hydrogen-containing
compound (i.e., a polyol) and a polyisocyanate, in the presence of
a blowing agent such as water, and usually a reaction catalyst and
foam stabilizer.
[0058] In a highly preferred embodiment herein, the second foam is
a hydrophilic ester polyurethane foam. A suitable hydrophilic ester
polyurethane foam is commercially available under the tradename
Cellulex.RTM. from Foamex L.P. Hydrophilic ester polyurethane foams
and their preparation is described in U.S. Pat. No. 6,756,416. Such
hydrophilic ester polyurethane foam does not swell appreciably upon
absorbing and retaining liquids. By a "hydrophilic ester
polyurethane foam" it is meant a ester polyurethane foam capable of
absorbing liquids, such as water, in sufficient amounts.
[0059] The preparation of hydrophilic ester polyurethane foam as
described in U.S. Pat. No. 6,756,416 is by: a) forming a
polyurethane foam by mixing together the following components: 100
parts by weight of an ester polyol; from 20.0 to 62.0 parts by
weight, based on 100 parts polyol, of an isocyanate, wherein the
isocyanate index is 110 or less; and from 1.0 to 3.0 parts by
weight, based on 100 parts polyol, of a stabilizing surfactant; and
b) treating the polyurethane foam in a caustic bath to form the
hydrophilic ester polyurethane foam The hydrophilic ester
polyurethane foams described in U.S. Pat. No. 6,756,416 have a
water absorption rate of at least 0.32 g of water per cm.sup.3 of
foam (20 pounds of water per square foot).
[0060] The water-absorbency by cm.sup.3 of a foam material can be
measured by: The dimensions (length.times.width.times.height), of a
sample of the foam material is measured in "cm" to determine the
volume (cm.sup.3) of material used for the test. The initial weight
of the sample is measured and recorded in grams. The sample is
submerged in water and then is squeezed out by hand until no
additional water drips out. The sample is then weighed again and
the weight is recorded (grams). This weight is considered the tare
weight. The sample is then allowed to soak in a tub of water for 1
minute. The sample is removed from the tub after 1 minute, and hung
vertically to allow excess water to drip for 5 minutes. The sample
is then weighed and recorded in grams (wet sample weight). The
sample is squeezed out by hand and weighed until tare weight is
achieved. For each sample the steps of soaking, dripping off,
weighing and squeezing are repeated three times. For each foam
material the above measurements are repeated with at least 12
samples. For each sample the total amount of water absorbed is
calculated by subtracting the tare weight from wet sample weight.
To calculate the water-absorbency by cm.sup.3 of a sample the total
amount of water absorbed in grams, is divided by the total volume
of the sample. To calculate the water-absorbency by cm.sup.3 of a
foam material the calculated water-absorbency by cm.sup.3 of each
of its samples is averaged.
[0061] The total water-absorbency a foam layer can be measured by:
The dimensions (length.times.width.times.height), of the foam layer
is measured in "cm" to determine the volume (cm.sup.3) of material
used for the test. The initial weight of the foam layer is measured
and recorded in grams. The foam layer is submerged in water and
then is squeezed out by hand until no additional water drips out.
The foam layer is then weighed again and the weight is recorded
(grams). This weight is considered the tare weight. The foam layer
is then allowed to soak in a tub of water for 1 minute. The foam
layer is removed from the tub after 1 minute, and hung vertically
to allow excess water to drip for 5 minutes. The foam layer is then
weighed and recorded in grams (wet foam layer weight). The foam
layer is squeezed out by hand and weighed until tare weight is
achieved. For each foam layer the steps of soaking, dripping off,
weighing and squeezing are repeated three times. For each foam
layer the above measurements are repeated with at least 12 samples.
For each foam layer the total amount of water absorbed is
calculated by subtracting the tare weight from wet sample weight
and the results are averaged for the described repetitions.
[0062] The above measurements are performed at room temperature and
normal humidity conditions and the measurements are performed with
normal tap water.
[0063] The thickness of said layer of a second foam is preferably
up to 30 mm, preferably from 0.5 mm to 20 mm, more preferably from
1 mm to 15 mm, even more preferably from 2 mm to 10 mm, and most
preferably from 4 mm to 8 mm.
[0064] The total volume of said layer of a second foam having a
water-absorbency of at least 0.35 g of water per cm.sup.3 of said
second foam in the cleaning implement herein preferably from 10
cm.sup.3 to 100 cm.sup.3, more preferably from 20 cm.sup.3 to 70
cm.sup.3, even more preferably from 30 cm.sup.3 to 60 cm.sup.3, and
most preferably from 40 cm.sup.3 to 50 cm.sup.3.
[0065] In a preferred embodiment, said a layer of a second foam
having a water-absorbency of at least 0.35 g of water per cm.sup.3
of said second foam is made of a material other than melamine
foam.
Additional Material
[0066] The cleaning implement may contain more than two layers,
wherein said additional layers, if, any, may be of a material
(additional material) other than said melamine foam and said second
foam. The additional material may be suitable to provide beneficial
features to the cleaning implement, such as abrasiveness or
increased rigidity or increased grip.
[0067] In view thereof, said additional material may be a scouring
material or a scouring pad, a rigid foam material, a handle made of
thermoplastic material, wood, metal or combinations thereof, and
the like.
Packaging Means
[0068] The cleaning implement herein may be combined in an article
of manufacture with a packaging means.
[0069] The packaging means herein may be any suitable means known
to package cleaning implements. Indeed, particularly suitable
packaging means herein are selected from the group consisting of:
paper bags, plastic bags, cartons, carton boxes, flow wraps,
plastic wraps, and paper wraps, and the like and combinations
thereof.
[0070] The packaging means herein may be printed and/or modified.
In particular, such printing and/or other modification may be used
to associate a brand-name and/or logo of a hard surface cleaner
with said cleaning implement.
Method of Cleaning a Hard Surface
[0071] In another embodiment the present invention encompasses a
method of cleaning a hard surface by bringing a cleaning implement
according to the present invention into contact with said hard
surface. By "cleaning" it is meant herein removing spots and/or
stains from hard surfaces.
[0072] Suitable hard surfaces herein are tiles, walls, floors,
sanitary fittings such as sinks, showers, shower curtains, wash
basins, WCs, household appliances including, but not limited to,
refrigerators, freezers, washing machines, automatic dryers, ovens,
microwave ovens, dishwashers and so on.
[0073] The method of cleaning a hard surface according to the
present invention may additionally include the step of wetting said
cleaning implement with an appropriate solvent, preferably tap
water, prior to bringing said cleaning implement into contact with
said hard surface.
[0074] While particular embodiments of the present invention have
been illustrated and described, it would be obvious to those
skilled in the art that various other changes and modifications can
be made without departing from the spirit and scope of the
invention. It is therefore intended to cover in the appended claims
all such changes and modifications that are within the scope of
this invention.
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