[0001] The present invention relates to articles having an antimicrobial benefit. More particularly
the present invention relates to hydrophilic foam articles having an antimicrobial
benefit.
[0002] Cleaning articles are notoriously old to the art. Popular cleaning articles which
are known include, for example sponges, wiping articles, clothes, rags, disposable
paper towels, and the like. Generally, these articles may be used with or without
the addition of a cleaning composition in order to locally treat a stained surface.
Very often, such a cleaning composition includes one or more detersive surfactants,
and optionally may contain are frequently used with cleaning articles. Such products
are widely known and used. In use, a consumer sprays, pours, or otherwise applies
a useful quantity of such a cleaning composition to a surface usually in the locus
of a soiled or stained hard surface, and then using the cleaning article to wipe the
surface and thereby remove soils or stains from the surface. Generally thereafter,
the cleaning article can be reused, or may optionally be disposed of.
[0003] An inherent problem with cleaning articles which are used a number of times is that,
very frequently they provide a breeding ground for undesirable bacteria and other
microorganisms. Such include gram positive microorganisms as well as gram negative
microorganisms. Thus, quite inadvertently, the cleaning article indeed may be an incubator
for such undesired microorganisms. Generally, such cleaning articles are maintained
in a moist state at a generally room temperature (approx. 20°C) environment, such
typically are also suitable conditions for maintaining the viability of such microorganism.
Worse, when left unattended for some time the growth of the undesired micro-organisms
increases the amount of these microorganisms which may come into contact with both
the user, and with the surface to be treated upon the next use of the cleaning article.
[0004] The prior art has proposed various methods for controlling the growth of undesired
microorganisms in cleaning articles, and in particular sponges. Foam sponges are very
popular and are in wide spread use, typically are based on either regenerated cellulose,
or based on one or more of a variety of foamed polymers such as foamed polyurethane.
Natural sponges are also notoriously old, and are widely used as cleaning articles.
A more modern approach to controlling the growth of undesirable microorganism is for
example described in
US Patent 6228389 which describes a sponge, especially a regenerated cellulose sponge which is provided
with a low aqueous soluble biocidal composition. The low aqueous solubility provides
an extended antimicrobial activity to the sponge, particularly between uses. A further
sponge is described in
US Patent 6287584 wherein a sponge, such as a regenerated cellulose sponge is injected with a carrier
mass which is sparingly water soluble, and where in such carrier mass incorporates
a bias sign. The low aqueous viability of the carrier mass acts to provide a controlled
release of the biocide into the interior of the sponge particularly when the sponge
is maintained in a moist condition between uses. The articles described in
US Patent 6375964 B1 disclose foamed hydrophobic closed celled articles which include a support material
as a source for the controlled release of silver ions, which silver ions provide a
disinfecting effect to a treated surface. Certain hydrophilic foam sponge articles
are described in
US 4476251 which foam is prepared by mixing together a select prepolymer reactant and water,
and adding to the mixture prior to foam formation a nonionic surfactant, a quaternary
ammonium compound and a silicon-based surfactant.
US Patent 5091102 describes a substantially flexible dry matrix and the result and article capable
of cleaning a surface by removing dust and/or organic film and rendering the surface
substantially static-free, suitable for use as a garment, air filter or mat, wherein
the dry matrix is uniformly coated with an amount of treatment solution sufficient
to allow the matrix to retain its substantially dry characteristics, said treatment
solution comprising between about 25% and 75% of at least one glycol compound, between
about 0.2% and 60% of a cationic surfactant, an antimicrobial compound and optionally
up to about 45% of a nonionic surfactant.
US Patent 4389448 describes a flexible polyurethane foam substrate impregnated with an effective amount
of a conditioning agent and which has on at least one surface thereof a pattern which
is substantially totally removed from the substrate during the drying cycle thereby
indicating to the consumer or user of the article that the conditioning agent has
been substantially completely removed from the article during the course of the drying
cycle. The contents of these patents are incorporated by reference herein.
[0005] While these provide certain technical benefits, there is nonetheless a real and continuing
need in the art for further improved cleaning articles, especially flexible cleaning
articles as sponges which provide a residual antimicrobial affect, particularly which
is effective after a significant numbers of uses by a consumer. Accordingly, the present
invention addresses this need in the art as well as addresses other needs which will
become more apparent from reading the following specification.
[0006] Figure 1 depicts an embodiment of a molded cleaning article according to the invention.
[0007] Figure 2A and 2B depicts two views of a further embodiment of a cleaning article
according to the invention in the form of a multilayered cleaning article.
[0008] Figures 3A, 3B and 3C depict several views of a yet further embodiment of a cleaning
article according to the invention in the form of a tri-layered cleaning article.
[0009] In an aspect of the invention there is provided a foamed polyurethane composition
which exhibits an antimicrobial benefit, which may be used to form foamed polyurethane
articles, as well as cleaning articles.
[0010] In another aspect of the present invention there is provided a cleaning article comprising
a foamed polyurethane composition which exhibits an antimicrobial benefit, such as
a sponge, sheet, tape or ribbon, block or other molded, extruded or cast article which
cleaning articles exhibit an antimicrobial benefit.
[0011] In a further aspect of the invention there is provided a cleaning article comprising
a foamed polyurethane composition which exhibits an antimicrobial benefit, wherein
the cleaning article comprises at least one layer of a fibrous substrate bonded to
a sponge formed from the foamed polyurethane composition.
[0012] A further aspect of the invention relates to a process for the manufacture of cleaning
articles, such as sponges, sheets, tapes or ribbons, blocks or other molded, extruded
or cast articles which cleaning articles exhibit an antimicrobial benefit.
[0013] A yet further aspect of the invention is directed to a process for providing a residual
antimicrobial benefit to a cleaning article comprising a foamed polyurethane composition.
[0014] A still further aspect of the invention relates to a process for cleaning and/or
sanitizing a surface in need of treatment which process contemplates the steps of:
providing a cleaning article comprising a foamed polyurethane composition, e.g., sponges,
sheets, tapes, blocks or other molded, extruded or cast articles which foamed polyurethane
composition exhibit an antimicrobial benefit; and, contacting the said surface with
the said cleaning article so to provide a cleaning and/or sanitizing effect thereto.
[0015] In a yet further aspect of the invention there is provided a process for the cleaning
and/or disinfecting treatment of hard surfaces which contemplates the use of a cleaning
article as described herein, wherein said cleaning article is applied to the locus
of a stain or to an area wherein the presence of an undesirable microorganism, e.g.
a bacteria, or virus is suspected, and contacted said surface with the cleaning article
in order to eradicate the undesirable microorganism.
[0016] These and other aspects of the invention, especially preferred aspects will become
more apparent from the reading of the following specification.
[0017] The foamed polyurethane composition of the present invention is particularly adapted
to be used as a cleaning article or used in the construction of a cleaning article
which cleaning articles exhibit a residual antimicrobial benefit. In one aspect, the
present invention provides a foamed polyurethane composition which exhibits an antimicrobial
benefit, said foamed hydrophilic polyurethane composition comprising:
0.001-10% by weight of one or more quaternary ammonium compounds having germicidal
properties generally distributed throughout the composition,
a detersive surfactant constituent consisting of one or more nonionic, cationic, zwitterionic,
and amphoteric surfactants in an amount which does not exceed about 10%wt.,
wherein the non-ionic surfactant is selected from polyalkylene oxide condensates of
alkyl phenols, condensation products of aliphatic alcohols with 1 to about 60 moles
of an alkylene oxide, primary and secondary linear and branched alcohol ethoxylates,
alkoxy block copolymers, alkylmonoglucosides, alkylpolyglucosides and amine oxides,
wherein the foamed hydrophilic polyurethane composition exhibits a density of at least
0.25 g/cm3,
formed by a process which comprises the process steps of:
providing a reaction mixture comprising at least a polyurethane prepolymer, said quaternary
ammonium compound having germicidal properties, and said detersive surfactant constituent
consisting of one or more nonionic, cationic, zwitterionic, and amphoteric surfactants;
and, subsequently forming the foamed hydrophilic polyurethane composition, which,
following at least twenty five (25) rinse/squeeze cycles exhibits an elution of at
least about 100 parts per million, preferably at least about 150 parts per million
of germicidal quaternary ammonium compounds in the fluid squeezed or wrung from the
article.
[0018] Preferably said foamed polyurethane composition exhibits a density in the range of
from about 0.3-0.4g/cm
3, most desirably a density in the range of about 0.3 - 0.36 g/cm
3 The foamed polyurethane composition necessarily contains a sufficient amount of a
quaternary ammonium compounds having germicidal properties in order to impart an antimicrobial
benefit to the foamed polyurethane composition. Said foamed polyurethane composition
preferably contains from about 0.1 - 10%wt., more preferably about 0.3-10%wt, and
most preferably about 0.5 - 10%wt.of at least one quaternary ammonium compound having
germicidal properties generally uniformly distributed throughout. The foamed polyurethane
composition may be used solely as hydrophilic foams providing an antimicrobial benefit,
as well as in forming cleaning articles which may consist wholly of, or only partially
of the foamed polyurethane composition which exhibits an antimicrobial benefit.The
polyurethane foam compositions of the invention is hydrophilic, and is capable of
absorbing water, as well as containing and releasing a quaternary ammonium compound
having germicidal properties.
[0019] The foamed polyurethane composition are advantageously formed of a polyurethane prepolymer
composition which is used to form a foamed article, especially a foamed article having
hydrophilic properties. The selection of the polyurethane prepolymer is not critical
and it is expected that any of a variety of known and commercially available polyurethane
prepolymers may be used. The hydrophilic polyurethane foam compositions of the present
invention are prepared using an isocyanate-capped polyether prepolymer. Isocyanate-capped
polyether prepolymers such as those disclosed in
U.S. Pat. No. 4,137,200 are suitable for use in the present invention. These prepolymers have a defined average
isocyanate functionality greater than 2. These prepolymers may be capped with aromatic
isocyanates, such as, methylene diphenyl isocyanate (MDI), or mixtures of MDI with
toluene diisocyanate (TDI) and/or polymeric forms of MDI. Isocyanate-capped polyether
prepolymers which have been found suitable for use in the practice of the present
invention include prepolymers sold by Hampshire Chemical Company the HYPOL® trademark.
Examples include HYPOL FHP 3000, HYPOL FHP 2002, HYPOL FHP 3000, HYPOL FHP 4000. HYPOL
FHP 5000, HYPOL X6100, HYPOL JT 6000, and HYPOL hydrogel. The HYPOL FHP 4000 and HYPOL
FHP 5000 prepolymers are derived from methylene diisocyanate. These resins possess
molecular weights within the range of about 1300-1400 and have about 1.5-2.6 mEq/g
of free isocyanate groups. Upon being contacted with a molar excess of water, the
isocyanate groups hydrolyze to release carbon dioxide gas, thus foaming the resin
without the need for added catalysts or blowing agents. The free amino groups formed
by the hydrolysis reaction react with unhydrolyzed isocyanate groups to form urea
groups which crosslink, with additional ioscyanurate group to form urethane and stabilize
the foam, while entrapping a part of the excess water in the cell walls, where it
acts to impart hydrophilic properties to the foam.
[0020] In addition to the MDI or MDI with TDI, polymeric polyisocyanate may be incorporated
into the polyurethane prepolymer. The commercially available PAPI series made by Dow
Chemical Company is a family of polymeric MDI produced by the reaction of carbonyl
chloride with an aniline-formaldehyde condensate. The PAPI family consists of mixtures
of MDI and the polymeric forms of the phenyl isocyanates that make up MDI which are
linked together by methylene groups. Another example of an isocyanatc-capped prepolymer
preferably used in the present invention is ISO 247, a product of BASF Corporation.
This prepolymer is formed from about two thirds polyether polyol and one third isocyanate.
The polyol has about 75 percent by weight ethylene oxide and about 25%wt, propylene
oxide with a trifunctional initiator. The isocyanate comprises a combination of methylene
diphenyl diisocyanate (MDI) and other polymeric MDI. ISO 247 prepolymers have an NCO
weight percent of 10.15.
[0021] The amount of polyurethane prepolymer in the reaction mixture used to prepare the
hydrophilic polyurethane foam composition is not particularly critical, but depends
on a number of factors, including the proportion of other components in the reactant
composition as described in greater detail below. There should, however, be sufficient
polyurethane prepolymer to form a polyurethane foam. The polyurethane prepolymers
may be used singly or in combination.
[0022] The polyurethane prepolymer is foamed in the presence of an aqueous component, preferably
water, in the conventional manner known in the art. The aqueous component may also
be a water slurry or suspension, a water emulsion, or a water solution having water
soluble materials disposed therein.The reaction mixture which contains at least the
polyurethane prepolymer, and a quaternary ammonium compound having germicidal properties.
The reaction mixture typically contains further constituents which take part in reaction
whereby the polyurethane foams which exhibit an antimicrobial benefit are formed.
During the reaction wherein the polyurethane foam is formed, the amount of water present
in the reaction mixture reacts with the free isocyanate groups to release carbon dioxide,
which blows the polyurethane prepolymer into a cross-linked, open-celled foam which
is rendered hydrophilic by the integral entrapment of excess water in the cell walls
of the foam matrix. When the reaction mixture is allowed to set in molds, a flexible,
resilient foam body of the desired shape is formed. Alternately the reaction mixture
may be applied to a substrate such as sheet, plate, film but especially a silicone
coated release sheet and allowed to set, which may provide a flexible resilient foam
body in a generally planar or sheet form. The reaction mixture, and the foamed polyurethane
compositions ultimately formed therefrom also necessarily include as one or morequaternary
ammonium compounds having germicidal properties. Desirably the one or morequaternary
ammonium compounds having germicidal properties are provided to provide a long term
antimicrobial benefit to the foamed polyurethane composition and particularly to cleaning
articles formed therefrom or therewith. Per se, many quaternary ammonium compounds
are known and are contemplated as being useful in the present inventive compositions.
Such quaternary ammonium compound having germicidal properties are well known, and
many of these are categorized as cationic surfactants including those described for
example in
McCutcheon's Functional Materials, Vol.2, 1998;
Kirk-Othmer, Encyclopedia of Chemical Technology, 4th Ed., Vol. 23, pp. 481-541 (1997), the contents of which are herein incorporated by reference. Useful quaternary ammonium
compounds having germicidal properties are also described in the respective product
specifications and literature available from the suppliers of these cationic surfactants.
[0023] Examples of preferred cationic surfactant compositions useful in the practice of
the instant invention are those which provide a germicidal effect to the foamed polyurethane
composition, and especially preferred are quaternary ammonium compounds and salts
thereof, which may be characterized by the general structural formula:

where at least one of R
1, R
2, R
3 and R
4 is a alkyl, aryl or alkylaryl substituent of from 6 to 26 carbon atoms, and the entire
cation portion of the molecule has a molecular weight of at least 165. The alkyl substituents
may be long-chain alkyl, long-chain alkoxyaryl, long-chain alkylaryl, halogen-substituted
long-chain alkylaryl, long-chain alkylphenoxyalkyl, arylalkyl, etc. The remaining
substituents on the nitrogen atoms other than the abovementioned alkyl substituents
are hydrocarbons usually containing no more than 12 carbon atoms. The substituents
R
1, R
2, R
3 and R
4 may be straight-chained or may be branched, but are preferably straight-chained,
and may include one or more amide, ether or ester linkages. The counterion X may be
any salt-forming anion which permits water solubility of the quaternary ammonium complex.
[0024] Exemplary quaternary ammonium salts within the above description include the alkyl
ammonium halides such as cetyl trimethyl ammonium bromide, alkyl aryl ammonium halides
such as octadecyl dimethyl benzyl ammonium bromide, N-alkyl pyridinium halides such
as N-cetyl pyridinium bromide, and the like. Other suitable types of quaternary ammonium
salts include those in which the molecule contains either amide, ether or ester linkages
such as octyl phenoxy ethoxy ethyl dimethyl benzyl ammonium chloride, N-(laurylcocoaminoformylmethyl)-pyridinium
chloride, and the like. Other very effective types of quaternary ammonium compounds
which are useful as germicides include those in which the hydrophobic radical is characterized
by a substituted aromatic nucleus as in the case of lauryloxyphenyltrimethyl ammonium
chloride, cetylaminophenyltrimethyl ammonium methosulfate, dodecylphenyltrimethyl
ammonium methosulfate, dodecylbenzyltrimethyl ammonium chloride, chlorinated dodecylbenzyltrimethyl
ammonium chloride, and the like.
[0025] Preferred quaternary ammonium compounds which act as germicides and which are found
useful in the foamed polyurethane composition include those which have the structural
formula:

wherein R
2 and R
3 are the same or different C
8-C
12alkyl, or R
2 is C
12-16alkyl, C
8-
18alkylethoxy, C
8-18alkylphenolethoxy and R
3 is benzyl, and X is a halide, for example chloride, bromide or iodide, or is a methosulfate
anion. The alkyl groups recited in R
2 and R
3 may be straight-chained or branched, but are preferably substantially linear.
[0026] Particularly useful quaternary germicides include compositions which include a single
quaternary compound, as well as mixtures of two or more different quaternary compounds.
Such useful quaternary compounds are available under the BARDAC®, BARQUAT®, HYAMINE®,
LONZABAC®, and ONYXIDE® trademarks, which are more fully described in, for example,
McCutcheon's Functional Materials (Vol. 2), North American Edition, 1998, as well as the respective product literature from the suppliers identified below.
For example, BARDAC® 205M is described to be a liquid containing alkyl dimethyl benzyl
ammonium chloride, octyl decyl dimethyl ammonium chloride; didecyl dimethyl ammonium
chloride, and dioctyl dimethyl ammonium chloride (50% active) (also available as 80%
active (BARDAC® 208M)); described generally in
McCutcheon's as a combination of alkyl dimethyl benzyl ammonium chloride and dialkyl dimethyl
ammonium chloride); BARDAC® 2050 is described to be a combination of octyl decyl dimethyl
ammonium chloride/didecyl dimethyl ammonium chloride, and dioctyl dimethyl ammonium
chloride (50% active) (also available as 80% active (BARDAC® 2080)); BARDAC ® 2250
is described to be didecyl dimethyl ammonium chloride (50% active); BARDAC® LF (or
BARDAC® LF-80), described as being based on dioctyl dimethyl ammonium chloride (BARQUAT®
MB-50, MX-50, OJ-50 (each 50% liquid) and MB-80 or MX-80 (each 80% liquid) are each
described as an alkyl dimethyl benzyl ammonium chloride; BARDAC® 4250 and BARQUAT®
4250Z (each 50% active) or BARQUAT® 4280 and BARQUAT 4280Z (each 80% active) are each
described as alkyl dimethyl benzyl ammonium chloride/alkyl dimethyl ethyl benzyl ammonium
chloride. Also, HYAMINE® 1622, described as diisobutyl phenoxy ethoxy ethyl dimethyl
benzyl ammonium chloride (50% solution); HYAMINE® 3500 (50% actives), described as
alkyl dimethyl benzyl ammonium chloride (also available as 80% active (HYAMINE® 3500-80));
and HYAMINE® 2389 described as being based on methyldodecylbenzyl ammonium chloride
and/or methyldodecylxylene-bis-trimethyl ammonium chloride. (BARDAC®, BARQUAT® and
HYAMINE® are presently commercially available from Lonza, Inc., Fairlawn, New Jersey).
BTC® 50 NF (or BTCC® 65 NF) is described to be alkyl dimethyl benzyl ammonium chloride
(50% active); BTC® 99 is described as didecyl dimethyl ammonium chloride (50% acive);
BTC® 776 is described to be myrisalkonium chloride (50% active); BTC® 818 is described
as being octyl decyl dimethyl ammonium chloride, didecyl dimethyl ammonium chloride,
and dioctyl dimethyl ammonium chloride (50% active) (available also as 80% active
(BTC® 818-80%)); BTC® 824 and BTC® 835 are each described as being of alkyl dimethyl
benzyl ammonium chloride (each 50% active); BTC® 885 is described as a combination
of BTC® 835 and BTC® 818 (50% active) (available also as 80% active (BTC® 888)); BTC®
1010 is described as didecyl dimethyl ammonium chloride (50% active) (also available
as 80% active (BTC® 1010-80)); BTC® 2125 (or BTC® 2125 M) is described as alkyl dimethyl
benzyl ammonium chloride and alkyl dimethyl ethylbenzyl ammonium chloride (each 50%
active) (also available as 80% active (BTC® 2125 80 or BTC® 2125 M)); BTC® 2565 is
described as alkyl dimethyl benzyl ammonium chlorides (50% active) (also available
as 80% active (BTC® 2568)); BTC® 8248 (or BTC® 8358) is described as alkyl dimethyl
benzyl ammonium chloride (80% active) (also available as 90% active (BTC® 8249));
ONYXIDE® 3300 is described as n-alkyl dimethyl benzyl ammonium saccharinate (95% active).
(BTC® and ONYXIDE® are presently commercially available from Stepan Company, Northfield,
Illinois.) Polymeric quaternary ammonium salts based on these monomeric structures
arc also considered desirable for the present invention. One example is POLYQUAT®,
described as being a 2-butenyldimethyl ammonium chloride polymer.
[0027] The inventors have observed that not all quaternary ammonium compounds having germicidal
properties necessarily provide for the optimal foaming of the polyurethane prepolymer
and resultant foamed polyurethane composition which exhibits good resilience, good
flexibility and good product integrity, and for these reasons certain quaternary ammonium
compounds are presently preferred over others. For example, such preferred quaternary
ammonium compounds include those selected from the following: BTC® 65, BTC® 2125M90,
BTC® 8358, CATIGENE® T50, and HYAMINE®1622. BTC® 65 is a commercially available preparation
which is described to contain in 50%wt, of a C
12-C
16 alkyl dimethyl benzyl ammonium chlorideprovided in an aqueous alcoholic carrier wherein
water comprises 46%wt, of the commercial preparation, and ethanol comprises the remaining
4%wt, of the commercial preparation. BTC® 2125M90 is a commercial available preparation
which is described to contain 45%wt, of a C
12-C
16 dimethyl benzyl ammonium chloride, 45%wt. of a C
12-C
18 alkyldimethyl(ethylbenzyl) ammonium chloride, 4%wt. water, 3%wt. ethanol, and the
remaining balance of 3%wt. comprising C
12-C
18 alkylmethylamines. BTC® 8358 is a commercially available preparation which is described
to contain 80%wt, of a C
12-C
16 alkyl dimethyl benzyl ammonium chloride, 17%wt. of ethanol, 2%wt. water, and 1%wt,
of C
12-C
16 alkyldimethyl amines. CATIGENE® T50 is a commercially available preparation containing
50%wt. of a C
8-C
18 alkyl dimethyl benzalkonium ammonium chloride and 50%wt, water, HYAMINE® 1622 Crystal
is a commercially available anhydrous preparation which is described to contain 100%wt.
of diisobuylphenoxyethoxyethyl dimethyl benzyl ammonium chloride. As is evident from
the above, the concentration of the active quaternary ammonium compounds in each one
of these commercial compositions varies, and the composition of the aqueous/alcoholic
solution varies as well.
[0028] While not wishing to be bound by the following, one of more of the following factors
may contribute to the advantages of the preferred quaternary ammonium compounds over
others. One possible factor is that the preferred quaternary ammonium compounds are
provided in commercial preparations which may contain non-quatemized alkyldimethylamines
in appreciable amounts. Another possible factor is that the preferred quaternary ammonium
compounds provided in commercial preparations contain at least one benzyl moiety within
the structure of the quaternary ammonium compounds providing the germicidal properties.
[0029] According to certain particularly preferred embodiments, the preferred quaternary
ammonium compounds are the sole constituents which provide a germicidal effect to
the formed articles.
[0030] Most preferably the inventive articles and compositions for their production exclude
sources of silver ions such as disclosed in
US 6375964 the contents of which are herein incorporated by reference.
[0031] It will be appreciated that further constituents may optionally be added to the reaction
mixture in order to ultimately impart desired properties to the foamed polyurethane
composition and/or to cleaning articles comprising the foamed polyurethane composition.
If desired, the reaction mixture may contain fillers, stabilizers, additives such
as reinforcing agents, auxiliary blowing agents, fragrances, deodorizers, colorants,
one or more detersive surfactants, silicone oils, rubbers, abrasive powders and the
like. Preferably, all such fillers, stabilizers, additives and the like will be substantially
nonreactive with the isocyanate and hydroxy groups under the conditions of foam formulation.
[0032] The detersive surfactant constituent consists of one or more nonionic, cationic,
zwitterionic, and amphoteric surfactants in an amount which does not exceed about
10%wt.,
wherein the non-ionic surfactant is selected from polyalkylene oxide condensates of
alkyl phenols, condensation products of aliphatic alcohols with 1 to about 60 moles
of an alkylene oxide, primary and secondary linear and branched alcohol ethoxylates,
alkoxy block copolymers, alkylmonoglucosides, alkylpolyglucosides and amine oxides.
[0033] Suitable nonionic surfactants which are used in the present invention include the
following:
Polyalkylene oxide condensates of alkyl phenols. These compounds include the condensation
products of alkyl phenols having an alkyl group containing from about 6 to 12 carbon
atoms in either a straight chain or branched chain configuration with an
alkylene oxide, especially an ethylene oxide, the ethylene oxide being present in
an amount equal to 5 to 25 moles of ethylene oxide per mole of alkyl phenol. The alkyl
substituent in such compounds can be derived, for example, from polymerized propylene,
diisobutylene and the like. Examples of compounds of this type include nonyl phenol
condensed with about 9.5 moles of ethylene oxide per mole of nonyl phenol; dodecylphenol
condensed with about 12 moles of ethylene oxide per mole of phenol; dinonyl phenol
condensed with about 15 moles of ethylene oxide per mole of phenol and diisooctyl
phenol condensed with about 15 moles of ethylene oxide per mole of phenol.
[0034] A further class of nonionic surfactants are the condensation products of aliphatic
alcohols with from about 1 to about 60 moles of an alkylene oxide, especially an ethylene
oxide. The alkyl chain of the aliphatic alcohol can either be straight or branched,
primary or secondary, and generally contains from about 8 to about 22 carbon atoms.
Examples of such ethoxylated alcohols include the condensation product of myristyl
alcohol condensed with about 10 moles of ethylene oxide per mole of alcohol and the
condensation product of about 9 moles of ethylene oxide with coconut alcohol (a mixture
of fatty alcohols with alkyl chains varying in length from about 10 to 14 carbon atoms).
Other examples are those C
6-C
11 straight-chain alcohols which are ethoxylated with from about 3 to about 6 moles
of ethylene oxide. Their derivation is well known in the art. Examples include Alfonic®
810-4.5, which is described in product literature from Sasol as a C8-10 having an
average molecular weight of 356, an ethylene oxide content of about 4.85 moles (about
60 wt.%), and an HLB of about 12; Alfonic® 810-2, which is described in product literature
as a C8-C10 having an average molecular weight of 242, an ethylene oxide content of
about 2.1 moles (about 40 wt.%), and an HLB of about 12; and Alfonic® 610-3.5, which
is described in product literature as having an average molecular weight of 276, an
ethylene oxide content of about 3.1 moles (about 50 wt.%), and an HLB of 10. Other
examples of alcohol ethoxylates are C10 oxo-alcohol ethoxylates available from BASF
under the Lutensol® ON tradename. They are available in grades containing from about
3 to about 11 moles of ethylene oxide (available under the names Lutensol® ON 30;
Lutensol® ON 50; Lutensol® ON 60; Lutensol® ON 65; Lutensol® ON 66; Lutensol® ON 70;
Lutensol® ON 80; and Lutensol®ON 110). Other examples of ethoxylated alcohols include
the Neodol® 91 series non-ionic surfactants available from Shell Chemical Company
which are described as C
9-C
11 ethoxylated alcohols. The Neodol® 91 series non-ionic surfactants of interest include
Neodol® 91-2.5, Neodol® 91-6, and Neodol® 91-8. Neodol® 91-2.5 has been described
as having about 2.5 ethoxy groups per molecule; Neodol 91-6 has been described as
having about 6 ethoxy groups per molecule; and Neodol 91-8 has been described as having
about 8 ethoxy groups per molecule.Further examples of ethoxylated alcohols include
the Rhodasurf® DA series non-ionic surfactants available from Rhodia which are described
to be branched isodecyl alcohol ethoxylates. Rhodasurf® DA-530 has been described
as having 4 moles of ethoxylation and an HLB of 10.5; Rhodasurf® DA-630 has been described
as having 6 moles of ethoxylation with an HLB of 12.5; and Rhodasurf® DA-639 is a
90% solution of DA-630. Further examples of ethoxylated alcohols include those from
Tomah Products (Milton, WI) under the Tomadol® tradename with the formula RO(CH
2CH
2O)
nH where R is the primary linear alcohol and n is the total number of moles of ethylene
oxide. The ethoxylated alcohol series from Tomah include 91-2.5; 91-6; 91-8 - where
R is linear C
9/C
10/C
11 and n is 2.5, 6, or 8; 1-3; 1-5; 1-7; 1-73B; 1-9; where R is linear C
11 and n is 3, 5, 7 or 9; 23-1; 23-3; 23-5; 23-6.5 - where R is linear C
12/C
13 and n is 1, 3, 5, or 6.5; 25-3; 25-7; 25-9; 25-12 - where R is linear C
12/C
13/C
14/C
15 and n is 3, 7, 9, or 12; and 45-7; 45-13 - where R is linear C
14/ C
15 and n is 7 or 13.
A further class of nonionic surfactants are primary and secondary linear and branched
alcohol ethoxylates, such as those based on C
6-C
18 alcohols which further include an average of from 2 to 80 moles of ethoxylation per
mol of alcohol. These examples include the Genapol® UD (ex. Clariant, Muttenz, Switzerland)
described under the tradenames Genapol® UD 030, C
11-oxo-alcohol polyglycol ether with 3 EO; Genapol® UD, 050 C
11-oxo-alcohol polyglycol ether with 5 EO; Genapol® UD 070, C
11-oxo-alcohol polyglycol ether with 7 EO; Genapol® UD 080, C
11-oxo-alcohol polyglycol ether with 8 EO; Gcnapol® UD 088, C
11-oxo-alcohol polyglycol ether with 8 EO; and Genapol® UD 110, C
11-oxo-alcohol polyglycol ether with 11 EO.
[0035] A further class of useful nonionic surfactants includethose surfactants having a
formula RO(CH
2CH
2O)
nH of linear, even carbon-number hydrocarbon chains ranging from C
12H
25 to C
16H
33 and n represents the number of repeating units and is a number of from about 1 to
about 12. Surfactants of this formula are presently marketed under the Genapol® tradename(ex.
Clariant), which surfactants include the "26-L" series of the general formula RO(CH
2CH
2O)
nH wherein R is a mixture of linear, even carbon-number hydrocarbon chains ranging
from C
12H
25 to C
16H
33 and n represents the number of repeating units and is a number of from 1 to about
12, such as 26-L-1, 26-L-1 6, 26-L-2, 26-L-3, 26 L-5, 26-L-45, 26-L-50, 26-L-60, 26-L-60N,
26-L-75, 26-L-80, 26-L-98N, and the 24-L series, derived from synthetic sources and
typically contain about 55% C
12 and 43% C
14 alcohols, such as 24 L-3, 24-L-45, 24-L-50, 24-L-60, 24-L-60N, 24-L-75, 24-L-92,
and 24-L-98N, all sold under the Genapol® tradename.
[0036] A further class of useful nonionic surfactants include alkoxy block copolymers, and
in particular, compounds based on ethoxy/propoxy block copolymers. Polymeric alkylene
oxide block copolymers include nonionic surfactants in which the major portion of
the molecule is made up of block polymeric C
2-C
4 alkylene oxides. Such nonionic surfactants, while preferably built up from an alkylene
oxide chain starting group, and can have as a starting nucleus almost any active hydrogen
containing group including, without limitation, amides, phenols, thiols and secondary
alcohols.
[0037] One group of such useful nonionic surfactants containing the characteristic alkylene
oxide blocks are those which may be generally represented by the formula (A):
R-(EO)
x(PO)
y(EO)
z-H (A)
where R represents a hydroxyl group or an alkyl group,
EO represents ethylene oxide,
PO represents propylene oxide,
y equals at least 15,
(EO)
x+z equals 20 to 80% of the total weight of said compounds, and, the total molecular
weight is preferably in the range of about 2000 to 15,000. These surfactants are available
under the PLURONIC®(ex. BASF) wherein R is -OH, or when R is an alkyl group, EMULGEN®
(ex. Kao.)
[0038] A further group of such useful nonionic surfactants containing the characteristic
alkylene oxide blocks are those can be represented by the formula (B):
R-(EO,PO)
a(EO,PO)
b-H (B)
wherein R is an alkyl, aryl or aralkyl group, where the R group contains 1 to 20 carbon
atoms, the weight percent of EO is within the range of 0 to 45% in one of the blocks
a, b, and within the range of 60 to 100% in the other of the blocks a, b, and the
total number of moles of combined EO and PO is in the range of 6 to 125 moles, with
1 to 50 moles in the PO rich block and 5 to 100 moles in the EO rich block. Specific
nonionic surfactants which in general are encompassed by Formula B include butoxy
derivatives of propylene oxide/ethylene oxide block polymers having molecular weights
within the range of about 2000-5000.
[0039] Still further examples of useful nonionic surfactants include those which can be
represented by formula (C) as follows:
RO-(BO)
n(EO)
x-H (C)
wherein ED represents ethylene oxide,
BO represents butylene oxide,
R is an alkyl group containing 1 to 20 carbon atoms,
n is about 5-15 and x is about 5-15.
Yet further useful nonionic surfactants include those which may be represented by
the following formula (D):
HO-(EO)
x(BO)
n(EO)
y-H (D)
wherein EO represents ethylene oxide,
BO represents butylene oxide,
n is about 5-15, preferably about 15,
x is about 5-15, preferably about 15, and
y is about 5-15, preferably about 15.
[0040] Still further exemplary useful nonionic block copolymer surfactants include ethoxylated
derivatives of propoxylatcd ethylene diamine, which may be represented by the following
formula:

where (EO) represents ethoxy,
(PO) represents propoxy, the amount of (PO)
x is such as to provide a molecular weight prior to ethoxylation of about 300 to 7500,
and the amount of (EO)
y is such as to provide about 20% to 90% of the total weight of said compound.
[0041] Particularly preferred for use as nonionic surfaetants include those presently marketed
under the trade name Pluronic® (ex. BASF). The compounds are formed by condensing
ethylene oxide with a hydrophobic base formed by the condensation of propylene oxide
with propylene glycol, and are described by their manufacturer to have the following
general structure:

wherein x, y and z are selected such that the molecular weight of the block polymers
varies from at least about 7,000 to about 15,000 preferably about 11,000 to about
15,000 and the polyethylene oxide content may comprise 5% to 90% by weight of the
block polymer. Preferably, these surfactants are in liquid form and particularly satisfactory
surfactants are available as those marketed as Pluronic® F88 described to have a molecular
weight of about 11400, Pluronic® F98 described to have a molecular weight of about
13000, Pluronic® F108 described to have a molecular weight of about 14600, and Pluronic®
F127 described to have a molecular weight of about 12600.
[0042] In certain preferred embodiments there is at least one nonionic surfactant present
which nonionic surfactant is based on ethoxy/propoxy units; according to certain especially
preferred embodiments the sole nonionic surfactant present is a nonionic block copolymer
as described above within the Pluronic® series of surfactants, especially the nonionic
surfactant described as Pluronic® F88.
[0043] Alkylmonoglycosides and alkylpolyglycosides which may also find use in the present
inventive compositions include known noninic surfactants which are alkaline and electrolyte
stable. Alkylmonoglycosides and alkylpolyglycosides are prepared generally by reacting
a monosaccharide, or a compound hydrolyzable to a monosaccharide with an alcohol such
as a fatty alcohol in an acid medium. Various glycoside and polyglycoside compounds
including alkoxylated glycosides and processes for making them are disclosed in
U.S. Pat. Nos. 2,974,134;
3,219,656;
3,598,865;
3,640,998;
3,707,535,
3,772,269;
3,839,318;
3,974,138;
4,223,129 and
4,528,106 the contents of which are incorporated by reference.
One exemplary group of such useful alkylpolyglycosides include those according to
the formula:
R
2O-(C
nH
2nO)
r-(Z)
x
wherein:
R2 is a hydrophobic group selected from alkyl groups, alkylphenyl groups, hydroxyalkylphenyl
groups as well as mixtures thereof, wherein the alkyl groups may be straight chained
or branched, and which contain from about 8 to about 18 carbon atoms,
n has a value of 2 - 8, especially a value of 2 or 3;
r is an integer from 0 to 10, but is preferably 0,
Z is derived from glucose; and,
x is a value from about 1 to 8, preferably from about 1.5 to 5.
[0044] Preferably the alkylpolyglycosides are nonionic fatty alkylpolyglucosides which contain
a straight chain or branched chain C
8 -C
15 alkyl group, and have an average of from about 1 to 5 glucose units per fatty alkylpolyglucoside
molecule. More preferably, the nonionic fatty alkylpolyglucosides which contain straight
chain or branched C
8 -C
15 alkyl group, and have an average of from about 1 to about 2 glucose units per fatty
alkylpolyglucoside molecule.
[0045] A further exemplary group of alkyl glycoside surfactants suitable for use in the
practice of this invention may be presented by the following formula (A):
RO-(R
1O)
y-(G)
xZ
b (A)
wherein:
R is a monovalent organic radical containing from about 6 to about 30, preferably
from about 8 to 18 carbon atoms,
R1 is a divalent hydrocarbon radical containing from about 2 to about 4 carbon atoms,
y is a number which has an average value from about 0 to about 1 and is preferably
0,
G is a moiety derived from a reducing saccharide containing 5 or 6 carbon atoms; and,
x is a number having an average value from about 1 to 5 (preferably from 1.1 to 2);
Z is O2M1,

O(CH2), CO2M1, OSO3M1, or O(CH2)SO3M1; R2 is (CH2)CO2 M1 or CH=CHCO2M1 ; (with the proviso that Z can be O2M1 only if Z is in place of a primary hydroxyl group in which the primary hydroxyl-bearing
carbon atom,-CH2OH, is oxidized to form a

group)
b is a number of from 0 to 3x+1 preferably an average of from 0.5 to 2 per glycosal
group; p is 1 to 10, M1 is H+ or an organic or inorganic counterion, particularly cations such as, for example,
an alkali metal cation, ammonium cation, monoethanolamine cation or calcium cation.
As defined in Formula (A) above, R is generally the residue of a fatty alcohol having
from about 8 to 30 and preferably 8 to 18 carbon atoms.
[0046] Examples of such alkylglycosides as described above include, for example APG 325
CS Glycoside® which is described as being a 50% C
9 -C
11 alkyl polyglycoside, also commonly referred to as D-glucopyranoside, (commercially
available from Henkel KGaA) and Glueopon® 625 CS which is described as being a 50%
C
10 -C
16 alkyl polyglycoside, also commonly referred to as a D-glueopyranoside, (ex. Henkel).
[0047] The inventive compositions may also include a nonionic amine oxide constituent. Exemplary
amine oxides include:
- (A) Alkyl di (lower alkyl) amine oxides in which the alkyl group has about 10-20,
and preferably 12-16 carbon atoms, and can be straight or branched chain, saturated
or unsaturated. The lower alkyl groups include between 1 and 7 carbon atoms. Examples
include lauryl dimethyl amine oxide, myristyl dimethyl amine oxide, and those in which
the alkyl group is a mixture of different amine oxide, dimethyl cocoamine oxide, dimethyl
(hydrogenated tallow) amine oxide, and myristyl/palmityl dimethyl amine oxide;
- (B) Alkyl di (hydroxy lower alkyl) amine oxides in which the alkyl group has about
10-20, and preferably 12-16 carbon atoms, and can be straight or branched chain, saturated
or unsaturated. Examples, arc bis(2-hydroxyethyl) cocoamine oxide, bis(2-hydroxyethyl)
tallowaminc oxide; and bis(2-hydroxyethyl) stearylamine oxide;
- (C) Alkylamidopropyl di(lower alkyl) amine oxides in which the alkyl group has about
10-20, and preferably 12-16 carbon atoms, and can be straight or branched chain, saturated
or unsaturated. Examples are cocoamidopropyl dimethyl amine oxide and tallowamidopropyl
dimethyl amine oxide; and
- (D) Alkylmorpholine oxides in which the alkyl group has about 10-20, and preferably
12-16 carbon atoms, and can be straight or branched chain, saturated or unsaturated.
[0048] Preferably the amine oxide constituent is an alkyl di (lower alkyl) amine oxide as
denoted above and which may be represented by the following structure:

wherein each:
R1 is a straight chained C1-C4 alkyl group, preferably both R1 are methyl groups; and,
R2 is a straight chained C8-C18 alkyl group, preferably is C10-C14alkyl group, most preferably is a C12 alkyl group.Each of the alkyl groups may be linear or branched, but most preferably
are linear. Most preferably the amine oxide constituent is lauryl dimethyl amine oxide.
Technical grade mixtures of two or more amine oxides may be used, wherein amine oxides
of varying chains of the R2 group are present. Preferably, the amine oxides, used in the present invention include
R2 groups which comprise at least 50%nwt., preferably at least 60%wt. of C12 alkyl groups and at least 25%wt. of C14 alkyl groups, with not more than 15%wt. of C16, C18 or higher alkyl groups as the R2 group.
[0049] Of course the nonionic surfactant constituent, when present, may comprise two or
more nonionic surfactants. When present, the nonionic surfactant is present in the
compositions of the present invention in an amount of from about 0.1 % to about 10%
by weight, more preferably is present in an amount of from about 1 -5%wt., and most
preferably in an amount of from about 1-3.5%wt.
[0050] The compositions according to the present invention may include one or more further
detersive surfactants particularly those selected from amongst amphoteric and zwitterionic
surfactants, particularly those which may provide a detersive effect to the compositions.
By way of non-limiting example, zwitterionic surfactants and amphoteric surfactants
may include one or more of the following.
[0051] For example the compositions according to the invention may optionally further comprise
an alkyl ethoxylated carboxylate surfactant. In particular, the alkyl ethoxylated
carboxylate comprises compounds and mixtures of compounds which may be represented
by the formula:
R
1(OC
2H
4)
n-OCH
2COO
-M
+
wherein R
1is a C
4-C
18 alkyl, n is from about 3 to about 20, and M is hydrogen, a solubilizing metal, preferably
an alkali metal such as sodium or potassium, or ammonium or lower alkanolammonium,
such as triethanolammonium, monoethanolammonium, or diisopropanolammonium. The lower
alkanol of such alkanotammonium will normally be of 2 to 4 carbon atoms and is preferably
ethanol. Preferably, R
1 is a C
12 - C
15 alkyl, n is from about 7 to about 13, and M is an alkali metal counterion.
[0052] Examples of alkyl ethoxylated carboxylates contemplated to be useful in the present
invention include, but are not necessarily limited to, sodium buteth-3 carboxylate,
sodium hexeth-4 carboxylate, sodium laureth-5 carboxylate, sodium laureth-6 carboxylate,
sodium laureth-8 carboxylate, sodium laureth-11 carboxylate, sodium laureth-13 carboxylate,
sodium trideceth-3 carboxylate, sodium trideceth-6 carboxylate, sodium trideceth-7
carboxylate, sodium trideceth-19 carboxylate, sodium capryleth-4 carboxylate, sodium
capryleth-6 carboxylate, sodium capryleth-9 carboxylate, sodium capryleth-13 carboxylate,
sodium ceteth-13 carboxylate, sodium C
12-
15 pareth- 6 carboxylate, sodium C
12-
15 pareth-7 carboxylate, sodium C
14-
15 pareth-8 carboxylate, isosteareth-6 carboxylate as well as the acid form. Sodiumlaureth-8
carboxylale, sodium laureth-13 carboxylate, pareth-25-7 carboxylic acid are preferred.
A particularly preferred sodium laureth-13 carboxylate can be obtained from Finetex
Inc. under the trade name Surfine® WILL or from Clariant Corp. under the trade name
Sandopan® LS-24.
[0053] By way of non-limiting example exemplary amphoteric surfactants include one or more
water-soluble betaine surfactants which may be represented by the general formula:

wherein: R
1 is an alkyl group containing from 8 to 18 carbon atoms, or the amido radical which
may be represented by the following general formula:

wherein R is an alkyl group having from 8 to 18 carbon atoms,
a is an integer having a value of from 1 to 4 inclusive, and
R
2 is a C
1-C
4 alkylene group. Examples of such water-soluble betaine surfactants include dodecyl
dimethyl betaine, as well as cocoamidopropylbetaine.
[0054] When present, any amphotericand/or zwitterionic surfactants present in the compositions
of the present invention are desirably included in an amount of from about 0.1 to
about 10% by weight.
[0055] The total amount of detersive surfactants present in the inventive compositions does
not exceed about 10%wt., more preferably does not execed about 5%wt. of the total
weight of the inventive composition. The detersive surfactants may be used singly,
or in mixtures of two or more surfactants.
[0056] A further constituent which is optionally, but in certain cases desirably included
in the foamed polyurethane compositions of the invention are one or more organic solvents
which provides both a solvency function, as well as an anti-foaming function. By way
of non limited example, such solvents can be virtually any organic solvent material.
By way of non-limiting example exemplary useful organic solvents which may be included
in the inventive compositions include those which are at least partially water-miscible
such as alcohols (e.g., low molecular weight alcohols, such as, for example, ethanol,
propanol, isopropanol, and the like), glycols (such as, for example, ethylene glycol,
propylene glycol, hexylene glycol, and the like), water-miscible ethers (e.g. diethylene
glycol diethylether, diethylene glycol dimethylether, propylene glycol dimethylether),
water-miscible glycol ether (e.g. propylene glycol monomethylether, propylene glycol
mono ethylether, propylene glycol monopropylether, propylene glycol monobutylether,
ethylene glycol monobutylether, dipropylene glycol monomethylether, diethyleneglycol
monobutylether), lower esters of monoalkylethers of ethylene glycol or propylene glycol
(e.g. propylene glycol monomethyl ether acetate), and mixtures thereof. Glycol ethers
having the general structure R
a-R
b-OH, wherein R
a is an alkoxy of 1 to 20 carbon atoms, or aryloxy of at least 6 carbon atoms, and
R
b is an ether condensate of propylene glycol and/or ethylene glycol having from one
to ten glycol monomer units. Of course, mixtures of two or more organic solvents may
be used in the organic solvent constituent. Desirably, when present the organic solvent
is selected to aid in the miscibility of one or more of the further constituents used
to make the foamed polyurethane composition, and at the same time impart at least
a minimal anti-foaming effect. This latter effect is often desired as during the in-situ
formation of the foamed polyurethane compositiona limited or controlled degree of
foaming is achieved. Excess or turbulent foaming is usually to be avoided as it typically
degrades the ultimate structural integrity of foamed polyurethane composition as well
as cleaning articles formed therefrom. Uncontrolled foaming may result in the uneven,
or poor distribution of gas bubbles within the foamed polyurethane compositionwhich
in turn, deleteriously affects the structural integrity of the foamed polyurethane
composition as well as any cleaning article formed thereform. Preferred organic solvents
are glycol ethers, of which a particularly preferred glycol ether solvent is dipropylene
glycol n-butyl ether which is commercially available, i.e. as Dowanol DPnB (Ex. Dow
Chemical).
[0057] As a further organic solvent, the reaction mixture may include a minor amount of
a low boiling point alcohol such as one C
1-C
4 monohydric alcohols, such as methanol, ethanol or propanol. Of these, the use of
methanol is particularly preferred. C
1-C
4 monohydric alcohol reduce the rate of reaction between the isocyanate-capped prepolymer
and water present in the reaction mixture. A reduction of the reaction rate, viz.,
in the polymerization and formation of the polyurethane foam is frequently desirable
in order to facilitate mixing of the various constituents used to produce the polyurethane
foams, and to permit for subsequent handling of the reaction mixture such as into
a mold, cavity or spreading it into a layer of suitable thickness for curing. Monohydric
alcohols serves to end cap some of the NCO end groups, preventing reaction with water
to form the urea linkage. Such also provides a more flexible polyuretheane foam composition.
Generally good results are observed when about one part by weight of the isocyanate-capped
prepolymer is mixed with water in the presence of from 0.05 to 0.25 parts by weight
of methanol or from 0.1 to 0.3 parts by weight of ethanol. When present any organic
solvents present in the compositions of the present invention are desirably included
in an amount of from about 0.01 to about 10% by weight.
[0058] One optional constituent which may also be included in the reaction mixture used
to form the foamed polyurethane composition is a rubber, which may be either natural
or synthetic. This has the effect of increasing the cure time for the polyurethane,
and increases extensibility, strength and tack. Preferably, the rubber is added in
the form of a latex, ie. a suspension or emulsion of the rubber in an aqueous medium.
The latex will generally comprise 40 to 70% solids by weight, preferably 50 to 60%
by weight. Acrylic-based rubbers are particularly preferred. These are commercially
available in the form of latexes, such as PRIMAL® B-15J and RHOPLEX® N-560 (ex. Rohm
& Haas). When present, any rubber present in the compositions of the present invention
are desirably included in an amount of from about 0.1 to about 5% by weight.
[0059] A further constituent which is optionally, but in certain cases desirably included
in the reaction mixture used to form the foamed polyurethane composition aresilane
based coupling agents, especially alkoxysilane coupling agents. Such coupling agents
are per se, known to the art and include silane coupling agents of both the amino
type and of the glycidyl type. Preferred commercially available alkoxysilane coupling
agents are presently available under the tradename SILQUEST®. When present, silane
based coupling agents are desirably included in an amount of from about 0.1 to about
1.0% by weight, or alternately in an amount of from about 0.01%wt. to about 4%wt.
based on the weight of any bulking agents which may be present.
[0060] In accordance with certain aspects of the invention, a bulking agent, usually a solid
bulking agent is incorporated into reaction mixture and thereby ultimately into the
foamed polyurethane composition. While this is not essential, it is often desirable
to include such a bulking agent to the reaction mixture particularly when a larger
three dimensional foamed article is to form part of the cleaning article according
to the present invention. Such bulking articles are, per se known to the art and especially
are known to the relevant technical field relating to the formation of foam polyurethane
articles. By way of non-limiting examples, such bulking agents include inorganic oxides
and inorganic silicates e.g., wollastonite, pumice, feldspar, diatomaceous earth,
garnet, and the like. When present, the total amount of bulking agent present in the
compositions of the present invention are desirably included in an amount of from
about 0.1 to about 50% by weight.
[0061] As noted previously, when such bulking agents are incorporated, it is also preferred
that at least one silane compund also be included in the reaction mixture containing
the polymer precursor. The silanes are useful as coupling agents for the bulking agents,
particularly where such bulking agents are minerals and thereby facilitate the incorporation
of the bulking agents into the three dimensional structure of the polyurethane foams.
[0062] According to certain particularly preferred embodiments foamed polyurethane compositions
of the present invention and articles comprising said foamed polyurethane compositions
are essentially free of silicon-based surfactants, such as the silicone oils and the
siloxane oxyalkylene block copolymers as described to be an essential constituent
in
US 4476251.
[0063] A still further constituent which may be included in the foamed polyurethane compositions
of the present invention are an acid constituent which be a water soluble inorganic
acid, or a water soluble organic acid or combination thereof. By way of non-limiting
example useful inorganic acids include hydrochloric acid, phosphonic, and sulfuric
acid. With respect to water soluble organic acids, generally include at least one
carbon atom, and include at least one carboxyl group (-COOH) in its structure. Preferred
are water soluble organic acids which contain from 1 to about 6 carbon atoms, and
at least one carboxyl group as noted. Particularly preferred amongst such organic
acids are: formic acid, citric acid, sorbic acid, acetic acid, boric acid, maleic
acid, adipic acid, lactic acid, malic acid, malonic acid, glycolic acid, and mixtures
thereof. According to certain preferred embodiments however, the acid constituent
is a combination of citric acid in combination with at least one further acid selected
from the group consisting of sorbic acid, acetic acid, boric acid, formic acid, maleic
acid, adipic acid, lactic acid, malic acid, malonic acid, and glycolic acid. Most
preferably, the acid constituent a lactic acid. When present, any acids present in
the compositions of the present invention are desirably included in an amount of from
about 0.1 to about 10% by weight.
[0064] The foamed polyurethane composition of the present invention may optionally include
one or more further constituents which may aid in improving the appearance and/or
handling characteristics of the cleaning articles of the invention. Such may be incorporated
into the reaction mixture and are thus incorporated into the polyurethane foam. Where
optional, they are frequently included so to aid in improving the attractiveness of
a cleaning article according to the invention. By way of non-limiting examples, such
further constituents include, coloring agents such as dyes, and pigments, fragrances
whether derived from natural sources, or synthetically produced or both, agents directed
towards the neutralization of the treatment of undesirable odors, and the like.
[0065] As noted above, the foamed polyurethane composition described herein may be used
to form any of a number of cleaning articles. The cleaning article produced according
to the present inventive teaching may take any number of forms and configurations.
Indeed, it is to be understood that the ultimate physical form of the cleaning article
may be varied in accordance with the desired form of the commercial product. By way
of non-limiting example, the cleaning articles according to the invention may take
any shape or forming in order to address a particular need in a cleaning and/or disinfecting
application. Exemplary forms of the cleaning articles of the invention may be any
molded three dimensional shape particularly in the form of a sponge, a sponge head
such as for a mop, as well as a sponge head which may be removable or permanently
affixed to a handle which may be gripped by a consumer. In such a latter configuration,
such a sponge head affixed to a handle can be used in a variety of specialized cleaning
purposes such as for example dishes, pots and pans, and when produced in a larger
size, surfaces such as bathroom surfaces including the interior of toilet bowls. Alternately
the cleaning article according to invention can be of a generally planar configuration
such as in the form of a flexible sheet which can then be used as a wiping article.
Such a flexible sheet is desirably sized so that it can be conveniently used by a
consumer in contacting a surface such as a kitchen, bathroom surfaces, or other hard
surfaces. Alternately the polyurethane foams which exhibit an antimicrobial benefit
can be configured in the form of a ribbon or tape, and such a ribbon or tape can be
used as a cleaning article, or used in the construction of a cleaning article. For
example, a series of loops can be formed from a single piece, or from discrete pieces
of such a ribbon or tape and affixed to a handle in such a way, a "loop brush" can
be formed. Such a loop brush can be conveniently affixed to a handle and used in the
manner described above in the cleaning of hard surfaces particularly kitchen, dishes,
and lavatory surfaces. An advantage of such looped brush is that as opposed to a solid
three dimensional foamed article, the loop brush features a greater degree of flexibility
and that is maybe more appropriate for certain cleaning functions than others.
[0066] With regard to the cleaning articles, it is to be contemplated that further materials
and/or further articles may be associated with the foamed polyurethane composition
which exhibits an antimicrobial benefit. Such alternate materials may take any shape
or form and can include, for example handles, grasping implements, and the like. Further
materials which are particularly advantageously used in certain configurations of
cleaning articles which are considered within the scope of the present invention are
pads, woven sheets, non-woven sheets, abrasive pads, and the like. For example, according
to certain particularly preferred embodiments of a cleaning article according to the
present invention, a non- woven abrasive material, generally in the form of a pad,
is bonded to the foamed polyurethane composition which exhibits an antimicrobial benefit.
While any bonding means can be used,
inter alia, stitching, adhesive, and the like, conveniently such an abrasive article is bonded
to the polyurethane foam during the in-situ polymerization of the foamed polyurethane
composition according to the invention. Such a technique is preferred as there is
formed a physical bond between the polyurethane foam and the abrasive article which
obviates the need for stitching, and or the need for an intermediate adhesive, or
for other additional means which may unnecessarily increase the cost, or require a
further manufacturing step in producing cleaning articles.
[0067] According to a particularly preferred aspect of the invention there is provided a
cleaning article which exhibits an antimicrobial benefit, wherein the foamed polyurethane
article comprises at least one layer of a fibrous substrate bonded to a sponge formed
from the foamed polyurethane composition, and preferably comprises a foamed polyurethane
composition layer layered in register and between two fibrous substrate layers.
[0068] By way of non-limiting examples, useful fibrous substrates can be of a woven or non-woven
nature, and may take a variety of forms. Exemplary useful fibrous substrates can include
nonwoven or woven materials (fabrics), and such substrates can be resin bonded, hydroentanged,
thermally bonded, meltblown, needlepunched or any combination of the former. Such
substrates may be formed form virtually any material including fibrous materials obtained
from synthetic as well as naturally occurring sources. Nonwoven fibrous substrates
are typically preferred from a cost standpoint however, nothing should be understood
to inhibit the use of woven fibrous substates as well.
[0069] Nonwoven fibrous substrates may be a combination of wood pulp fibers and textile
length synthetic fibers formed by well known dry-form or wet-lay processes. Synthetic
fibers such as rayon, nylon, orlon and polyester as well as blends thereof can be
employed, with or without fibers obtained from naturally occurring sources, e.g.,
wood pulp fibers, cellulose and the like. In certain embodiments, the wood pulp fibers
should comprise about 30 to about 60 percent by weight of the nonwoven fabric, preferably
about 55 to about 60 percent by weight, the remainder being synthetic fibers. The
wood pulp fibers provide for absorbency, abrasion and soil retention whereas the synthetic
fibers provide for substrate strength and resiliency.
[0070] Examples of commercially available and particularly useful fibrous substrates include:
Dexter® 10494 which is described to be a 70% viscose / 30% polyolefin blend; Dexter®
5608 which is described to be a 45% cellulose / 55% polyester and polypropylene blend;
Dexter® 12086 which is described to be a 65% cellulose / 30% rayon / 5% synthetic
fiber blend; Dexter® 8553-55 which is described to be approximately 80% cellulose,
20% rayon blend; Dexter® 12131 described to be a 65% cellulose / 30% polyester blend
containing a further 5% of a binder material; Dexter® 10471 which is described to
be a 75% cellulose / 7% rayon / 10% polyester and 8% polyolefin blend; Spuntech® A080
described to be a 70% cellulose / 30% polyester blend; Fiberlla® 4300 described to
be a 50% cellulose / 50% polyester blend; Vicotex® D6M-45 described to be a viscose/polyester
blend; as well as Albad® SP50 described to be a 70% cellulose / 30% polyester blend.
Further and preferred examples of useful fibrous substrates are recited with reference
to one or more of the Examples.
[0071] The fibrous substrates are typically supplied in the form of sheets or wide ribbons
which are generally planar. Certain fibrous substrates including those which are amongst
the preferred embodiments are constructed to provide an abrasive effect when applied
to surfaces. Other fibrous substrates including those which are also amongst the preferred
embodiments include those having a "quilted" pattern wherein regions of the fibrous
substrate extend outwardly from the plane of the fibrous substrate thereby imparting
a three-dimensional appearance.
[0072] A particularly preferred embodiment of a cleaning article according to the invention
is a multilayered cleaning article which comprises a layer of the foamed polyurethane
composition providing an antimicrobial benefit layered in register and between two
fibrous substrate layers, particularly where one of said fibrous substrate layers
is constructed to provide an abrasive effect, while the other said fibrous substrate
layer includes a quilted pattern. Such an embodiment provides dual-function in that
the abrasive layer may be used to improve the removal of soils or other materials
on hard surfaces, while the opposite layer provides good water absorption and an attractive
appearance. While any bonding means can be used,
inter alia, stitching, adhesive, and the like, conveniently the two fibrous substrate layers
are bonded to the intermediate polyurethane foam layer during the in-situ polymerization
of the polyurethane foam.
[0073] In a particular aspect the present invention provides a polyurethane based foam composition,
and articles formed therefrom, which exhibits a residual antimicrobial benefit. Said
residual antimicrobial benefit is a very significant improvement over known-art cleaning
articles. The inventors have found that according to preferred aspects of the invention,
the cleaning articles comprising the foamed polyurethane composition exhibit a residual
antimicrobial benefit even after the cleaning article has been saturated with water,
particularly tap water, and rinsed a number of times. Particularly preferred embodiments
of the invention are wherein a residual antimicrobial benefit is retained even after
the cleaning article has been "rinse/squeeze" a large number of times. By the term
"rinse/squeeze" is meant that the cleaning article is contacted in water to saturation(especially
under a stream of running tap, or deionized water) and thereafter is manually squeezed
or wrung to remove a significant proportion of the water (generally in excess of about
40% by weight) which had been absorbed. The present inventors have surprisingly found
that good residual antimicrobial efficacy is retained in the cleaning articles according
to the present invention.
[0074] According to one particularly preferred aspect of the invention, there is provided
such a cleaning article comprising a foamed polyurethane composition as described
herein which exhibits, following at least fifty(50) rinse/squeeze cycles, an elution
of at least about 100 parts per million, preferably an elution of at least about 150
parts per million of the germicidal quaternary ammonium compounds in the fluid squeezed
or wrung from the article.
[0075] According to another particularly preferred aspect of the invention, there is provided
a cleaning article comprising the foamed polyurethane composition described herein
which exhibits, following at least twenty (20) rinse/squeeze cycles, preferably at
following at least fourth (40)rinse/squeeze cycles an elution of at least about 300
parts per million of the germicidal quaternary ammonium compounds in the water squeezed
or wrung from the article.
[0076] According to a still further particularly preferred aspect of the invention, a cleaning
article comprising the foamed polyurethane composition as described herein which exhibits,
following at least fifty (50) rinse/squeeze cycles an elution of at least about 200
parts per million of the germicidal quaternary ammonium compounds in the water squeezed
or wrung from the article.
[0077] According to a further particularly preferred aspect of the invention there is provided
a cleaning article wherein the maximum thickness of the layer of foamed polyurethane
composition present in a cleaning article is not in excess of about 10 millimeters,
which cleaning article exhibits, following at least ten (10) rinse/squeeze cycles,
more preferably following at least twenty(20) rinse/squeeze cycles, an elution of
at least about 200 parts per million, preferably at least about 300 parts per million,
but more preferably an elution of at least about 400 parts per million of the germicidal
quaternary ammonium compounds in the fluid squeezed or wrung from the article.
[0078] Desirably, effective antimicrobial efficacy can be expressed as the concentration
of germicidal quaternary ammonium compounds which are eluted from the cleaning article
during the squeezing step. The concentration of the eluted quaternary ammonium compounds
can be determined by routine analytical methods.
[0079] The present inventors surprisingly discovered that, in addition to exhibiting a residual
antimicrobial property within the cleaning articles, that preferred embodiments of
the cleaning articles of the invention also exhibit good "contact-kill" when exposed
to an undesirable microorganism, particularly gram negative bacteria e.g.,
Salmonella chnleraesuis and/or gram positive bacteria e.g.
Staphylococcus aureus. Preferred embodiments of the invention demonstrate good antimicrobial efficacy against
Enterobacter aerogenes. Such "contact to kill" is an important feature in a cleaning article, as rapid destruction
of undesired micro-organisms can be achieved. Such as a particularly useful technical
characteristic in a cleaning article in that it is contemplated that frequently, the
same cleaning article is used to treat a variety of surfaces within a particular environment.
For example, in a kitchen it is readily foreseen that a cleaning article can be used
to, for example wash a cutting board or cutting surface, thereafter rinsed, and subsequently
used to manually wash one or more dishes such as in a kitchen sink. The benefits of
rapid kill are that undesired micro-organisms which are trapped or entrained upon
the surface of the cleaning article following treatment of the cutting surface are
rapidly destroyed, and such substantially lowers the likelihood of cross contamination
of any micro-organisms on the cutting board or cutting surface with the surfaces of
the dishes to be manually washed. And such an application, and according to preferred
embodiments of the cleaning article, the cleaning article would first be moistened
with water or with any other cleaning composition and used to wipe the cutting board
or cutting surface, thereafter it is contemplated that it would be rinsed in water,
wrung to remove a majority of the water entrained within the sponge, and thereafter
used to manually wash the dishes. Due to the rapid contact kill, most, if not all
of the undesired micro-organisms which may come into contact from the cutting board
or cutting surface and into the cleaning article would be destroyed or deactivated
prior to coming into contact with the dishes to be manually washed particularly when
the protocol of an intermediate rinsing step is practiced as outlined above.
[0080] According to certain embodiments of the invention, the foamed polyurethane compositions
which exhibit an antimicrobial benefit provide three concurrent technical functions
namely, that of an absorbent carrier, at the same time as a controlled release, and
as a reservoir for the quaternary ammonium compound having germicidal properties.
When contacted with a fluid, particularly water, the solubility exhibited by the quaternary
ammonium compound is limited and thus, only a proportion of the quaternary ammonium
compound leaches out from the foamed polyurethane composition. As compared to prior
art cleaning articles wherein generally most of any water soluble germicidal or sanitizing
agent quickly leaches out after a relatively small number of rinse/squeeze cycles,
surprisingly the quaternary ammonium compounds, particularly the preferred quaternary
ammonium compounds appear to exhibit a strong affinity to the polyurethane foam. This
strong affinity is believed to be a significant factor which provides for a surprisingly
long useful life of the cleaning articles containing the foamed polyurethane compositions
and the residual antimicrobial benefits. While not wishing to be bound by the following,
it is believed that such an affinity exists, and that such an affinity between the
polyurethane of the foamed polyurethane composition, and the quaternary ammonium compound
having germicidal properties is responsible for the ability of the foamed polyurethane
compositions to exhibit a useful antimicrobial benefit even after fifty (50) or even
more rinse/squeeze cycles, and in some cases even after one hundred(100) rinse/squeeze
cycles. While not wishing to be bound by the following it is hypothesized that during
the production of the polyurethane foam the quaternary ammonium compound having germicidal
properties is physically trapped within the cell walls of the polyurethane foam and
this physical entrapment is responsible for the affinity between the polyurethane
foam on the one hand and the quaternary ammonium compound on the other hand. Such
physical entrapment is relatively long lasting, and contributes to the surprisingly
long useful life of the cleaning article formed from or formed using the polyurethane
foams taught herein and the residual antimicrobial benefit observed by the inventors.
[0081] Further, while not wishing to be bound by the following it is hypothesized that the
inclusion of a nonionic block copolymer based on a polymeric ethoxy/propoxy units,
especially PLURONIC® F88 may act to retard, or slow the release of the quaternary
ammonium compound having germicidal properties from within the polyurethane foam.
[0082] The following examples below illustrate exemplary formulations and preferred foamed
polyurethane compositions according to certain aspects of the invention, It is to
be understood that these examples are presented by means of illustration only and
that further useful formulations foamed polyurethane compositions fall within the
scope of this invention and the claims may be readily produced by one skilled in the
art and not deviate from the scope and spirit of the invention. Throughout this specification
and in the accompanying claims, weight percents of any constituent are to be understood
as the weight percent of the active portion of the referenced constituent, unless
otherwise indicated.
Examples
[0083] Exemplary formulations illustrating certain preferred embodiments of foamed polyurethane
compositions which exhibit an antimicrobial benefit according to the invention are
described in more detail in Table 1. These below were formulated generally in accordance
with the following protocol.
[0084] A reaction mixture is formed from two components, the first component being the polyurethane
prepolymer composition, e.g., HYPOL JT6000, and the second component being a premixture
of the remaining constituents. The second component was conveniently formed by combining
its constituent in appropriate measured amounts in a standard laboratory glass beaker
using conventional laboratory stirrer to ensure homogeneity of the second component.
Next measured amounts of the first component and the second component were blended
together using a standard laboratory stirrer using a paddle blade rotating at about
1000 - 9000 rpm for a period of about 1 - 30 seconds, especially between about 1 -10
seconds to ensure good blending of the two components, lmmediately thereafter the
blended mixture was poured into a cavity mold and allowed to react to form a foamed
polyurethane article which exhibits an antimicrobial benefit. Optionally a non-woven
abrasive sheet material was applied to the upper open end of the cavity mold and at
least a part of the surface of the rising polymerized foamed polyurethane article
entangled the non-woven abrasive sheet material and formed a physical bond therewith.
The foamed polyurethane article was thereafter removed from the cavity mold and it
was ready for use.
[0086] The identity of the specific constituents named in Table 1 are identified on Table
2, following:
Table 2 |
Hypol JT6000 |
polyurethane prepolymer preparation (ex. Dow Chemical Co.) |
Catagen T50 |
C8-C18 alkyl dimethyl benzalkonium ammonium chloride (50%wt. actives) in an aqueous carrier
(ex. Stepan) |
BTC-65 |
C12-C16 alkyl dimethyl benzyl ammonium chloride provided in an aqueous alcoholic carrier
(50%wt. actives) (ex. Stepan ) |
BTC-8358 |
C12-C16 alkyl dimethyl benzyl ammonium chloride provided in an in an aqueous alcoholic carrier
(80%wt. actives) |
STC-2125 M90 |
C12-C16 dimethyl benzyl ammonium chloride (45%wt.), C12-C18 alkyldimethyl(ethylbenzyl) ammonium chloride (45%wt.) provided in an aqueous alcoholic
carrier (90% actives) (ex. Stepan) |
benzethonium chloride |
benzyldimethyle[-2-(-2-[p-(1,1,3,3-tetramethylbutyl-)-phenoxy]-ethoxy]-ammonium chloride
monohydrate in powder form (100% actives) (ex. Lonza) |
Hyamine 1622 Crystal |
diisobuylphenoxyethoxyethyl dimethyl benzyl ammonium chloride (50%wt.), inert constituents
(50%wt.) in powder form |
Wollastonite 325 |
calcium silicate (100% actives) (ex Minera NYCO, S.A.) |
Microglass |
mixed oxides of silicon, calcium, aluminum, magnesium and boron fused in an amorphous
vitreous state (100% actives) (ex. Fibertec) |
Feldspar |
aluminum silicate containing various amounts of sodium, potassium, and calcium (100%
actives) (ex. Feldspar Corp.) |
Tomadol 91-6 |
C9-C11 alcohol ethoxylate (100% actives) (ex. Tomah) |
Silquest A1120 |
At least 70% of N-beta-(aminoethyl)-gamma-amine propyltrimethoxysilane, less than
30%wt. of siloxanes and silane esters, the balance being methanol and ethylene diamine
(100%wt. actives) (ex. OSi) |
Pluronic F88 |
polyethylene/polypropylene block copolymer (a 10% solution of the polyethylene/polypropylene
block copolymer of avg. molecular weight of 11400 dispersed in 90% water) (ex. BASF) |
Pluronic F98 |
polyethylene/polypropylene block copolymer (a 10% solution of the polyethylene/polypropylene
block copolymer of avg. molecular weight of 13000 dispersed in 90% water) (ex. BASF) |
Pluronic F108 |
polyethylene/polypropylene block copolymer (a 10% solution of the polyethylene/polypropylene
block copolymer of avg. molecular weight of 14600 dispersed in 90% water) (ex. BASF) |
Pluronic F127 |
polyethylene/polypropylene block copolymer (a 10% solution of the polyethylene/polypropylene
block copolymer of avg. molecular weight of 12600 dispersed in 90% water) (ex. BASF) |
Dowanol DPnB |
dipropylene glycol n-butyl ether (100%) (ex. Dow Chemical Co.) |
fragrance |
proprietary composition |
colorant |
a premixture containing 0.79%wt. of Pluronic F88 (neat), 20%wt. of a green pigment,
and 0.2%wt. of Silquest A1120, with the balance to 100%wt. being water. |
Purac Sanilac Acid |
L(+)-lactic acid in aqueous solution (80%wt. actives) |
deionized water |
deionized water |
[0087] The form of the sponges produced from the foamed polyurethane compositions described
on Table 1 are illustrated on Figure 1. As is visible, the sponge 10 comprises two
parts, a body 12 of a polyurethane foam formed from the compositions described on
Table 1, said body 12 having an upper curved surface 13 layered in register with a
layer of a non-woven abrasive sheet material 14 contacting a lower flat surface 15
of the body 12.
Elution of germicidal quaternary ammonium compounds from cleaning articles
[0088] Several test sponges having compositions as described on Table 1 were saturated in
water by holding under a stream of deionized water and thereafter each test sponge
was manually squeezed or wrung to remove a significant proportion of the water (generally
in excess of about 40% by weight, preferably at leas 50% by weight, more preferably
at least about 75% by weight) which had been absorbed. Each such operation was a "squeeze/wring
cycle." Each test sponge was evaluated for a sequence of squeeze/wring cycles and
the amount of quaternary ammonium compound in the eluted water was evaluated according
to conventional laboratory methods. The results are deported below; the amounts of
the quaternary ammonium compound in the eluted water is indicated in parts per million
(ppm) following the indicated number of squeeze/wring cycles.
Example 1 |
|
20 squeeze/wing cycles |
340 ppm |
50 squeeze/wring cycles |
113 ppm |
Example 2 |
20 squeeze/wring cycles |
368 ppm |
40 squeeze/wring cycles |
340 ppm |
50 squeeze/wring cycles |
283 ppm |
40 squeeze/wring cycles |
142 ppm |
Example 13 |
20 squeeze/wring cycles |
566 ppm |
40 squeeze/wring cycles |
368 ppm |
50 squeeze/wring cycles |
340 ppm |
100 squeeze/wring cycles |
198 ppm |
120 squeeze/wring cycles |
170 ppm |
Example 14 |
20 squeeze/wring cycles |
541 ppm |
40 squeeze/wring cycles |
361 ppm |
50 squeeze/wring cycles |
252 ppm |
100 squeeze/wring cycles |
361 ppm |
120 squeeze/wring cycles |
216 ppm |
140 squeeze/wring cycles |
144 ppm |
Antimicrobial Evaluation
Test Microorganism:
[0089] The microorganism used for the antimicrobial evaluation of cleaning articles was
Enterobacter aerogenes (ATCC# 13048).
Preparation of test sponges:
[0090] Each of the tested cleaning articles were formed sponges having a mass of approximately
31 - 37 grams. The compositions of the test sponges are described on Table 1. Each
test sponge was aseptically removed from its packaging and stored in a large, sterile
Petri dish. Each Petri dish (also referred to as "plates" herein) was uniquely labeled
to identify the test sponge contained within. Between assays, and when not in use
for testing, the large Petri dishes containing each of the test sponges was stored
in a laminar flow hood.
[0091] For the antimicrobial evaluation of test sponges, three replicates (3 separate sponges)
of a test sponge composition were used.
Preparation of the test system (culture transfer):
[0092] From a stock culture (e.g. a frozen culture), a transfer was performed into an appropriate
growth media, and incubated at 35+2.5°C overnight. This transfer was labeled To for
Enterobacter aerogenes, and the cultures were incubated at 30°C.
[0093] Three consecutive 24-hour culture transfers were performed, and sequentially labeled
as T1.T2, and T3.
[0094] After this 3rd transfer, one daily broth transfer was skipped. For further transfers
beyond the 3rd transfer "T3"e.g., up to and including an eight transfer identified
as "T8", an aliquot (e.g. 100mL bottle, 350mL flask) of growth broth was inoculated
at a ratio of 1: 1000. Similarly, transfers were inoculated and incubated overnight
at 30+1.0°C to obtain the E. aerogenes test inoculum.
Preparation of Test Culture(s):
[0095] The test inoculum was poured through a sterile funnel containing coarse filtration
medium (e.g. glass wool) to remove any particulate matter.
[0096] An appropriate amount of the filtered culture was pipetted into a sterile vessel
and a sufficient volume of organic soil, horse serum, was added to achieve a final
concentration of 5% (v/v). Any combination of culture/organic soil (e.g. 9.5 mL/0.5
mL) that results in a final concentration of 5% organic soil was considered acceptable.
The prepared mixtures were vortexed; thereafter these prepared mixtures were referred
to as "test culture" (or "test cultures").
Inoculation of the Test Surface:
[0097] On each assay day, for each sponge tested, four sterile 100mm Petri dishes were used.
A 2½ square was inscribed on the bottom exterior of each Petri dish. For each tested
sponge replicate, each of the four Petri dishes were labeled with the identity of
the tested sponge, and either a 1, 2, 3 or R.
[0098] Plate 1 was inoculated with 0.01 to 0.03 mL of the test system and dried, and was
used to soil the test sponge.
[0099] Plate 2 was inoculated with 0.01 to 0.03 mL of the test system and was used to assay
the sanitization efficacy of liquid eluted from the test sponge.
[0100] Plate 3 was inoculated with 0.01 to 0.03 mL of the test system and was used to assay
the sanitization efficacy of the test sponge after it is used to wipe the test surface.
[0101] Plate R was not inoculated and was used to assay the amount of bacteria redeposited
after wiping the test sponge after the previous steps of were performed.
[0102] For each test system, 3 additional plates marked with a 2 ½ square were also inoculated
and dried. These plates serve as "dried recovery count plates."
[0103] (For example, if 8 tested cleaning article replicates are being tested for Enterobacter
aerogenes, then a total of 27 plates were be inoculated, viz, 3 plates per tested
cleaning article replicate plus 3 dried recovery count plates).
[0104] The total number of plates per test system may have been inoculated and dried all
at once, or dried in sets depending on the testing plan or schedule. Dried recovery
count plates were usually assayed last to truly reflect the number of organisms surviving
the incubator drying as well as any additional drying that occurred while sitting
on the laboratory benchtop.
Carrier drying:
[0105] The inoculated test plates were dried at 35+2.5°C for 15-20 minutes. Drying temperatures
outside of this range, and for a longer period of time, was considered acceptable
if the assay recovery control counts were within the expected and acceptable ranges.
After this drying period, the complete drying of the test culture on all of the test
plates (Petri dishes) was ensured.
Treatment of the test system with the test sponge:
[0106] Each test sponge was tested in the following manner on each assay date.
[0107] Wearing a new set of sterile gloves for each tested cleaning article, the tester
(technician) held the test sponge under lukewarm running water (approximately 80 to
105°F/ 26.7 to 40.5°C) provided from a municipal water source, viz., tap water. The
test sponge was then squeezed to remove any excess water. This rinsing and squeezing
(rinse/squeeze cycle) simulated the wetting of the test sponge and squeezing out of
excess water prior to use in the household. This rinse/squeeze sequence was performed
3 times.
[0108] After the 3rd squeeze, the test sponge was used to wipe the inoculated bottom of
Plate I (Petri dish) for 2-3 seconds. This step represented a periodic challenge with
a microbiological bioburden (viable test bacteria dried onto surfaces/carriers which
are wiped.)
[0109] An additional sequence of 7 tap water rinses/squeezes was performed. After the 10th
daily rinse/squeezes was performed, the liquid from the test sponge was eluted onto
the inoculated surface of Plate 2; this inoculated plate was not thereafter wiped.
[0110] Thereafter, the inoculated surface of Plate 3 was then wiped with the test sponge
for 5 seconds.
[0111] A contact time of "X" was initiated from Plate 2 and Plate 3.
[0112] The bottom sterile surface of Plate R was then wiped with the test sponge to assess
for any redeposition. Twenty (20) mL of neutralizer may have been added to Plate R
immediately after wiping.
[0113] At the contact time of "X", 20 mL of neutralizer broth was poured onto the test surfaces
of Plates 2 and 3. A cell scraper was used to resuspend any organisms remaining on
the surfaces of Plates 2 and 3. Thereafter serial dilutions from each plate (Plates
2,3 and R) were performed, and the appropriate dilutions were plated, in a conventional
manner.
[0114] This sequence was repeated several times utilizing the same test sponge, so that
the performance of a test sponge over a sequence of days, with 10 rinse/squeeze cycles
performed on each assay day, could be evaluated. The sequence was performed on sequential
calendar days, as well as non-sequential calendar days where days were omitted, e.g.,
wherein the testing was not performed over two weekend days, but resumed during the
following work week.
Serial dilutions and plating:
[0115] Test Plates 2, 3 and R were considered the 100 dilution. Dilutions of 100, 101 and
102 were plated for each tested cleaning article replicate. Dilutions of 100, 101
and 102 were plated for the test substance replicates. Dilutions of 101, 102 and 103
were plated for any "control" replicates. Dilutions of 101, 102 and 103 were plated
for the dried recovery control replicates. One (1) mL aliquots of each dilution were
plated, and poured with Trypticase Soy Agar ("TSA").
Incubation:
[0116] The test surfaces contacted with E. aerogenes were incubated at 30+1.0°C for over
2 nights; incubation in excess of 2 nights is acceptable as long as the culture media
was not dehydrated.
Quantitation of results:
[0117] The number of survivors present on the plates were quantitated and the resulted recorded.
The results indicated below indicate the averaged results for the 3 replicates of
the test sponges. The sequence of the days is indicated in order of calendar days,
which may not be sequential. In the tables below, the results in the column indicated
as "L" indicated the number of colonies of surviving Enterobacter aerogenes present
on the plate (Plate 2) onto which the liquid was eluted from the test sponge, the
results in the column indicated as "W" indicated the number of survivors present on
the plate (Plate 3) which was wiped with the test sponge, the results in the column
indicated as "R" indicated the number of survivors present on the plate (Plate R)
which was wiped in order to assay the redeposition of Enterobacter aerogenes. The
minimum threshold in determining the number of survivors present on a plate was 20
survivors; any value less than 20 ("<20") indicated extremely effective eradication
of Enterobacter aerogenes on a plate.
Test Sponge according to Example 1 |
Calendar Day |
Total number of rinse/squeeze cycles |
L |
W |
R |
1 |
10 |
<20 |
<20 |
<20 |
2 |
20 |
<20 |
<20 |
<20 |
3 |
30 |
<20 |
<20 |
<20 |
4 |
40 |
806 |
<20 |
<20 |
7 |
50 |
<20 |
<20 |
<20 |
8 |
60 |
<20 |
<20 |
<20 |
9 |
70 |
<20 |
<20 |
<20 |
10 |
80 |
<20 |
<20 |
<20 |
11 |
90 |
<20 |
<20 |
<20 |
14 |
100 |
<20 |
<20 |
<20 |
Test Sponge according to Example 13 |
Calendar Day |
Total number of rinse/squeeze cycles |
L |
W |
R |
1 |
10 |
<20 |
<20 |
<20 |
2 |
20 |
<20 |
<20 |
<20 |
3 |
30 |
<20 |
<20 |
<20 |
4 |
40 |
<20 |
<20 |
<20 |
7 |
50 |
<20 |
<20 |
<20 |
8 |
60 |
<20 |
<20 |
<20 |
9 |
70 |
<20 |
<20 |
<20 |
10 |
80 |
<20 |
<20 |
<20 |
11 |
90 |
<20 |
<20 |
<20 |
14 |
100 |
<20 |
<20 |
<20 |
15 |
110 |
<20 |
<20 |
<20 |
16 |
120 |
<20 |
13.3 |
<20 |
18 |
130 |
<20 |
587 |
<20 |
21 |
140 |
<20 |
<20 |
<20 |
22 |
150 |
<20 |
<20 |
<20 |
23 |
160 |
<20 |
<20 |
<20 |
29 |
170 |
<20 |
<20 |
<20 |
30 |
180 |
<20 |
40 |
<20 |
Test Sponge according to Example 14 |
Calendar Day |
Total number of rinse/squeeze cycles |
L |
W |
R |
1 |
10 |
<20 |
<20 |
<20 |
2 |
20 |
<20 |
<20 |
<20 |
3 |
30 |
<20 |
<20 |
<20 |
4 |
40 |
<20 |
<20 |
<20 |
5 |
50 |
<20 |
<20 |
<20 |
8 |
60 |
<20 |
<20 |
<20 |
9 |
70 |
<20 |
<20 |
<20 |
10 |
80 |
<20 |
<20 |
<20 |
12 |
90 |
<20 |
<20 |
<20 |
15 |
100 |
<20 |
<20 |
<20 |
16 |
110 |
<20 |
<20 |
<20 |
17 |
120 |
<20 |
<20 |
<20 |
23 |
130 |
<20 |
33.3 |
<20 |
24 |
140 |
<20 |
<20 |
<20 |
25 |
150 |
<20 |
<20 |
<20 |
30 |
160 |
2.78 (104) |
<20 |
<20 |
32 |
170 |
<20 |
<20 |
<20 |
33 |
180 |
<20 |
60 |
<20 |
[0118] As can be seen from the foregoing, the tested cleaning articles (test sponges) produced
according to the inventive teaching exhibited a good residual antimicrobial benefit
is retained even after the cleaning article has been rinse/squeeze cycled a large
number of times.
Multilayered cleaning article
[0119] A multilayered cleaning article as depicted on Figures 2A and 2B comprising a layer
of a foamed polyurethane composition according to the invention layered in register
with a first abrasive fibrous substrate layer was produced.
[0120] A first sheet of an abrasive non-woven material was applied onto a flat laboratory
benchtop and sprayed with approximately 10-12 grams of form release agent, LPS Heavy
Duty Silicone Lubricant. The purpose of the form release agent was to ensure that
the first sheet of abrasive non-woven material could be ultimately peeled away from
the formed sponge article. Next, a reaction mixture is formed from two components,
the first component being the polyurethane prepolymer composition, e.g., HYPOL JT6000,
and the second component being a premixture of the remaining constituents all of which
arc identified on Table 3, following. The second component was conveniently formed
by combining its constituents in appropriate measured amounts in a standard laboratory
glass beaker using conventional laboratory stirrer to ensure homogeneity of the second
component. Advantageously the second component is first formed by first providing
the water to a suitable vessel, using a laboratory stirrer the Wollastonite 325 is
added until a suspension is formed, followed by the Silquest 1120 which is allowed
to mix approximately 10-20 minutes a homogenous mixture is attained, followed by the
Tomadol 91-6, then Pluronic F88, then fragrance, then dye, followed by the Dowanol
DPnB, and ultimately the BTC 65 and following the addition of the final constituent
mixing is allowed to continue for further 20 minutes. Next measured amounts of the
first component and the second component were blended together using a standard laboratory
stirrer using a paddle blade rotating at about 1000 - 9000 rpm for a period of about
1 - 30 seconds, especially between about 1-10 seconds to ensure good blending of the
two components.
[0121] Immediately thereafter the blended mixture was poured and evenly spread using a thin
flat blade onto the surface of the sprayed, abrasive non-woven material. Foaming initiated
and approximately 5 - 30 seconds after initiation of foaming but before the conclusion
of the foaming reaction, excess foam was removed using the thin flat blade and thereafter
a further non-woven fibrous substrate material (SAB 36D-45-B) was applied directly
to the exposed polyurethane foam and thereafter a flat plate was applied onto the
further non-woven fibrous substrate material layer. The flat plate was spaced apart
from the said flat surface contacting the non-woven fibrous substrate material via
a series of spacer elements which ensured that the flat surface was approximately
parallel to the plate. After the conclusion of the foaming reaction (approx. 3 - 7
minutes) the plate was removed; the first sheet of an abrasive non-woven material
was peeled away to expose the polyurethane foam surface opposite to that of the further
non-woven fibrous substrate material. Thereafter the first the resultant multilayered
construction was cut into square shapes of approximately 5 ¼ inches by 5 ¼ inches
with the ultimate thickness of these dual-layered flexible wiping articles approximately
2-10 millimeters.
[0122] The ultimate composition of the foamed polyurethane composition layer of the multilayered
cleaning article was as follows:
Table 3 |
Commercial name |
%wt. |
HYPOL JT6000 |
30.30 |
Wollastonite 325 |
27.88 |
SILQUEST 1120 |
0.28 |
BTC-65 |
6.97 |
TOMADOL 91-6 |
2.09 |
PLURONIC F88 |
0.70 |
DOWANOL DPnB |
3.73 |
coloring agent |
0.01-0.1 |
fragrance |
0.31 |
deionized water |
q.s. |
[0123] The identity of the specific constituents are described on Table 2, supra.
[0124] The multilayered cleaning article described herein may also be produced by a continuous
casting process in place of the batch type process recited above.
[0125] With reference now to Figures 2A and 2B, there is depicted a preferred embodiment
of a multilayered cleaning article 20 which is depicted in two views, illustrating
the relationship of the polyurethane foam layer 22 layered in register with the layer
of a non-woven fibrous substrate material 24. No intermediate adhesive material or
layer is required, and the hexagonal shape provides a comfortable gripping surface,
facilitating convenient use by a consumer. Such a preferred embodiment differs from
the resultant multilayered construction described immediately above only due to the
fact that it is cut into a hexagonal shape as opposed to a square shape.
[0126] The elution of the germicidal quaternary ammonium compounds in the water squeezed
or wrung from the 5 ¼ inch by 5 ¼ inch dual-layered flexible wiping articles formed
according to the process described above were evaluated according to the following
general protocol. For the evaluation, three samples (replicates), respectively "A",
"B" and "C" of dual-layered flexible wiping articles formed as described above and
including the composition of Table 3 were tested.
[0127] Testing of each sample was in accordance with the following general protocol: Each
sample was first wetted by a five second contact with a flow of room temperature (approx.
20°C) deionized water flowing from a 5 gallon laboratory dispenser. After the 5 second
exposure, the sample was withdrawn and held at one edge so that the replicate was
oriented vertically and allowed to drain, thereafter the sample was hand-squeezed
to remove at least 50% of the absorbed water and the released eluted liquid was collected
and subsequently analyzed for content of eluted quaternary ammonium compounds. This
procedure was repeated using the same sample of the dual-layered flexible wiping articles
for 100 such squeeze/wring cycles and samples of the released eluted liquid were collected
from the 1st, 10th, 20th, 30th, 40th, 50th, 60th, 70th, 80th, 90th and 100th squeeze/wring
cycles.
[0128] The quantity of eluted germicidal quaternary ammonium compounds were evaluated by
a standard analytical technique via titration utilizing a tetraphenylborate solution.
Of course other analytical techniques may be used and are expected to provide comparable
results.
[0129] The quantity of eluted germicidal quaternary ammonium compounds expressed as parts
per million (ppm) from each of samples A, B and C are indicated on the following Table
4A which indicates the individual results following the respectively indicated squeeze/wring
cycle as well as averaged results for all three samples.
Table 4A |
|
eluted germicidal quaternary ammonium compounds (ppm) |
squeeze/wring cycle |
Sample A |
Sample B |
Sample C |
Averaged results |
1 |
2322 |
2832 |
2407 |
2520 |
10 |
850 |
793 |
906 |
850 |
20 |
425 |
538 |
510 |
491 |
30 |
312 |
340 |
453 |
368 |
40 |
283 |
312 |
368 |
321 |
50 |
283 |
283 |
255 |
274 |
60 |
198 |
255 |
227 |
227 |
70 |
113 |
198 |
198 |
170 |
80 |
113 |
113 |
142 |
123 |
90 |
85 |
85 |
113 |
94 |
100 |
57 |
57 |
57 |
57 |
[0130] As can be seen from the foregoing the samples of the dual-layered flexible wiping
articles provide excellent and long-lasting elution of the germicidal quaternary ammonium
compounds.
Tri-layered cleaning article (1)
[0131] A tri-layered cleaning article as depicted on Figures 3A, 3B and 3C comprising a
layer of a foamed polyurethane composition layered in register and between a first
abrasive fibrous substrate layer and a second fibrous substrate layer including a
quilted pattern was produced.
[0132] First, a sheet of a non-woven fibrous substrate material (Dexter® 10494 having a
"quilted" surface) was applied to a flat laboratory benchtop. Subsequently a reaction
mixture was formed from two components, the first component being the polyurethane
prepolymer composition, e.g., HYPOL JT6000, and the second component being a premixture
of the remaining constituents all of which are identified on Table 4, following. The
second component was conveniently formed by combining its constituents in appropriate
measured amounts in a standard laboratory glass beaker using conventional laboratory
stirrer to ensure homogeneity of the second component. Advantageously the second component
is first formed by first providing the water to a suitable vessel, using a laboratory
stirrer the Wollastonite 325 is added until a suspension is formed, followed by the
Silquest 1120 which is allowed to mix approximately 10-20 minutes a homogenous mixture
is attained, followed by the Tomadol 91 -6, then Pluronic F88, then fragrance, then
dye, followed by the Dowanol DPnB, and ultimately the BTC 65 and following the addition
of the final constituent mixing is allowed to continue for further 20 minutes. Next
measured amounts of the first component and the second component were blended together
using a standard laboratory stirrer using a paddle blade rotating at about 1000 -
9000 rpm for a period of about 1 - 30 seconds, especially between about 1-10 seconds
to ensure good blending of the two components.
Immediately thereafter the blended mixture was poured and evenly spread using a thin
flat blade onto the surface of the abrasive non-woven fibrous substrate. Foaming initiated
and approximately 5 - 30 seconds after initiation of foaming but before the conclusion
of the foaming reaction, excess foam was removed using the thin flat blade and thereafter
a sheet of an abrasive non-woven fibrous substrate material (VICOTEX D6M-45) was applied
directly to the exposed polyurethane foam and thereafter a flat plate was applied
onto the second non-woven fibrous substrate material layer. The flat plate was spaced
apart from the said flat surface contacting the non-woven fibrous substrate material
via a series of spacer elements which ensured that the flat surface was approximately
parallel to the plate. After the conclusion of the foaming reaction (approx. 5 - 7
minutes) the plate was removed; the resultant tri-layered construction was cut into
hexagonal shapes of approximately 5 inches by 6 inches, and the ultimate thickness
of the flexible wiping article was approximately 2-8 millimeters. The ultimate composition
of the foamed polyurethane composition layer of the multilayered cleaning article
was as follows:
Table 5 |
Commercial name |
%wt. |
HYPOL JT6000 |
30.30 |
Wollastonite 325 |
27.88 |
SILQUEST 1120 |
0.28 |
BTC-65 |
6.97 |
TOMADOL 91-6 |
2.09 |
PLURONIC F88 |
0.70 |
DOWANOL DPnB |
3.73 |
coloring agent |
0.01-0.1 |
fragrance |
0.31 |
deionized water |
q.s. |
[0133] The identity of the specific constituents are described on Table 2, supra.
[0134] The multilayered cleaning article described herein may also be produced by a continuous
casting process in place of the batch type process recited above.
[0135] A further embodiment of tri-layered cleaning article 30 is depicted on Figures 3A,
3B and 3C. In this side-plan view there is depicted a foamed polyurethane layer 32
layered in register and between a first abrasive fibrous substrate layer 34 and a
second fibrous substrate layer 36 comprising a quilted pattern having raised regions
38 bounded by recessed regions 40 which recessed regions are bonded to the foamed
polyurethane layer 32 while the raised regions 38 are not. Such a construction defines
cavities 42 between the surface of the foamed polyurethane layer 32 and the raised
regions 38, as bounded by the portion of the recessed regions 40 of the fibrous layer
36 not adhered to the foamed polyurethane layer. Such an embodiment is preferred as
it provides to the consumer two different types of surfaces, e.g., an abrasive non-woven
wipe surface, and a more absorbent "quilted" non-woven wipe surface as integral parts
of the cleaning article, providing a choice to the consumer as to which surface is
more appropriately used for particular use e.g., for the treatment of a particular
surface or removal of a particular type of stain. For example more difficult to use
inorganic deposits such as mineral salts may be more aggressively removed using the
fibrous abrasive substrate layer 34, while general treatment of non-stained surface
or absorption of a spilled liquid might be more appropriately treated using the obverse
side and use of the more absorbent "quilted" non-woven wipe surface. It is to be understood
that while not visible in Figure 3, the preferred form of the depicted wipe is a hexagonal
format such as shown in Figures 2A and 2B, as well as in Figures 3A, 3B and 3C although
other formats and configurations are also considered to be suitable for use as well.
[0136] The inventors have also found that the formation of a cleaning article which does
require formation in a mold, such as the embodiment of Figure 1 avoids the likelihood
that during the foaming reaction the region of the polyurethane sponge contacting
a smooth mold surface does not unduly densify adjacent to such a smooth mold surface
and form a dense outer layer, conveniently referred to as a "skin" layer. The presence
of such a skin layer is generally to be avoided as such both resists the absorption
and elution of liquids through such a skin layer which may inhibit the elution of
the germicidal quaternary ammonium compounds from the cleaning article. Further the
inventors have observed that over prolonged use this skin layer often ruptures or
cracks which lends an unsightly appearance to the product.
[0137] Thus the forms of the multilayer cleaning articles depicted on Figures 2A and 2B
as well as Figure 3A, 3B and 3C are preferred. In accordance with the protocol for
the manufacture of the article depicted on Figures 2A and 2B the use of a first layer
of a non-woven material coated with a mold release lubricant permits for the removal
of said non-woven material following the conclusion of the foaming reaction which
removes any skin layer which may have formed. Of course other techniques such as splitting
or cutting away the skin layer may also be practiced with similar beneficial effect
as well. The embodiment according to Figures 3A, 3B and 3C is to be even more preferred
as the presence of the two layers of non-woven material which contact the polyurethane
foam during the foaming reaction deny the formation of a skin layer, rather the foaming
polyurethane bonds to the non-woven material thereby avoiding the need for any intermediate
adhesive and denying the formation of a skin layer.
Tri-layered cleaning article (2)
[0138] A further embodiment of tri-layered cleaning article comprising a layer of foamed
polyurethane composition layered in register and between a first abrasive fibrous
substrate layer and a second fibrous substrate layer using the protocol described
above with reference to the tri-layered cleaning article (1), and using the same formulation
described on Table 4. In the present tri-layered cleaning article, a first sheet of
a non-woven fibrous substrate material (Ahlstrom 150 GMS) having an embossed quilted
surface with raised regions, and further sheet of an abrasive non-woven fibrous substrate
material (SAB D6-MB50B) was used in place of the respective substrate materials recited
with reference to the tri-layered cleaning article (1). The resultant tri-layered
cleaning article formed was cut into hexagonal shapes of approximately 5 inches by
7 inches, and the ultimate thickness of the flexible wiping article was approximately
2-8 millimeters, as depicted on Figures 3A, 3B and 3C.
Tri-layered cleaning article (3)
[0139] A further embodiment of tri-layered cleaning article comprising a layer of foamed
polyurethane composition layered in register and between a first abrasive fibrous
substrate layer and a second fibrous substrate layer using the protocol described
above with reference to the tri-layered cleaning article (1), and using the same formulation
described on Table 4. In the present tri-layered cleaning article, a first sheet of
a non-woven fibrous substrate material (supplied by ADS Texel) and further sheet of
an abrasive non-woven fibrous substrate material (SAB D6-MB50B) was used in place
of the respective substrate materials recited with reference to the tri-layered cleaning
article (1). The resultant tri-layered cleaning article formed was cut into hexagonal
shapes of approximately 5 inches by 7 inches, and the ultimate thickness of the flexible
wiping article was approximately 2-8 millimeters, as depicted on Figures 3A, 3B and
3C.
Tri-layered cleaning article (4)
[0140] A further embodiment of tri-layered cleaning article comprising a layer of the foamed
polyurethane composition layered in register between a first abrasive fibrous substrate
layer and a second fibrous substrate layer using the protocol described above with
reference to the tri-layered cleaning article (1), and using the same formulation
described on Table 4. In the present tri-layered cleaning article, a first sheet of
a non-woven fibrous substrate material (Ahlstrom 125 GSM, LSW Substrate, thermally
bonded with a further non-woven pad) and further sheet of an abrasive non-woven fibrous
substrate material (SAB D6-MB50B) was used in place of the respective substrate materials
recited with reference to the tri-layered cleaning article (1). The resultant tri-layered
cleaning article formed was cut into symmetrical hexagonal shapes measuring 5 inches
between opposite vertices, and the ultimate thickness of the flexible wiping article
was approximately 2-8 millimeters, as depicted on Figures 3A, 3B and 3C.
Tri-layered cleaning article (5)
[0141] A further embodiment of tri-layered cleaning article comprising a foamed polyurethane
composition layer layered in register and between a first abrasive fibrous substrate
layer and a second fibrous substrate layer using the protocol described above with
reference to the tri-layered cleaning article (1), and using the same formulation
described on Table 4. In the present tri-layered cleaning article, a first sheet of
a non-woven fibrous substrate material (Ahlstrom 125 GSM, LSW Substrate, thermally
bonded with a further non-woven pad) and further sheet of an abrasive non-woven fibrous
substrate material (SAB D6-MB50B) was used in place of the respective substrate materials
recited with reference to the tri-layered cleaning article (1). The resultant tri-layered
cleaning article formed was cut into a hexagonal shape measuring 5 inches in maximum
width, and 6 inches in maximum height, and the ultimate thickness of the flexible
wiping article was approximately 2-8 millimeter, as depicted on Figures 3A, 3B and
3C.
Tri-layered cleaning article (6)
[0142] A further embodiment of tri-layered cleaning article comprising a layer foamed polyurethane
composition layered in register and between a first abrasive fibrous substrate layer
and a second fibrous substrate layer described above with reference to the tri-layered
cleaning article (1), and using the same formulation described on Table 4. In the
present tri-layered cleaning article, a first layer of a non-woven fibrous substrate
material (Ahlstrom 125 GSM, LSW Substrate, thermally bonded with a further non-woven
pad) and further layer of an abrasive non-woven fibrous substrate material (SAB D6-MB50B)
was used in place of the respective substrate materials recited with reference to
the tri-layered cleaning article (1). The tri-layered cleaning article (6) was produced
using a continuous manufacturing process wherein a quantity of the first and second
constituents used to form the foamed polyurethane layer were applied to the surface
of a moving web of the first layer of a non-woven fibrous substrate material, and
subsequently the further layer of abrasive non-woven fibrous substrate material was
applied thereto in order to form the tri-layered cleaning article. Following the cessation
of the foaming of the polyurethane layer, the resultant tri-layered cleaning article
was subsequently cut into a hexagonal shape measuring 5 inches in maximum width, and
6 inches in maximum height, and the ultimate thickness of the flexible wiping article
was approximately 2-8 millimeters, as depicted on Figures 3A, 3B and 3C.
[0143] The elution of the germicidal quaternary ammonium compounds in the water squeezed
or wrung from tri-layered flexible wiping articles formed and described immediately
above as tri-layered cleaning articles (2), (3), (4), (5), and (6) were evaluated
according to the following general protocol. For the evaluation, a single sample of
each aforesaid tri-layered cleaning article was used.
[0144] Testing of each sample was in accordance with the following general protocol: Each
sample was first wetted by a five second contact with a flow of room temperature (approx.
20°C) deionized water flowing form a 5 gallon laboratory dispenser. After the 5 second
exposure, the sample was withdrawn and held at one edge so that the sample was oriented
vertically and allowed to drain, thereafter the sample was hand-squeezed to remove
at least 50%wt. of the absorbed water and the released eluted liquid was collected
and subsequently analyzed for content of eluted quaternary ammonium compounds. This
procedure was repeated using the same sample of the dual-layered flexible wiping articles
for 100 such squeeze/wring cycles and samples of the released eluted liquid were collected
from the 1st, 2nd, 10th, 20th, 30th, 40th, 50th, 60th, 70th, 80th, 90th and 100th
squeeze/wring cycles.
[0145] The quantity of eluted germicidal quaternary ammonium compounds were evaluated by
a standard analytical technique via titration utilizing a tetraphenylborate solution.
Of course other analytical techniques may he used and are expected to provide comparable
results.
[0146] The quantity of eluted germicidal quaternary ammonium compounds expressed as parts
per million (ppm) are indicated on the following Table 4B which indicates the individual
results following the respectively indicated squeeze/wring cycle for each tested sample.
Table 4B |
|
eluted germicidal quaternary ammonium compounds (ppm) |
squeeze/wring cycle |
Tri-layered cleaning article (2) |
Tri-layered cleaning article (3) |
Tri-layered cleaning article (4) |
Tri-layered cleaning article (5) |
Tri-layered cleaning article (6) |
1 |
821 |
1643 |
1643 |
1529 |
1643 |
2 |
1784 |
1756 |
1812 |
1812 |
1756 |
10 |
1246 |
850 |
736 |
1246 |
1048 |
20 |
632 |
623 |
510 |
878 |
453 |
30 |
481 |
510 |
396 |
453 |
396 |
40 |
340 |
425 |
368 |
340 |
368 |
50 |
312 |
340 |
340 |
283 |
340 |
60 |
283 |
283 |
283 |
227 |
312 |
70 |
255 |
255 |
227 |
198 |
283 |
80 |
227 |
198 |
198 |
170 |
255 |
90 |
198 |
170 |
170 |
170 |
198 |
100 |
113 |
142 |
113 |
142 |
198 |
[0147] As can be seen from the foregoing the samples of the tri-layered flexible wiping
articles provide excellent and long-lasting elution of the germicidal quaternary ammonium
compounds.
While the invention is susceptible of various modifications and alternative forms,
it is to be understood that specific embodiments thereof have been shown by way of
example in the drawings which are not intended to limit the invention to the particular
forms disclosed; on the contrary the intention is to cover all modifications, equivalents
and alternatives falling within the scope and spirit of the invention as expressed
in the appended claims.