U.S. patent application number 12/114355 was filed with the patent office on 2008-11-06 for composition for in situ manufacture of insoluble hydroxide when cleaning hard surfaces and for use in automatic warewashing machines and methods for manufacturing and using.
This patent application is currently assigned to ECOLAB INC.. Invention is credited to Kristen A. Mills, Lee J. Monsrud, Keith E. Olson, Michael Rischmiller, Kim R. Smith.
Application Number | 20080274932 12/114355 |
Document ID | / |
Family ID | 39939966 |
Filed Date | 2008-11-06 |
United States Patent
Application |
20080274932 |
Kind Code |
A1 |
Smith; Kim R. ; et
al. |
November 6, 2008 |
COMPOSITION FOR IN SITU MANUFACTURE OF INSOLUBLE HYDROXIDE WHEN
CLEANING HARD SURFACES AND FOR USE IN AUTOMATIC WAREWASHING
MACHINES AND METHODS FOR MANUFACTURING AND USING
Abstract
A composition useful in hard surface treatment and particularly
useful in automatic warewashing is provided according to the
invention. The composition may comprise a pretreatment composition,
a detersive composition, a rinse agent composition or a combination
thereof. The composition includes water-soluble cation and a source
of alkalinity. The anionic alkaline source is selected from at
least one of hydroxide anion or carbonate anion or a combination
thereof. The cation is selected from magnesium, titanium, and
aluminum, or combinations thereof. The source of alkalinity is
provided in an amount effective to provide a use composition having
a pH of greater than about 7. The cation is present in sufficient
amount to form an in situ conversion agent. A conversion agent is a
water-insoluble hydroxide precipitate that causes calcium in hard
water to precipitate as aragonite thereby softening the water. The
insoluble hydroxide reduces the contact angle of water on hard
surfaces such as wares thus reducing water spotting. Methods for
using and manufacturing such compositions are provided.
Inventors: |
Smith; Kim R.; (Woodbury,
MN) ; Olson; Keith E.; (Apple Valley, MN) ;
Monsrud; Lee J.; (Inver Grove Heights, MN) ; Mills;
Kristen A.; (Hopkins, MN) ; Rischmiller; Michael;
(Faribault, MN) |
Correspondence
Address: |
ECOLAB INC.
MAIL STOP ESC-F7, 655 LONE OAK DRIVE
EAGAN
MN
55121
US
|
Assignee: |
ECOLAB INC.
St. Paul
MN
|
Family ID: |
39939966 |
Appl. No.: |
12/114355 |
Filed: |
May 2, 2008 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60927575 |
May 4, 2007 |
|
|
|
Current U.S.
Class: |
510/225 ;
510/220 |
Current CPC
Class: |
C23G 1/22 20130101; C11D
3/046 20130101; C11D 11/0023 20130101; C02F 5/02 20130101; C23F
11/18 20130101; C23G 1/20 20130101; C11D 3/10 20130101; C11D 7/10
20130101; C23F 11/08 20130101; C02F 2303/22 20130101; C23F 11/124
20130101; C02F 5/06 20130101; C02F 2303/14 20130101; C11D 3/044
20130101 |
Class at
Publication: |
510/225 ;
510/220 |
International
Class: |
C11D 3/04 20060101
C11D003/04; C11D 17/00 20060101 C11D017/00 |
Claims
1. A composition useful in treating hard surfaces, comprising: a
substantially sequestrant-free source of at least one water-soluble
cation selected from magnesium, titanium, and aluminum; and a
source of alkalinity including at least one hydroxide anion
compound such that the cation and anion react to form a
water-insoluble hydroxide precipitate that constitutes a conversion
agent thereby softening the water.
2. A composition according to claim 1, wherein water-insoluble
oxide precipitate is comprised of nanoparticles having an average
particulate size of less than about 500 nanometers.
3. A composition according to claim 1, wherein the conversion agent
causes calcium carbonate in hard water to precipitate as
aragonite.
4. A composition according to claim 1, wherein the cation
concentration is comprised of between about 10 ppm and about 1000
ppm.
5. A composition according to claim 1, wherein the composition is
provided in solid form.
6. A composition according to claim 1, wherein the composition is
substantially phosphate or phosphorous free.
7. A warewashing composition comprising: (a) a substantially
sequestrant-free source of between about 10 and 800 ppm of at least
one water-soluble cation selected from magnesium, titanium, and
aluminum,; and (b) a source of alkalinity including at least one
hydroxide anion compound such that the cation and anion react to
form a conversion agent thereby softening the water.
8. The composition of claim 7, wherein the combination of the
cation and the source of alkalinity causes a decrease in the
contact angle of water on the surface of the wares to reduce
spotting.
9. The composition according to claim 7, wherein a ware washed with
the composition has a contact angle of water of less than 25
degrees.
10. The composition according to claim 7, wherein the conversion
agent is comprised of water insoluble hydroxide precipitate causing
calcium carbonate in hard water to precipitate as aragonite
11. The composition according to claim 7, wherein a ware treated
with the composition has a contact angle of water of less than 20
degrees.
12. The composition according to claim 7, wherein the composition
is a warewashing detergent further comprising about 0.5 wt. % to
about 15 wt. % stabilizers.
13. The composition according to claim 7, wherein the composition
further comprises about 0.5 wt. % and about 15 wt. %
dispersant.
14. The composition according to claim 7, wherein the composition
comprises about 5 wt. % to about 60 wt. % water.
15. The composition according to claim 7, wherein the composition
comprises about 2 wt. % to about 8 wt. % water.
16. The composition according to claim 8, wherein the composition
comprises a block having a size of at least about 5 grams.
17. The composition according to claim 7, further comprising a
water-soluble packaging material enclosing the composition.
18. The composition according to claim 17, wherein the
water-soluble packaging material comprises polyvinyl alcohol.
19. The composition according to claim 16, wherein the composition
is provided within the water-soluble packaging material in an
amount sufficient to provide a unit dose for application in a
dishwashing machine.
20. The composition according to claim 7 wherein the composition
comprises a rinse agent.
21. A composition according to claim 7, wherein the composition
comprises is substantially phosphorous or phosphate free.
22. A method for using a warewashing composition, the method
comprising: (a) diluting the composition with water at a dilution
ratio of water to composition of at least about 200:1, wherein the
composition comprises: (i) a substantially sequestrant-free source
of at least one water-soluble cation selected from magnesium,
titanium and aluminum; and (ii) a source of alkalinity selected
from at least one of hydroxide anion or carbonate anion such that
the cation and anion react to form a conversion agent resulting in
softened water; and (b) washing ware with the use composition in an
automatic dishwashing machine.
23. A method according to claim 22, wherein the use composition
comprises a total of free cation concentration of greater than
about 200 ppm.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority to U.S. Provisional
Application Ser. No. 60/927,575 filed on May 4, 2007 and entitled
"Compositions Containing Magnesium Salt and Methods of Using", the
disclosure of which is incorporated herein by reference.
[0002] This application is also related to: U.S. patent application
Ser. No. ______, entitled "Cleaning Compositions with Water
Insoluble Conversion Agents and Methods of Making and Using Them"
(Attorney Docket No. 2454USU1); U.S. patent application Ser. No.
______, entitled, "Water Soluble Magnesium Compounds as Cleaning
Agents and Methods of Using Them" (Attorney Docket No. 2372USU1);
U.S. patent application Ser. No. ______, entitled "Water Treatment
System and Downstream Cleaning Methods" (Attorney Docket No.
2428USU1); U.S. patent application Ser. No. ______, entitled
"Cleaning Compositions Containing Water Soluble Magnesium Compounds
and Methods of Using Them" (Attorney Docket No. 2488USU1); U.S.
patent application Ser. No. ______, entitled "MG++ Chemistry and
Method for Fouling Inhibition in Heat Processing of Liquid Foods
and Industrial Processes" (Attorney Docket No. 2400USU1); U.S.
patent application Ser. No. ______, entitled "Compositions
Including Hardness Ion and Gluconate and Methods Employing Them to
Reduce Corrosion and Etch" (Attorney Docket No. 163.2365USU1); U.S.
patent application Ser. No. ______, entitled "Compositions
Including Hardness Ion and Silicate and Methods Employing Them to
Reduce Corrosion and Etch" (Attorney Docket No. 163.2487USU1); U.S.
patent application Ser. No. ______, entitled "Compositions
Including Hardness Ion and Threshold Agent and Methods Employing
Them to Reduce Corrosion and Etch" (Attorney Docket No.
163.2406USU1); and U.S. patent application Ser. No. ______,
entitled "Warewashing Compositions for Use in Automatic Dishwashing
Machines and Method for Using" (Attorney Docket No. 2378USU1), all
commonly assigned to Ecolab, Inc., are filed on the same date as
this application being May 2, 2008 and are all incorporated herein
by reference for all purposes.
FIELD OF THE INVENTION
[0003] The invention relates to compositions useful in automatic
warewashing, methods and articles of manufacture comprising in situ
generation of a magnesium hydroxide in a detergent or rinse agent
composition to impart surface modifying benefits for all types of
hard surfaces.
[0004] The use of the composition of the invention allows for the
creation of water-insoluble hydroxide in situ providing benefits
that include at least one of the following improved surface
properties: wetting and sheeting, uniform drying, anti-spotting,
anti-staining, anti-filming, and self cleaning relative to dishware
surfaces unmodified with such systems. In situ generation of
water-insoluble hydroxide overcomes the many drawbacks associated
with incorporating preexisting magnesium hydroxide or nanoparticles
into a product. Compositions of the invention are useful in
automatic dishwashing machines including commercial and/or domestic
dishwashing machines. Compositions of the invention are also useful
in hard surface cleaning such as shower stalls and automotive
cleaning to name a couple.
BACKGROUND OF THE INVENTION
[0005] Hard surfaces that are washed but not dried often suffer
from spotting. In particular, glassware, dishes, and cutlery washed
in an automatic dishwasher may develop hard water spots. Such hard
water spots are undesirable because they have an undesirable
appearance causing the clean objects to appear dirty. To overcome
this problem, rinse aids are often used to minimize or hopefully
eliminate such spotting.
[0006] Some commercially available rinse aids include
nanoparticles. Adding nanoparticles to rinse aids provide desirable
results in improving sheeting, thus reducing hard water spots.
However, incorporating nanoparticles into rinse aids has its
drawbacks. While the benefits of including nanoparticles are
impressive, the drawbacks may outweigh the advantages.
Incorporating nanoparticles into a detergent or rinse aid is
expensive. Nanoparticles may be purchased commercially from
vendors, but in the detergent and rinse aid market, it is often a
prohibitively expensive ingredient. While nanoparticles are sold
commercially, their availability is largely limited because many
vendors do not sell them nor do many manufacturers manufacture
them. Additionally, nanoparticles can be difficult and dangerous to
handle. They pose a potential hazard to workers who risk aspirating
the minute particles into their respiratory system resulting in
serious health problems. Another drawback is that the nanoparticles
often clump or agglomerate thus reducing or eliminating their
effectiveness. Agglomeration results in particles that are not
present in the form of discrete particles, but instead
predominantly assume the form of agglomerates due to consolidation
of the primary particles. Such agglomerates may reach diameters of
several thousand nanometers, such that the desired characteristics
associated with the nanoscale nature of the particles cannot be
achieved. If agglomeration occurs, an expensive, dangerous to
handle ingredient loses its ability to improve sheeting and reduce
hard water spots.
[0007] Alternatively, one may add magnesium hydroxide to a
detergent to attempt to control hard water scale through the
precipitation of calcium carbonate in a nonscaling crystalline form
believed to be aragonite. However, the commercially available forms
of magnesium hydroxide are a very fine powder, an aqueous slurry,
or very large granules; all of which present problems in bulk
handling in a plant. It is apparent that there is a continuing need
to improve the various properties of all dishware surfaces in
automatic dishwashers, including but not limited to glass,
plastics, mirrors, metals, and ceramic surfaces. Such improvement
would result in dishware surfaces having one or more of the
following highly desirable modified surface properties such as
improved wetting and sheeting, uniform drying, anti-spotting,
anti-staining, anti-filming, and durability. Desirably, such
improvement would provide the benefits of including nanoparticles
or magnesium hydroxide into the composition yet would exclude all
of the drawbacks associated with inclusion of such ingredients in
the composition.
SUMMARY OF THE INVENTION
[0008] A warewashing composition is provided according to the
invention. A composition useful in automatic warewashing is
provided comprising a substantially sequestrant-free water-soluble
source of at least one cation selected from magnesium, titanium, or
aluminum, and a source of alkalinity selected from at least one
hydroxide anion such that the cation and anion react causing in
situ formation of a water-insoluble hydroxide thereby causing
calcium in hard water to precipitate in a non-hard water scaling
form believed to be aragonite. Without being bound by theory, it is
believed that water-insoluble hydroxide precipitate that forms are
particles. In an embodiment of the invention, these particles are
nanoparticles. In the environment of an automatic warewashing
machine due to agitation, the precipitate/particles actually are
nanoparticles having an average particulate size of less than about
500 nanometers. However, we have found that even when the particles
exceed 500 nanometers, they are effective in reducing water
spotting and the like.
[0009] The aragonite crystals are exceedingly fragile crystals that
do not readily adhere to hard surfaces. This is compared to calcite
crystals that are very sturdy cubic formations and readily adhere
and bind to hard surfaces. Without being bound by theory, it is
believed that forcing calcium to precipitate as aragonite minimizes
the likelihood that calcium carbonate crystals will grow in the
hard water scaling form of calcite. While we are uncertain whether
or not the aragonite acts as a coating on the wares thus providing
dishware surfaces having one or more of the following highly
desirable modified surface properties such as improved wetting and
sheeting, uniform drying, anti-spotting, anti-staining,
anti-filming, and durability or simply is a form of calcium
carbonate crystals with adhesion to the ware surfaces is
unimportant. From an appearance standpoint an important improvement
is reducing the untoward appearance of water spots and lime scale
formation over prolonged use. In short, it is believed that the
composition of the invention provides in situ production of
water-insoluble hydroxide particles that in turn cause aragonite
crystal formation thus providing a composition with all of the
benefits of including nanoparticles or magnesium hydroxide yet
obviating the need to purchase or handle fine powders, large
granules, or aqueous slurries of these ingredients.
[0010] In order to produce the insoluble hydroxide precipitate in
situ, a sufficient amount of the water-soluble cation must be
present. The water-soluble cation is available to react with the
hydroxide anion present in the alkaline source thus forming a
water-insoluble hydroxide. The water-insoluble hydroxide is
generated in situ and may be in the form of nanoparticulates and is
a conversion agent thus causing aragonite crystal formation and
prohibiting calcium carbonate crystal formation. The overall result
is fewer water spots on treated wares or surfaces, softened water
and no calcite formation otherwise referred to as lime scale.
[0011] One may practice the invention in any order or
simultaneously. That is, the alkaline hydroxide source may be
introduced to the wares followed by the cation or the two may be
introduced simultaneously. In one aspect of the invention, the
water-soluble cation source and the water-soluble hydroxide anion
source are incorporated into a detergent or a rinsing composition.
The water-soluble cation reacts with the alkaline hydroxide source
to form a water-insoluble hydroxide. It is undetermined whether the
hydroxide precipitate acts to coat the wares or merely acts to
prevent calcite from forming and coating the wares. The overall
result is that the hydroxide precipitate acts to improve the
wetting characteristics of the ware surfaces resulting in reduced
water spots. One feature of the invention is that the particles or
the water-insoluble hydroxide precipitate is formed in situ as
compared to adding the hydroxide precipitate to a concentrated
composition or to a use composition.
[0012] A method for using the composition is provided according to
the invention. The method can include steps of diluting a
composition with water at a dilution ratio of water to concentrate
(whether the concentrate is a detergent composition or a rinse
agent composition) of at least about 20:1, and washing ware with
the use composition in an automatic dishwashing machine. The method
can include steps of diluting a concentrate composition with water
to achieve a use composition having at least about 500 to 5000 ppm
total detergent, and treating ware with the use composition in an
automatic dishwashing machine. The term "ware" includes items such
as eating and cooking utensils. As used herein, the term
"warewashing" refers to washing, cleaning, or rinsing ware.
[0013] A method for using a composition is provided according to
the invention. The method can include steps of diluting a
concentrated composition with water at a dilution ratio of water to
concentrated composition of at least about 20:1 and washing or
rinsing a hard surface with the use composition. The method can
include steps of diluting a concentrate composition with water to
achieve a use composition having at least about 500 to 20000 ppm
total detergent, and washing or rinsing a hard surface with the use
composition. Exemplary "hard surfaces" that can be washed or rinsed
using a composition of the invention include showers, sinks,
toilets, bathtubs, countertops, windows, mirrors, transportation
vehicles, floors, and the like.
[0014] An advantage of the invention is that it is substantially
free of hard water ion chelating agents or sequestrants otherwise
necessary in such warewashing or hard-surface cleaning
compositions. Chelating agents or sequestrants are expensive
ingredients that are largely biologically unfriendly components. It
is an advantage of the present invention that the benefits of
reduced water spotting and the like are observed even without the
incorporation of chelants or sequestrants. Such chelants or
sequestrants are commonly referred to as "builders" in the art.
DETAILED DESCRIPTION OF THE INVENTION
[0015] The invention provides a composition for protecting articles
such as glassware from water spots in an automatic dishwashing or
warewashing machine during automatic dishwashing or warewashing or
during hard surface treatment. The invention provides improved
washed dishware surfaces having one or more of the following highly
desirable modified surface properties such as improved wetting and
sheeting, uniform drying, anti-spotting, anti-staining,
anti-filming, and durability.
[0016] According to the invention, a water-soluble source of at
least one cation is selected from magnesium, aluminum, or titanium.
In a preferred embodiment, the composition is substantially builder
or sequestrant free.
[0017] The term "builder" as used herein refers to components of
the composition that bind with ions that cause hard water. One
skilled in the art will recognize that hardness in water usually
consists of calcium (Ca.sup.2+), magnesium (Mg.sup.2+) ions and
possibly other dissolved compounds such as bicarbonates and
sulfates. Although water hardness usually only measures the total
concentrations of calcium and magnesium (the two most prevalent,
divalent metal ions), iron, aluminum, and manganese may also be
present at elevated ppm levels in some geographical locations. In
the case of automatic warewashing machines, the ions causing hard
water may be present from the incoming wash water, the soil, or
from the substrates being washed. "Builders" as used herein bind
with water hardness ions in a specific molar ratio to form
water-soluble or insoluble compounds. Some examples of builders
that form insoluble compounds include sodium triphosphate (STP) and
zeolite A. Some examples of builders forming soluble compounds
include sodium tripolyphosphate (STPP), ethylenediaminetetraacetic
acid (EDTA), diethylene triamine pentaacetic acid (DTPA),
nitrilotriacetate (NTA), and citrate to name a few.
[0018] As used herein, the terms "chelating agent" and
"sequestrant" do not include compounds that soften water by
precipitating water hardness ions as the scale-forming calcium or
magnesium salts of bicarbonate, carbonate, hydroxide, or silicate
anion, i.e. precipitating water hardness ions as water hardness
scale. Some materials that aren't chelating agents or sequestrants
can also reduce water hardness by precipitating water hardness ions
as the scale-forming calcium or magnesium salts of bicarbonate,
carbonate, hydroxide, or silicate anion. Such formation of hard
water scale is undesirable and leads to hard water spotting during
the warewashing process.
[0019] As used herein, the term "free of chelating agent" or
"substantially sequestrant free" refers to a composition, mixture,
or ingredients that does not contain a chelating agent or
sequestrant or to which a chelating agent or sequestrant has not
been added. Should a chelating agent or sequestrant be present
through contamination of a composition, mixture, or ingredient that
is free of chelating agent, the amount of a chelating agent or
sequestrant shall be less than 5.0 wt-%. In an embodiment, such an
amount of a chelating agent or sequestrant shall be less than 2.0
wt-%. In an embodiment, such an amount of a chelating agent or
sequestrant is less then 0.5 wt-%. In an embodiment, such an amount
of a chelating agent or sequestrant is less than 0.1 wt-%.
[0020] As used herein, the term "lacking an effective amount of
builder" refers to a composition, mixture, or ingredients that
contains too little chelating agent, builder, threshold agent or
sequestrant to measurably affect the hardness of water.
[0021] The term "builder-free" as used herein refers to a
composition that is substantially free of those compounds that
chelate or sequester calcium or form insoluble compounds when
binding with any of the cations of the invention. The cations
useful in the composition of the invention include magnesium,
calcium, molybdenum, titanium, iron, and zinc.
[0022] The term "water-soluble" as used herein refers to a compound
that can be dissolved in water at a concentration of more than 1 wt
%.
[0023] The term "water-insoluble" as used herein refers to a
compound that can be dissolved in water only to a concentration of
less than 0.1 wt %.
[0024] As used herein, the terms "sparingly soluble" or "sparingly
water soluble" refer to a compound that can be dissolved in water
only to a concentration of 0.1 to 1.0 wt %.
[0025] As used herein, the term "conversion agent" refers to a
species that causes solubilized calcium in water to precipitate
from solution as calcium carbonate in a form that is believed to be
the thermodynamically unfavorable crystal form aragonite rather
than as the thermodynamically favorable crystal form calcite.
Aragonite is a fragile crystal which doesn't bind well to surfaces
and doesn't form hard water scale while calcite is a more robust
crystal which binds tightly to surfaces, forming a hard water scale
that's not seen with aragonite.
[0026] The term, "threshold agent" as used herein refers to a
compound that inhibits crystallization of water hardness ions from
solution, but that need not form a specific complex with the water
hardness ion. This distinguishes a threshold agent from a chelating
agent or sequestrant. Threshold agents include a polyacrylate, a
polymethacrylate, an olefin/maleic copolymer, and the like.
[0027] As used herein, the terms "residue" or "coating" include
substantially covering a surface, or portion thereof, as well as
only partially covering a surface, such as those residues or
coatings that after drying leave gaps in coverage on a surface.
When it is said that the particles leave a residue or coating as
described herein, it is understood that the residues or coatings
need not cover the entire surface. For instance, the particles or
coatings are considered applied to a surface even if they modify a
portion of the surface.
[0028] As used herein, the term "antiredeposition agent" refers to
a compound that helps keep suspended in water instead of
redepositing onto the object being cleaned.
[0029] As used herein, the term "phosphate-free" refers to a
composition, mixture, or ingredients that does not contain a
phosphate or phosphate-containing compound or to which a phosphate
or phosphate-containing compound has not been added. Should a
phosphate or phosphate-containing compound be present through
contamination of a phosphate-free composition, mixture, or
ingredients, the amount of phosphate shall be less than 0.5 wt %.
In an embodiment, the amount of phosphate is less then 0.1 wt-%. In
an embodiment, the amount of phosphate is less than 0.01 wt %.
[0030] As used herein, the term "phosphorus-free" refers to a
composition, mixture, or ingredients that do not contain phosphorus
or a phosphorus-containing compound or to which phosphorus or a
phosphorus-containing compound has not been added. Should
phosphorus or a phosphorus-containing compound be present through
contamination of a phosphorus-free composition, mixture, or
ingredients, the amount of phosphorus shall be less than 0.5 wt %.
In an embodiment, the amount of phosphorus is less than 0.1 wt-%.
In an embodiment, the amount of phosphorus is less than 0.01 wt
%.
[0031] The term "functional material" or "functional additives"
refers to an active compound or material that affords desirable
properties to the solid or dissolved composition. For example, the
functional material can afford desirable properties to the solid
composition such as enhancing solidification characteristics or
dilution rate. The functional material can also, when dissolved or
dispersed in an aqueous phase, provide a beneficial property to the
aqueous material when used. Examples of optional functional
materials include surfactant, cleaning agent, softening agent,
buffer, anti-corrosion agent, bleach activators secondary hardening
agent or solubility modifier, detergent filler, defoamer,
anti-redeposition agent, antimicrobials, rinse aid compositions, a
threshold agent or system, aesthetic enhancing agent (i.e., dye,
perfume), lubricant compositions, additional bleaching agents,
functional salts, hardening agents, solubility modifiers, enzymes,
other such additives or functional ingredients, and the like, and
mixtures thereof. Functional materials added to a composition will
vary according to the type of composition being manufactured, and
the intended end use of the composition. "Cleaning," means to
perform or aid in soil removal, bleaching, microbial population
reduction, or combination thereof.
[0032] As used herein, a solid cleaning composition refers to a
cleaning composition in the form of a solid such as a powder, a
flake, a granule, a pellet, a tablet, a lozenge, a puck, a
briquette, a brick, a solid block, a unit dose, or another solid
form known to those of skill in the art. The term "solid" refers to
the state of the detergent composition under the expected
conditions of storage and use of the solid detergent composition.
In general, it is expected that the detergent composition will
remain in solid form when exposed to temperatures of up to about
100.degree. F. and greater than about 120.degree. F.
[0033] The term "solid" also is used to describe the processed
composition, it is meant that the hardened composition will
substantially retain its shape under moderate stress or pressure or
mere gravity, as for example, the shape of a mold when removed from
the mold, the shape of an article as formed upon extrusion from an
extruder, and the like. The degree of hardness of the solid cast
composition can range from that of a fused solid block that is
relatively dense and hard, for example, like concrete, to a
consistency characterized as being malleable and sponge-like,
similar to caulking material.
[0034] As used herein, weight percent (wt-%), percent by weight, %
by weight, and the like are synonyms that refer to the
concentration of a substance as the weight of that substance
divided by the total weight of the composition and multiplied by
100.
[0035] As used herein, the term "about" modifying the quantity of
an ingredient in the compositions of the invention or employed in
the methods of the invention refers to variation in the numerical
quantity that can occur, for example, through typical measuring and
liquid handling procedures used for making concentrates or use
solutions in the real world; through inadvertent error in these
procedures; through differences in the manufacture, source, or
purity of the ingredients employed to make the compositions or
carry out the methods; and the like. The term about also
encompasses amounts that differ due to different equilibrium
conditions for a composition resulting from a particular initial
mixture. Whether or not modified by the term "about", the claims
include equivalents to the quantities.
[0036] The term "in situ" as used herein refers to creation of an
element, or in the case of the invention, creation of a
water-insoluble hydroxide precipitate either upon formation of a
use composition, or upon delivery of the use composition to the
treatment surface, or when forming the concentrate composition of
the invention. "In situ" formation does not include compositions or
concentrates wherein the water-insoluble hydroxide is in existence
before creation of the concentrate. That is, "in situ" would not
include concentrate compositions or use compositions in which
water-insoluble magnesium hydroxide is added as a pre-existing
ingredient.
Cation Source
[0037] The composition of the invention includes a source of a
water-soluble cation selected from at least one water-soluble
cation of magnesium, aluminum, or titanium. The cationic source
also refers to the possibility that any combination of cations is
provided. The cation is provided in sufficient amount to react with
the source of alkalinity to form a cation hydroxide compound that
causes calcium carbonate to precipitate as aragonite instead of
calcite. One method of providing sufficient cation is to leave a
residue on the wares. The amount of cation provided in the
composition is preferably sufficient to react with the anionic
source of alkalinity as hydroxide anion to form a conversion
agent.
[0038] Preferably, the water-soluble source of the cations provided
in the composition of the invention are comprised of water-soluble
salts of magnesium, titanium, iron, and aluminum. The composition
of the cations is important, as the cations should be soluble in
water, particularly during the particular phase of the ware washing
in which they are employed. Once contacted with the anions from the
alkaline source, the cations form an insoluble hydroxide
precipitate.
[0039] The cationic source preferably remains in solution until the
anionic alkaline source contacts the cations. In an alternate
embodiment, the insoluble hydroxide precipitate may form before
contacting the wares. This will occur when the cationic source and
the alkaline anions come into contact in the event of a
pretreatment step or in the detergent concentrate itself.
[0040] It should be understood that magnesium cation, titanium
cation, aluminum cation, and zinc cation can be considered a source
of magnesium cation, titanium cation, aluminum cation, and zinc
cation. The source of cation can be provided as organic salts,
inorganic salts, and mixtures thereof. Exemplary sources of
magnesium cation include magnesium salts such as magnesium acetate,
magnesium chloride, magnesium sulfate, and mixtures thereof. An
exemplary source of titanium cation ion includes titanium chloride.
Exemplary sources of aluminum cation include aluminum sulfate,
aluminum chloride and mixtures thereof In addition, the source of
cation can be selected as those components that are characterized
by the United States Food and Drug Administration as direct or
indirect food additives. Because the warewashing detergent
composition will be used to wash articles that contact food, it may
be desirable to select the source of cation as components that are
characterized by the United States Food and Drug Administration as
direct or indirect food additives. By way of theory, it is believed
that the source of cation that deposit onto the surfaces of
articles that are being washed. In addition, it is believed that
the alkaline source of anions causes the cations to precipitate.
The precipitate remains on the article to improve wetting,
sheeting, uniform drying, anti-spotting, anti-staining,
anti-filming, and reduces the untoward appearance of water
spots
[0041] It is expected that the cationic source will form a water
insoluble conversion agent when contacted with the anionic alkaline
source. Without being bound by theory it is believed that the water
insoluble hydroxide, also referred to as a conversion agent may
also be referred to herein as particles. As a result, the
conversion agent causes calcium carbonate present in the water to
precipitate as non-scaling aragonite instead of calcite. If the
particles deposit on the surface of the wares it can be
substantially invisible to the human eye. It should be understood
that the phrase "substantially invisible to the human eye" refers
to the lack of visible filming by the particles. Visible filming
refers to a cloudy appearance that may begin with an iridescent
film that displays rainbow hues in light reflected from the glass.
It is expected that the precipitate that forms on the glass
provides a film on the glass that is both substantially invisible
to the human eye and that provides a functional layer. By
functional layer it is meant that particles provide modified
surface properties on the wares such as improved wetting and
sheeting, uniform drying, anti-spotting, anti-staining,
anti-filming, and durability.
Anionic Source of Alkalinity
[0042] A source of alkalinity is provided in the composition of the
invention as a hydroxide anion.
[0043] As used herein, the term "alkaline" refers to those
compositions having a pH above 7, preferably a pH of above about 8,
and more preferably a pH above about 9.
[0044] The alkaline source of the anions has a pH high enough to
cause the cations present to form an oxide precipitate whether the
cations are present in the automatic warewashing machine, in the
feedwater or precursor to the detersive cycle, or in the wash
water, or in the rinse water. Such a pH is above about 7,
preferably above about 8, and more preferably above about 9. One
skilled in the art will recognize that the amount of anions
necessary will in part depend upon the pH of the alkaline
source.
[0045] According to the invention, an alkaline source is a
hydroxide anion such that the cation and anion react to form a
water-insoluble conversion agent. The anionic alkaline source of
the invention preferably has a pKa of greater than about 8, more
preferably the alkaline source of the invention comprises a pKa of
greater than about 9, and most preferably the alkaline source of
the invention comprises a pKa of greater than about 10. Additional
alkaline agents such as, for example, alkali metal carbonates,
alkanolamines, alkali metal silicates and the like may also be
present in the composition for other purposes than forming a
water-insoluble conversion agent.
[0046] As previously mentioned with respect to the detersive
agents, the alkaline component(s) of the invention are best
selected from those components characterized by the United States
Food and Drug Administration as direct or indirect food additives.
When the composition of the invention is used to wash articles that
contact food, it is desirable to select the source of alkalinity as
components that are characterized by the United States Food and
Drug Administration as direct or indirect food additives.
[0047] The alkaline source of the composition may be organic or
inorganic. Examples of organic bases useful in the present
invention include but are not limited to triethanolamine, dodecyldi
(hydroxyethyl)amine, diethanolamine, tributylamine, ethoxylated
tetradecylamine or mixtures thereof. Examples of inorganic bases
useful in the composition of the present invention include but are
not limited to sodium hydroxide, potassium hydroxide, lithium
hydroxide, cesium hydroxide, sodium carbonate, potassium carbonate,
lithium carbonate, sodium silicate, potassium silicate, lithium
silicate, or mixtures thereof. One skilled in the art will also
recognize inorganic and organic bases may be combined to form the
alkaline source of the anion of the invention.
[0048] It is hypothesized that the water-insoluble hydroxide
precipitate that is formed is in part on the surface of the wares.
The hydroxide precipitate is preferably a fine precipitate that is
undetected by the naked eye. Such particles have novel and useful
properties due to the small dimensions of the particulates. As
previously mentioned, in an embodiment the particles are
nanoparticles. The term nanoparticles as used herein are particles
with diameters of about 500 nm or less. Particle size distributions
of the nanoparticles in the present invention may fall anywhere
within the range from about 1 nm, or less, to less than about 500
nm, alternatively from about 1 nm to less than about 100 nm, and
alternatively from about 1 nm to less than about 50 nm.
Alternatively, nanoparticles can also include crystalline or
amorphous particles with a particle size from about 1, or less, to
about 100 nanometers, alternatively from about 1 to about 50
nanometers. In another embodiment, the particles may be a
combination of nanoparticles and particles larger than 500 nm. In
yet another embodiment of the invention, substantially all of the
particles are greater than 500 nm. The in situ created insoluble
oxide precipitate can include particles ranging from 1 nm up to
about 5,000 nm. The benefits of the invention are experienced
regardless of the resultant particle size.
[0049] One theory is that use of the composition of the invention
would serve to create the insoluble hydroxide precipitate to create
a layer on glassware in particular to help inhibit the etched
appearance commonly found when glass is repeatedly washed in an
automatic dishwasher. Without being bound by theory, it is likely
that the insoluble hydroxide particulates, also referred to herein
as the in situ created particles, create a sacrificial layer on the
glassware prohibiting or reducing leaching of the silicon in the
glass. Practicing the invention could therefore prolong the clarity
of glass routinely washed in automatic dishwashing machines.
[0050] Yet another theory is one advanced previously. That theory
relies upon the nature of the crystals of the precipitate. In a
preferred embodiment of the invention, the insoluble oxide
precipitate serves to cause calcium carbonate in the water to
crystallize as non-scale forming aragonite crystals rather than as
the scale-forming calcite. Aragonite crystals are fragile as
compared to the sturdier carbonate crystals. Formation of aragonite
crystals prohibits or greatly diminishes the formation of calcite
scale thereby eliminating the chance that calcium carbonate
crystals can deposit upon the wares. It is a widely held belief
that calcium carbonate as its calcite crystalline form is a major
source of lime scale deposits on wares and a source of the hazy
appearance of wares.
[0051] The composition of the invention can be referred to as a
cleaning composition, a rinse composition, or a pre-treat
composition and is desirably used in automatic warewashing machines
but can be available for cleaning in environments other than inside
an automatic dishwashing or warewashing machine. It should be
understood that the term "warewashing" refers to and is meant to
include both warewashing and dishwashing. Furthermore, the
warewashing composition can refer to a concentrate and to a use
composition. In general, a concentrate is the composition that is
diluted with water to provide the use composition that contacts the
ware surfaces to provide the desired effect, such as, cleaning.
[0052] One skilled in the art will appreciate that the composition
of the invention may be provided in different embodiments. In a
first embodiment, the source of water-soluble cation may be
provided in a stand-alone detergent that may be provided in solid
or liquid form. The alkaline anion component may then also be
provided in a stand-alone format and may be provided in solid or
liquid form. In this embodiment, either component may be used as
the first treatment. Alternatively, the stand-alone components of
this embodiment may simultaneously treat the wares by themselves or
as part of a detergent.
[0053] In a second embodiment the water-soluble cation component
and the alkaline source of anion component are provided together as
a pre-treatment or a precursor to a detersive agent. The
composition of the invention may be provided along with the
detersive agents but the combination of the invention may be
provided such that when diluted with water the components are
dispersed together. That is, the components of the invention are
more readily diluted with water than the detersive agents allowing
the components of the invention to contact the wares before the
detersive agents.
[0054] In a third embodiment the water-soluble cation component and
the alkaline source of anion component are provided together as
part of a detergent or as a rinse agent.
[0055] The composition according to the invention may include an
effective amount of one or more non-conversion agent forming
alkaline sources to maintain the composition at an alkaline pH. The
alkaline source may also enhance cleaning of a substrate and
improve soil removal performance of the composition. In general, an
effective amount of one or more alkaline sources should be
considered as an amount that provides a use composition having a pH
of at least about 8. When the use composition has a pH of between
about 8 and about 10 it can be considered mildly alkaline, and when
it has a pH of between 10 and 11 it can be considered alkaline, and
when the pH is greater than about 12 the use composition can be
considered caustic. In general, it is desirable to provide the use
composition as an alkaline cleaning composition or caustic cleaning
composition because of improved cleaning performance.
[0056] In general, it is expected that the concentrate of the
invention will include the anionic alkaline source in an amount of
at least about 5 wt. %, at least about 10 wt. %, or at least about
15 wt. %. In order to provide sufficient room for other components
in the concentrate, the anionic alkaline source can be provided in
the concentrate in an amount of less than about 60 wt. %. In
addition, the anionic alkaline source can be provided at a level of
less than about 30 wt. % and less than about 20 wt %.
[0057] The composition that contacts the articles to be washed in
an automatic dishwashing process can be referred to as the use
composition. The use composition can be provided as a detersive
agent at a solids concentration that provides a desired level of
detersive properties. The solids concentration refers to the
concentration of the non-water components in the use composition.
The warewashing composition prior to dilution to provide the use
composition can be referred to as the warewashing composition
concentrate or more simply as the concentrate. The concentrate can
be provided in various forms including as a liquid and as a solid.
In a preferred embodiment the composition of the invention is
provided in solid form. It should be understood that pastes and
gels can be considered a type of liquid. In addition, it should be
understood that powders, agglomerates, pellets, tablets, and blocks
are types of a solid.
[0058] It is expected that the composition of the invention will be
used by diluting the concentrate with water at the site or location
of use to provide the use composition. In many cases when using the
composition of the invention in an automatic dishwashing or
warewashing machine, it is expected that the site or location of
use will be inside the automatic dishwashing or warewashing
machine. Although the location of use will generally be at or
inside an automatic dishwashing machine, whether or not the cation
source and alkaline anion source of the invention are combined will
depend upon the particular embodiment of the invention used. That
is, if the components of the invention are stand-alone components,
then the composition is used in a residential or home-style
dishwashing machine, it is expected that the alkaline source may be
placed in the detergent compartment along with the cation source.
Alternatively, both may be placed in the rinse aid compartment of
the dishwashing machine. Often these detergent compartments and
rinse aid compartments are located in the door of the dishwashing
machine on top of machine or in close proximity to the machine. The
cation and alkaline source may be provided in the form that allows
for introduction of a single dose of the composition into the
appropriate compartment. In general, single dose refers to the
amount of the cation or source of alkalinity that is desired for a
single warewashing application. In many commercial dishwashing or
warewashing machines, and even for certain residential dishwashing
machines, it is expected that a large quantity of concentrate can
be provided in a compartment that allows for the release of a
single dose amount of the composition for each warewashing or
dishwashing cycle. Such a compartment may be provided as part of
the warewashing or dishwashing machine or it may be provided as a
separate structure connected to the warewashing or dishwashing
machine by a hose for delivery of liquid thereto. For example, a
block of the concentrate can be provided in a hopper, and water can
be sprayed against the surface of the block to provide a liquid
concentrate that can be introduced into the dishwashing machine.
The hopper can be a part of the dishwashing machine or it can be
provided separate from the dishwashing machine.
[0059] The use composition of the invention can have a solids
content that is sufficient to provide the desired level of cleaning
while avoiding wasting the use composition by using too much. In
general, it is expected that the use composition will have a solids
content of at least about 0.05 wt. %, and can have a solids content
of between about 0.05 wt. % and about 0.75 wt. %. The use
composition can be prepared from the concentrate by diluting with
water at a dilution ratio that provides convenient use of the
concentrate and provides the formation of a use composition having
desired detersive properties. It is expected that the concentrate
can be diluted at a ratio of water to concentrate of at least about
20:1, and can be at between about 20:1 and about 200:1, and can be
between about 20:1 and about 2000:1 to provide a use composition
having desired properties.
[0060] The warewashing composition can be provided in the form of a
solid. Exemplary solid dishwashing compositions and methods of
manufacturing such solid compositions are disclosed in U.S. Pat.
Nos. 6,410,495 to Lentsch et al., 6,369,021 to Man et al.,
6,258,765 to Wei et al, 6,177,392 to Lentsch et al., 6,164,296 to
Lentsch et al., 6,156,715 to Lentsch et al., and 6,150,324 to
Lentsch et al. The compositions and methods of manufacturing of
each of these patents are incorporated herein by reference for all
purposes.
Cleaning Agent
[0061] The composition of the invention can optionally include at
least one cleaning agent comprising a surfactant or surfactant
system. A variety of surfactants can be used in a warewashing
composition, such as additional nonionic, anionic, cationic, and
zwitterionic surfactants. It should be understood that surfactants
are an optional component of the warewashing composition and can be
excluded from the concentrate. The warewashing detergent
composition, when provided as a concentrate, can include the
cleaning agent in a range of between about 0.5 wt. % and about 20
wt. %, between about 0.5 wt. % and about 15 wt. %, between about
1.5 wt. % and about 15 wt. %, between about 1 wt. % and about 10
wt. %, and between about 2 wt. % and about 5 wt. %. Additional
exemplary ranges of surfactant in a concentrate include about 0.5
wt. % to about 5 wt. %, and about 1 wt. % to about 3 wt. %.
[0062] Exemplary surfactants that can be used are commercially
available from a number of sources. For a discussion of
surfactants, see Kirk-Othmer, Encyclopedia of Chemical Technology,
Third Edition, volume 8, pages 900-912 incorporated herein for all
purposes. When the composition of the invention includes a cleaning
agent, the cleaning agent can be provided in an amount effective to
provide a desired level of cleaning.
[0063] Anionic surfactants useful in the composition of the
invention (whether it is a detersive composition, or a pretreatment
composition, or a rinse agent composition) includes, for example,
carboxylates such as alkylcarboxylates (carboxylic acid salts) and
polyalkoxycarboxylates, alcohol ethoxylate carboxylates,
nonylphenol ethoxylate carboxylates, and the like; sulfonates such
as alkylsulfonates, alkylbenzenesulfonates, alkylarylsulfonates,
sulfonated fatty acid esters, and the like; sulfates such as
sulfated alcohols, sulfated alcohol ethoxylates, sulfated
alkylphenols, alkylsulfates, sulfosuccinates, alkylether sulfates,
and the like; and phosphate esters such as alkylphosphate esters,
and the like. Exemplary anionic surfactants include sodium
alkylarylsulfonate, alpha-olefinsulfonate, and fatty alcohol
sulfates.
[0064] Nonionic surfactants useful in the composition of the
invention include, for example, those having a polyalkylene oxide
polymer as a portion of the surfactant molecule. Such nonionic
surfactants include, for example, chlorine-, benzyl-, methyl-,
ethyl-, propyl-, butyl- and other like alkyl-capped polyethylene
glycol ethers of fatty alcohols; polyalkylene oxide free nonionics
such as alkyl polyglycosides; sorbitan and sucrose esters and their
ethoxylates; alkoxylated ethylene diamine; alcohol alkoxylates such
as alcohol ethoxylate propoxylates, alcohol propoxylates, alcohol
propoxylate ethoxylate propoxylates, alcohol ethoxylate
butoxylates, and the like; nonylphenol ethoxylate, polyoxyethylene
glycol ethers and the like; carboxylic acid esters such as glycerol
esters, polyoxyethylene esters, ethoxylated and glycol esters of
fatty acids, and the like; carboxylic amides such as diethanolamine
condensates, monoalkanolamine condensates, polyoxyethylene fatty
acid amides, and the like; and polyalkylene oxide block copolymers
including an ethylene oxide/propylene oxide block copolymer such as
those commercially available under the trademarks PLURONIC.RTM. and
PLURONIC.RTM. R Series (BASF-Wyandotte), and the like; and other
like nonionic compounds. Silicone surfactants such as the ABIL.RTM.
B8852 can also be used.
[0065] Cationic surfactants that can be used in the warewashing
detergent composition or rinse agent composition include amines
such as primary, secondary and tertiary monoamines with C.sub.18
alkyl or alkenyl chains, ethoxylated alkylamines, alkoxylates of
ethylenediamine, imidazoles such as a
1-(2-hydroxyethyl)-2-imidazoline, a
2-alkyl-1-(2-hydroxyethyl)-2-imidazoline, and the like; and
quaternary ammonium salts, as for example, alkylquaternary ammonium
chloride surfactants such as
n-alkyl(C.sub.12-C.sub.8)dimethylbenzyl ammonium chloride,
n-tetradecyldimethylbenzylammonium chloride monohydrate, a
naphthylene-substituted quaternary ammonium chloride such as
dimethyl-1-naphthylmethylammonium chloride, and the like. Useful
cationic surfactants also include cationic polymers such as
diallyldimethylammonium chloride (DADMAC),
vinylbenzyldimethylammonium chloride, and the like. The cationic
surfactant can be used to provide antimicrobial properties.
[0066] Zwitterionic surfactants that can be used in the
pretreatment composition or detersive (warewashing) composition or
rinse agent composition include betaines, imidazolines, and
propinates. When the composition is intended for use as a
warewashing composition in an automatic dishwashing or warewashing
machine, the surfactants selected, if any surfactant is used, can
be those that provide an acceptable level of foaming when used
inside a dishwashing or warewashing machine. It should be
understood that warewashing compositions for use in automatic
dishwashing or warewashing machines are generally considered to be
low-foaming compositions.
[0067] The surfactant can be selected to provide low foaming
properties. One would understand that low foaming surfactants that
provide the desired level of detersive activity are advantageous in
an environment such as a dishwashing machine where the presence of
large amounts of foaming can be problematic. In addition to
selecting low foaming surfactants, one would understand that
defoaming agents could be utilized to reduce the generation of
foam. Accordingly, surfactants that are considered low foaming
surfactants as well as other surfactants can be used in the
warewashing composition and the level of foaming can be controlled
by the addition of a defoaming agent.
Other Additives
[0068] The composition of the invention can include other
additives, including conventional additives such as bleaching
agents, hardening agents or solubility modifiers, defoamers,
anti-redeposition agents, threshold agents, stabilizers,
dispersants, enzymes, aesthetic enhancing agents (i.e., dye,
perfume), and the like. Adjuvants and other additive ingredients
will vary according to the type of composition being manufactured.
It should be understood that these additives are optional and need
not be included in the cleaning composition. When they are
included, they can be included in an amount that provides for the
effectiveness of the particular type of component.
[0069] The composition of the invention generally does not include
any chelating/sequestering agents such as an aminocarboxylic acid,
a condensed phosphate, a phosphonate, or the like.
[0070] Bleaching agents for use in a cleaning compositions for
lightening or whitening a substrate, include bleaching compounds
capable of liberating an active halogen species, such as Cl.sub.2,
Br.sub.2, --OCl.sup.- and/or --OBr.sup.-, under conditions
typically encountered during the cleansing process. Suitable
bleaching agents for use in the present cleaning compositions
include, for example, chlorine-containing compounds such as a
chlorine, a hypochlorite, and chloramine. Exemplary
halogen-releasing compounds include the alkali metal
dichloroisocyanurates, chlorinated trisodium phosphate, the alkali
metal hypochlorites, monochloramine and dichloramine, and the like.
Encapsulated chlorine sources may also be used to enhance the
stability of the chlorine source in the composition (see, for
example, U.S. Pat. Nos. 4,618,914 and 4,830,773, the disclosure of
which is incorporated by reference herein for all purposes). A
bleaching agent may also be a peroxygen or active oxygen source
such as hydrogen peroxide, perborates, sodium carbonate
peroxyhydrate, phosphate peroxyhydrates, potassium permonosulfate,
and sodium perborate mono and tetrahydrate, with and without
activators such as tetraacetylethylene diamine, and the like. The
composition can include an effective amount of a bleaching agent.
When the concentrate includes a bleaching agent, it can be included
in an amount of about 0.1 wt. % to about 60 wt. %, about 1 wt. % to
about 20 wt. %, about 3 wt. % to about 8 wt. %, and about 3 wt. %
to about 6 wt. %.
[0071] The composition can include an effective amount of detergent
fillers, which does not perform as a cleaning agent per se, but
cooperates with the cleaning agent to enhance the overall cleaning
capacity of the composition. Examples of detergent fillers suitable
for use in the present cleaning compositions include sodium
sulfate, sodium chloride, starch, sugars, C.sub.1-C.sub.10 alkylene
glycols such as propylene glycol, and the like. When the
concentrate includes a detergent filler, it can be included an
amount of about 1 wt. % to about 20 wt. % and between about 3 wt. %
to about 15 wt. %.
[0072] A defoaming agent for reducing the stability of foam may
also be included in the composition to reduce foaming. When the
concentrate includes a defoaming agent, the defoaming agent can be
provided in an amount of between about 0.01 wt. % and about 3 wt.
%.
[0073] Examples of defoaming agents that can be used in the
composition includes ethylene oxide/propylene block copolymers such
as those available under the name Pluronic N3, silicone compounds
such as silica dispersed in polydimethylsiloxane,
polydimethylsiloxane, and functionalized polydimethylsiloxane such
as those available under the name Abil B9952, fatty amides,
hydrocarbon waxes, fatty acids, fatty esters, fatty alcohols, fatty
acid soaps, ethoxylates, mineral oils, polyethylene glycol esters,
alkyl phosphate esters such as monostearyl phosphate, and the like.
A discussion of defoaming agents may be found, for example, in U.S.
Pat. No. 3,048,548 to Martin et al., U.S. Pat. No. 3,334,147 to
Brunelle et al., and U.S. Pat. No. 3,442,242 to Rue et al., the
disclosures of which are incorporated by reference herein for all
purposes.
[0074] The composition can include an anti-redeposition agent for
facilitating sustained suspension of soils in a cleaning solution
and preventing the removed soils from being redeposited onto the
substrate being cleaned. Examples of suitable anti-redeposition
agents include fatty acid amides, fluorocarbon surfactants, complex
phosphate esters, styrene maleic anhydride copolymers, and
cellulosic derivatives such as hydroxyethyl cellulose,
hydroxypropyl cellulose, and the like. When the concentrate
includes an anti-redeposition agent, the anti-redeposition agent
can be included in an amount of between about 0.5 wt. % to about 10
wt. %, and between about 1 wt. % and about 5 wt. %.
[0075] Stabilizing agents that can be used include primary
aliphatic amines, betaines, borate, calcium ions, sodium citrate,
citric acid, sodium formate, glycerine, maleonic acid, organic
diacids, polyols, propylene glycol, and mixtures thereof. The
concentrate need not include a stabilizing agent, but when the
concentrate includes a stabilizing agent, it can be included in an
amount that provides the desired level of stability of the
concentrate. Exemplary ranges of the stabilizing agent include
about 0 to about 20 wt. %, about 0.5 wt. % to about 15 wt. %, and
about 2 wt. % to about 10 wt. %.
[0076] Dispersants that can be used in the composition include
maleic acid/olefin copolymers, polyacrylic acid, and its
copolymers, and mixtures thereof. The concentrate need not include
a dispersant, but when a dispersant is included it can be included
in an amount that provides the desired dispersant properties.
Exemplary ranges of the dispersant in the concentrate can be
between about 0 and about 20 wt. %, between about 0.5 wt. % and
about 15 wt. %, and between about 2 wt. % and about 9 wt. %.
[0077] Enzymes that can be included in the composition include
those enzymes that aid in the removal of starch and/or protein
stains. Exemplary types of enzymes include proteases,
alpha-amylases, and mixtures thereof. Exemplary proteases that can
be used include those derived from Bacillus licheniformix, Bacillus
lenus, Bacillus alcalophilus, and Bacillus amyloliquefacins.
Exemplary alpha-amylases include Bacillus subtilis, Bacillus
amyloliquefaceins and Bacillus licheniformis. The concentrate need
not include an enzyme. When the concentrate includes an enzyme, it
can be included in an amount that provides the desired enzymatic
activity when the warewashing composition is provided as a use
composition. Exemplary ranges of the enzyme in the concentrate
include between about 0 and about 15 wt. %, between about 0.5 wt. %
and about 10 wt. %, and between about 1 wt. % and about 5 wt.
%.
[0078] The concentrate can include water. In general, it is
expected that water may be present as a processing aid and may be
removed or become water of hydration. It is expected that water may
be present in both the liquid concentrate and in the solid
concentrate. In the case of the liquid concentrate, it is expected
that water will be present in a range of between about 5 wt. % and
about 60 wt. %, between about 10 wt. % and about 35 wt. %, and
between about 15 wt. % and about 25 wt. %. In the case of a solid
concentrate, it is expected that the water will be present in
ranges of between about 0 wt. % and about 10 wt. %, about 0.1 wt. %
and about 10 wt. %, about 1 wt. % and about 5 wt. %, and about 2
wt. % and about 3 wt. %. It should be additionally appreciated that
the water may be provided as deionized water or as softened
water.
[0079] Various dyes, odorants including perfumes, and other
aesthetic enhancing agents can be included in the composition. Dyes
may be included to alter the appearance of the composition, as for
example, Direct Blue 86 (Miles), Fastusol Blue (Mobay Chemical
Corp.), Acid Orange 7 (American Cyanamid), Basic Violet 10
(Sandoz), Acid Yellow 23 (GAF), Acid Yellow 17 (Sigma Chemical),
Sap Green (Keystone Analine and Chemical), Metanil Yellow (Keystone
Analine and Chemical), Acid Blue 9 (Hilton Davis), Sandolan
Blue/Acid Blue 182 (Sandoz), Hisol Fast Red (Capitol Color and
Chemical), Fluorescein (Capitol Color and Chemical), Acid Green 25
(Ciba-Geigy), and the like.
[0080] Fragrances or perfumes that may be included in the
compositions include, for example, terpenoids such as citronellol,
aldehydes such as amyl cinnamaldehyde, a jasmine such as
C1S-jasmine or jasmal, vanillin, and the like.
[0081] The components used to form the concentrate can include an
aqueous medium such as water as an aid in processing. It is
expected that the aqueous medium will help provide the components
with a desired viscosity for processing. In addition, it is
expected that the aqueous medium may help in the solidification
process when is desired to form the concentrate as a solid. When
the concentrate is provided as a solid, it can be provided in the
form of a block or pellet. It is expected that blocks will have a
size of at least about 5 grams, and can include a size of greater
than about 50 grams. It is expected that the concentrate will
include water in an amount of between about 1 wt. % and about 50
wt. %, and between about 2 wt. % and about 40 wt. %.
[0082] When the components that are processed to form the
concentrate are processed into a block, it is expected that the
components can be processed by extrusion techniques or casting
techniques. In general, when the components are processed by
extrusion techniques, it is believed that the composition can
include a relatively smaller amount of water as an aid for
processing compared with the casting techniques. In general, when
preparing the solid by extrusion, it is expected that the
composition can contain between about 2 wt. % and about 10 wt. %
water. When preparing the solid by casting, it is expected that the
amount of water can be provided in an amount of between about 20
wt. % and about 40 wt. %. A solid that is easily removed from a
mold or extruder or removed with minimal damage is preferred.
Forming The Concentrate
[0083] As previously mentioned, the cationic source may be formed
separate of the anionic source or the cationic source and the
anionic source may be formed together with each of these instances
alone or as part of a pretreatment composition, a detergent or
rinsing composition or any combination thereof. The following may
refer to either the formation of the cationic source, the anionic
source or a combination of both. It is noted that it may be
desirable for the cationic source and the anionic source to contact
the wares simultaneously either during a pretreatment, during the
wash cycle of an automatic warewashing machine, or during a rinse
cycle to create a conversion agent and to reduce and hopefully
eliminate the formation of calcite crystal formation in the wash
cycle. It might also be desirable that the cationic source and the
anionic source are able to react to form the conversion agent in
situ. Therefore, it might also be desirable that if the cationic
source and the anionic source are formed into a single concentrate
that either the cation or the anionic alkaline source is
encapsulated or otherwise treated to delay reaction until delivery
to the water. Such encapsulation may be achieved through the use of
water soluble polymers or similar methods. However, it is not
believed that such encapsulation is necessary. The components can
be mixed and extruded agglomerated, pressed or cast to form a solid
such as particles, pellets or blocks. Heat can be applied from an
external source to facilitate processing of the mixture.
[0084] A mixing system provides for continuous mixing of the
ingredients at high shear to form a substantially homogeneous
liquid or semi-solid mixture in which the ingredients are
distributed throughout its mass. The mixing system includes means
for mixing the ingredients to provide shear effective for
maintaining the mixture at a flowable consistency, with a viscosity
during processing of about 1,000-1,000,000 cP, preferably about
50,000-200,000 cP. The mixing system can be a continuous flow mixer
or a single or twin screw extruder apparatus.
[0085] The mixture can be processed at a temperature to maintain
the physical and chemical stability of the ingredients, such as at
ambient temperatures of about 20-80.degree. C., and about
25-55.degree. C. Although limited external heat may be applied to
the mixture, the temperature achieved by the mixture may become
elevated during processing due to friction, variances in ambient
conditions, and/or by an exothermic reaction between ingredients.
Optionally, the temperature of the mixture may be increased, for
example, at the inlets or outlets of the mixing system.
[0086] An ingredient may be in the form of a liquid or a solid such
as a dry particulate, and may be added to the mixture separately or
as part of a premix with another ingredient, as for example, the
cleaning agent, the aqueous medium, and additional ingredients such
as a second cleaning agent, a detergent adjuvant or other additive,
a secondary hardening agent, and the like. One or more premixes may
be added to the mixture.
[0087] The ingredients are mixed to form a substantially
homogeneous consistency wherein the ingredients are distributed
substantially evenly throughout the mass. The mixture can be
discharged from the mixing system through a die or other shaping
means. The profiled extrudate can be divided into useful sizes with
a controlled mass. The extruded solid can be packaged in film. The
temperature of the mixture when discharged from the mixing system
can be sufficiently low to enable the mixture to be cast or
extruded directly into a packaging system without first cooling the
mixture. The time between extrusion discharge and packaging can be
adjusted to allow the hardening of the detergent block for better
handling during further processing and packaging. The mixture at
the point of discharge can be about 20-90.degree. C., and about
25-55.degree. C. The composition can be allowed to harden to a
solid form that may range from a low density, sponge-like,
malleable, caulky consistency to a high density, fused solid,
concrete-like block.
[0088] Optionally, heating and cooling devices may be mounted
adjacent to mixing apparatus to apply or remove heat in order to
obtain a desired temperature profile in the mixer. For example, an
external source of heat may be applied to one or more barrel
sections of the mixer, such as the ingredient inlet section, the
final outlet section, and the like, to increase fluidity of the
mixture during processing. Preferably, the temperature of the
mixture during processing, including at the discharge port, is
maintained preferably at about 20-90.degree. C.
[0089] When processing of the ingredients is completed, the mixture
may be discharged from the mixer through a discharge die. The
composition eventually hardens due to the chemical reaction of the
ingredients forming a hydrate binder. The solidification process
may last from a few minutes to about six hours, depending, for
example, on the size of the cast or extruded composition, the
ingredients of the composition, the temperature of the composition,
and other like factors. Preferably, the cast or extruded
composition "sets up" or begins to hardens to a solid form within
about 1 minute to about 3 hours, preferably about 1 minute to about
2 hours, preferably about 1 minute to about 20 minutes.
[0090] The concentrate can be provided in the form of a liquid.
Various liquid forms include gels and pastes. Of course, when the
concentrate is provided in the form of a liquid, it is not
necessary to harden the composition to form a solid. In fact, it is
expected that the amount of water in the composition will be
sufficient to preclude solidification. In addition, dispersants and
other components can be incorporated into the concentrate in order
to maintain a desired distribution of components.
[0091] The packaging receptacle or container may be rigid or
flexible, and composed of any material suitable for containing the
compositions produced according to the invention, as for example
glass, metal, plastic film or sheet, cardboard, cardboard
composites, paper, and the like. Advantageously, since the
composition is processed at or near ambient temperatures, the
temperature of the processed mixture is low enough so that the
mixture may be cast or extruded directly into the container or
other packaging system without structurally damaging the material.
As a result, a wider variety of materials may be used to
manufacture the container than those used for compositions that
processed and dispensed under molten conditions. Preferred
packaging used to contain the compositions is manufactured from a
flexible, easy opening film material. Use instructions and/or
safety precautions may be attached to or printed directly on the
packaging material for the safety of the user.
[0092] The packaging material can be provided as a water-soluble
packaging material such as a water-soluble packaging film.
Exemplary water-soluble packaging films are disclosed in U.S. Pat.
Nos. 6,503,879; 6,228,825; 6,303,553; 6,475,977; and 6,632,785, the
disclosures of which are incorporated herein by reference for all
purposes. An exemplary water-soluble polymer that can provide a
packaging material that can be used to package the concentrate
includes polyvinyl alcohol. The packaged concentrate can be
provided as unit dose packages or multiple dose packages. In the
case of unit dose packages, it is expected that a single packaged
unit will be placed in a dishwashing machine, such as the detergent
compartment of the dishwashing machine, and will be used up during
a single wash cycle. In the case of a multiple dose package, it is
expected that the unit will be placed in a hopper and a stream of
water will degrade a surface of the concentrate to provide a liquid
concentrate that will be introduced into the dishwashing
machine.
[0093] Suitable water-soluble polymers that may be used in the
invention are described in Davidson and Sittig, Water Soluble
Resins, Van Nostrand Reinhold Company, New York (1968), herein
incorporated by reference for all purposes. The water-soluble
polymer should have proper characteristics such as strength and
pliability in order to permit machine handling. Preferred water
soluble polymers include polyvinyl alcohol, cellulose ethers,
polyethylene oxide, starch, polyvinylpyrrolidone, polyacrylamide,
polyvinyl methyl ether-maleic anhydride, polymaleic anhydride,
styrene maleic anhydride, hydroxyethylcellulose, methylcellulose,
polyethylene glycols, carboxymethylcellulose, polyacrylic acid
salts, alginates, acrylamide copolymers, guar gum, casein,
ethylene-maleic anhydride resin series, polyethyleneimine, ethyl
hydroxyethylcellulose, ethyl methylcellulose, hydroxyethyl
methylcellulose. Lower molecular weight water soluble, polyvinyl
alcohol film-forming polymers are generally, preferred. Polyvinyl
alcohols that can be used include those having a weight average
molecular weight of between about 1,000 and about 300,000, and
between about 2,000 and about 150,000, and between about 3,000 and
about 100,000.
[0094] The composition made according to the present invention may
be dispensed from a spray-type dispenser such as that disclosed in
U.S. Pat. Nos. 4,826,661, 4,690,305, 4,687,121, 4,426,362 and in
U.S. Pat. Nos. Re 32,763 and 32,818, the disclosures of which are
incorporated by reference herein for all purposes. Briefly, a
spray-type dispenser functions by impinging a water spray upon an
exposed surface of the solid composition to dissolve a portion of
the composition, and then immediately directing the concentrate
solution comprising the composition out of the dispenser to a
storage reservoir or directly to a point of use. When used, the
product can be removed from the package (e.g.) film and is inserted
into the dispenser. The spray of water can be made by a nozzle in a
shape that conforms to the solid detergent shape. The dispenser
enclosure can also closely fit the detergent shape in a dispensing
system that prevents the introduction and dispensing of an
incorrect detergent.
[0095] While the invention is described in the context of a
warewashing composition for washing articles in an automatic
dishwashing machine, it should be understood that the warewashing
composition can be used for washing non-ware items. That is, the
composition can be referred to as a cleaning composition and can be
used to clean various items and, in particular, any items that may
suffer from water spotting. Examples of other uses of the
composition of the invention include but are not limited to
automotive washes, window washes, shower stall cleaners, to name a
few. It should be understood that certain components that may be
included in a warewashing composition because it is intended to be
used in an automatic dishwashing machine can be excluded from a
cleaning composition that is not intended to be used in an
automatic dishwashing machine, and vice versa. For example,
surfactants that have a tendency to create quite a bit of foaming
may be used in a cleaning composition that is not intended to be
used in an automatic dishwashing machine.
[0096] The warewashing composition can be provided in several forms
including solids and liquids. When provided in the form of a solid,
the warewashing composition can be provided in the form of powder,
granules, pellets, tablets, blocks, cast solids, and extruded
solids. By way of example, pellets can have sizes of between about
1 mm and about 10 mm diameter, tablets can have sizes of between
about 1 mm and about 10 mm diameter, tablets can have sizes of
between about 1 cm and about 10 cm diameter, and blocks can have
sizes of at least about 10 cm diameter. When provided in the form
of a liquid, the warewashing composition can be provided as a gel
or a paste. Exemplary ranges for components of the warewashing
composition when provided as a gel or a paste are shown in Table 1.
Exemplary ranges for components of the warewashing composition when
provided as a solid are shown in Table 2.
TABLE-US-00001 TABLE 1 Gel or Paste Warewashing Composition (wt. %)
Third First Exemplary Second Exemplary Component Range Exemplary
Range Range Water 5-60 10-35 15-25 Cationic Source 1-60 5-40 10-30
Alkaline Source 1-60 5-40 10-30 Non-Conversion 0-50 0.5-30 2-20
Agent Forming Alkaline Source Stabilizer 0-20 0.5-15 2-10
Dispersant 0-20 0.5-15 2-9 Enzyme 0-15 0.5-10 1-5 Corrosion 0-15
1-10 2-5 Inhibitor Surfactant 0-15 1-10 2-5 Fragrance 0-10 0.01-5
0.1-2 Dye 0-1 0.001-0.5 0.01-0.25
TABLE-US-00002 TABLE 2 Solid Warewashing Composition (wt. %) First
Second Third Exemplary Exemplary Exemplary Component Range Range
Range Water 0-30 1-15 2-8 Cationic Source 1-60 5-40 10-30 Bleach
0-55 15-45 25-35 Alkaline Anionic 1-60 0.5-30 2-20 Source
Non-Conversion 0-50 0.5-30 2-20 Agent-Forming Alkaline Source
Dispersant 0-10 0.001-5 0.01-1 Enzyme 0-15 1-10 2-5 Corrosion
Inhibitor 0-15 1-10 2-5 Surfactant 0-15 1-10 2-5 Fragrance 0-10
0.01-5 0.1-2 Dye 0-1 0.001-0.5 0.01-0.25
[0097] The various forms of the warewashing composition concentrate
can be provided in a water soluble packaging film. That is, solids
and liquids can be packaged in the water soluble films. Exemplary
solids that can be packaged in a water soluble film include
powders, pellets, tablets, and blocks. Exemplary liquids that can
be packaged in the water soluble film include gels and pastes.
TABLE-US-00003 TABLE 3 Exemplary Rinse Agent Compositions
Composition 1, Composition 2, COMPONENT Wt. % Wt. % Cationic Source
Alkaline Anionic Source Sheeting agent 1-90 3-50 Humectant 0-90
3-50 Water 0-90 3-50 Solidification agent 0-90 20-50 Defoamer 0-10
0.1-5 Chelating agent/threshold 0-30 0.1-20 inhibitor pH buffers To
desired pH To desired pH Glass corrosion inhibitors 0-20 0.1-10
[0098] The rinse agent composition may contain the cationic source
in an amount sufficient to provide a desired molar equivalent of
cation to anion in the use composition. Exemplary cationic and
alkaline anionic sources include those discussed above in the
warewashing detergent composition section.
[0099] It is believed that the rinse agent composition can be used
in a high solids containing water environment (in excess of about
200 ppm) in order to reduce the appearance of a visible film caused
by the level of dissolved solids present in the water. The
applications where the presence of a visible film after washing a
substrate is a particular problem include the restaurant or
warewashing industry, the car wash industry, and the general
cleaning of hard surfaces. Exemplary articles in the warewashing
industry that can be treated with a rinse agent include, but are
not limited to: dishware, cups, glasses, flatware, and cookware.
For the purposes of this invention, the terms "dish" and "ware" are
used in the broadest sense to refer to various types of articles
used in the preparation, serving, consumption, and disposal of food
stuffs including, but not limited to: pots, pans, trays, pitchers,
bowls, plates, saucers, cups, glasses, forks, knives, spoons,
spatulas, and other glass, metal, ceramic, plastic composite
articles commonly available in the institutional or household
kitchen or dining room. In general, these types of articles can be
referred to as food or beverage contacting articles because they
have surfaces that are provided for contacting food and/or
beverage. In the car wash industry, filming on the surface of a
washed motor vehicle is undesirable. Accordingly, the rinse agent
is particularly useful for the glass and painted surfaces of a
motor vehicle. Accordingly, the rinse agent can be used to reduce
the occurrence of visible filming on hard surfaces caused by high
solids containing water. Exemplary hard surfaces include, but are
not limited to: glass, vehicle exteriors, ware, counter tops, light
fixtures, windows, mirrors, plastics, clear coats, painted surfaces
including painted metal and painted wood, and treated surfaces
including treated metal and treated wood.
[0100] As an example, when the rinse agent composition is used in
warewashing applications, the rinse agent composition should
provide effective sheeting action and low foaming properties. In
car washing applications, it is desirable for the rinse agent to
provide effective sheeting action. Generally, rinse agents used for
rinsing motor vehicles can tolerate a higher level of foaming than
rinse agents used in warewashing machines.
[0101] The above specification provides a basis for broadly
understanding the invention. The following examples and test data
provide an understanding of certain specific embodiments of the
invention. The examples are not meant to limit the scope of the
invention that has been set forth in the foregoing description.
Variations within the concepts of the invention are apparent to
those skilled in the art.
EXAMPLES
[0102] The following examples were conducted to compare the contact
angle of water based on warewashing compositions of the invention
as compared to pre-existing particle or nanoparticle-containing
compositions. The following procedure was followed to prepare
ceramic tiles for the examples: [0103] 1. Gloves were worn during
washing the tiles to prevent skin oils from contacting the
glassware. [0104] 2. The ceramic tiles were scrubbed thoroughly
with neutral pH liquid dish detergent commercially available as
Express from Ecolab Inc. to remove dirt and oil. [0105] 3. The
tiles were allowed to air dry.
Example 1
[0106] Four controls were prepared. For the first control (A),
ceramic tiles were treated with only sodium hydroxide. For the
second control (B), a tile was treated with 1000 ppm magnesium
chloride, neutral pH. For the third control (C), the tile was
treated with 1000ppm commercially purchased magnesium
hydroxide/oxide nanoparticles. For the fourth control, tile (D) was
treated with 1000ppm calcium chloride, neutral pH. Tiles (E) and
(F) were treated according to the invention. Tile (E) was treated
with 1000ppm water-soluble magnesium chloride under alkaline
conditions to generate magnesium hydroxide in situ. Tile (F) was
treated with 1000ppm water-soluble calcium chloride under alkaline
conditions to generate magnesium hydroxide in situ. After treatment
all tiles were rinsed with 17-grain hard water and dried with a
paper towel. The contact angle of deionized water was measured
using a goniometer. The lower the contact angle of deionized water,
the better the wetting of the surface, and the less likely the
surface will show water spotting. Results are shown in the table
below:
TABLE-US-00004 Contact Angle Tile Treatment (degrees) A Sodium
hydroxide 48 B Magnesium chloride, 28 neutral pH C Commercial
magnesium 15 hydroxide/oxide particles D Calcium chloride, neutral
35 pH E in situ magnesium 14 hydroxide F in situ calcium chloride
18
[0107] The results show that tiles E and F, treated according to
the invention, performed substantially the same as the
nanoparticle-treated tile C and better than tiles B & D that
did not practice the invention.
* * * * *