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Claims  |
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What is claimed is:
1. A liquid floor polish remover composition consisting of:
from about 0.1 percent to about 30 percent by weight of a nonionic
surfactant, said surfactant being selected from the group of nonionic
surfactants which are the condensation products of an alcohol component
having an average of from about 5 to about 11 carbon atoms condensed with
from about 2 to about 8 moles of an alkylene oxide per mole of said
alcohol; from about 0.1 percent to about 30 percent by weight of an
alkalinity builder; up to about 30 percent by weight of a hydrotrope; from
about 0.1 to about 30 percent by weight of an amine; and from about 1
percent to about 99 percent substantially demineralized water, wherein
said alkalinity builder is selected from the group consisting of alkali
metal phosphates, alkali metal silicates, alkali metal carbonates, alkali
metal borates, alkali metal bicarbonates, and combinations thereof.
2. The floor polish remover composition recited in claim 1, wherein said
alcohol component is composed of C.sub.4 to C.sub.20 alcohols selected
from the group consisting of n-butyl alcohol, n-pentyl alcohol, n-hexyl
alcohol, n-heptyl alcohol, n-octyl alcohol, n-nonyl alcohol, n-decyl
alcohol, n-undecyl alcohol, n-dodecyl alcohol, n-tetradecyl alcohol,
isopentyl alcohol, tert-pentyl alcohol and combinations thereof.
3. The floor polish remover composition recited in claim 1, wherein said
alkylene oxide is selected from the group consisting of ethylene oxide and
propylene oxide.
4. The floor polish remover composition recited in claim 1, wherein said
hydrotrope is selected from the group consisting of alkali metal salts of
cumene, benzene sulfonates, xylene sulfonates, toluene sulfonates, alkali
metal phosphonates, alkyl-substituted benzene sulfonates,
alkyl-substituted disulfonates, fatty mono-carboxylic acids, fatty
di-carboxylic acids, 2-cyclohexene-1-octanoic acid, alkyl phosphate
esters, alkylaryl phosphate esters, and amphoteric surfactants.
5. The floor polish remover composition recited in claim 1, wherein said
amine is selected from the group consisting of monoethanolamine,
diethanolamine, triethanolamine, monoisopropanolamine, diisopropanolamine,
triisopropanolamine, 2-amino-2-methyl-1-propanol,
2-aminoethylethanolamine, 2-amino-1-butanol, 2-amino-2-methyl-1-propanol,
2-amino-2-methyl-1,3-propandiol, tris(hydroxymethyl)aminomethane,
2-amino-1-butanol, 2-amino-2-methyl-1-propanol,
2-dimethylamino-2-methyl-1-propanol, diethylethanolamine, ethyl
monethanolamine, ethyl diethanolamine, morpholine, n-methyl morpholine,
n-ethyl morpholine, ethylamine, diethylamine, triethylamine and
combinations thereof.
6. A method of removing floor polish, comprising the steps of:
adding one part of a composition consisting of about 0.1 percent to about
30 percent by weight of a nonionic surfactant, said surfactant being
selected from the group of nonionic surfactants which are the condensation
products of an alcohol having an average of from about 5 to about 11
carbon atoms condensed with from about 2 to about 8 moles of a alkylene
oxide per mole of said alcohol; from about 0.1 percent to about 30 percent
by weight of an alkalinity builder; up to about 30 percent by weight of a
hydrotrope; from about 0.1 to about 30 percent by weight of an amine; and
from about 0.1 percent to about 99 percent by weight substantially
demineralized water to from about one part to about 50 parts water;
mixing said one part of said composition with said one to about 50 parts
water to form a floor polish remover solution;
applying said floor polish remover solution to the surface of a floor, said
floor surface having a layer of floor polish thereon;
allowing said floor polish remover solution to remain on said floor to
dissolve and soften said floor polish such that it can be removed with
mechanical action; and
removing said dissolved or floor polish and said floor polish remover
solution from said floor,
wherein said alkalinity builder is selected from the group consisting of
alkali metal phosphates, alkali metal silicates, alkali metal carbonates,
alkali metal borates, alkali metal bicarbonates, and combinations thereof.
7. The method recited in claim 6, wherein said alcohol component is
composed of C.sub.4 to C.sub.20 alcohols.
8. The method of recited in claim 6, wherein said alkylene oxide is
selected from the group consisting of ethylene oxide and propylene oxide.
9. The method recited in claim 6, wherein said hydrotrope is selected from
the group consisting of alkali metal salts of cumene, benzene sulfonates,
xylene sulfonates, toluene sulfonates, alkali metal phosphonates,
alkyl-substituted benzene sulfonates, alkyl-substituted disulfonates,
fatty mono-carboxylic acids, fatty dicarboxylic acids,
2-cyclohexene-1-octanoic acid, alkyl phosphate esters, alkylaryl phosphate
esters, and amphoteric surfactants.
10. The method recited in claim 6, wherein said amine is selected from the
group consisting of monoethanolamine, diethanolamine, triethanolamine,
monoisopropanolamine, diisopropanolamine, triisopropanolamine,
2-amino-2-methyl-1-propanol, 2-aminoethylethanolamine, 2-amino-1-butanol,
2-amino-2-methyl-1-propanol, 2-amino-2-methyl-1,3-propandiol,
tris(hydroxymethyl)-aminomethane, 2-amino-1-butanol,
2-amino-2-methyl-1-propanol, 2-dimethylamino-2-methyl-1-propanol,
diethylethanolamine, ethyl monethanolamine, ethyl diethanolamine,
morpholine, n-methyl morpholine, n-ethyl morpholine, ethylamine,
diethylamine, triethylamine and combinations thereof. |
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Claims  |
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Description  |
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FIELD OF THE INVENTION
The present invention relates generally to compositions which are applied
to floor surfaces and, more specifically, to compositions which are
suitable for use in removing layers of dull, aged floor polish from floor
surfaces.
BACKGROUND OF THE INVENTION
Numerous brands of floor polish, also commonly referred to as floor waxes,
are available commercially. The ingredients and the relative proportions
of ingredients vary widely among the brands, but most include acrylic
copolymers which are chemically crosslinked, typically with zinc. Most
floor polishes also contain natural and/or synthetic waxes, natural and/or
synthetic resins and other performance ingredients such as but not limited
to coalescing agents, plasticizers, surface active agents, and defoamers.
Although commercial floor polishes are generally sold as liquids, dry
compositions are also known. In use, floor polishes are applied to floor
surfaces which may be vinyl, and vinyl composition tile, linoleum, ceramic
tile, sealed wood, or one of the many other hard or resilient flooring
materials currently available. When dry, the layer of floor polish is
often buffed to yield a desirable shine to the flooring. The shiny acrylic
or wax layer provides a barrier to protect the flooring material from
spills and the like and resists scuffing.
However, after repeated contact with dirt and other soils such as that
deposited by pedestrian traffic, and as a result of repeated cleaning with
hard surface cleaners, an originally shiny layer of polish loses its gloss
and clarity, becoming dull, scratched, sometimes yellowed and soiled with
ground-in dirt. Hence, after extended periods it becomes necessary to
remove the aged layer of polish so that it can be replaced with a new
layer. The removal of floor polish from floor surfaces has in the past
generally been achieved through the use of strong solvents such as glycol
ethers contained in fully-built floor polish removers. These conventional
floor polish removers also typically contain ammonia. It was previously
believed that these strong solvents and ammonia, or very high pH, were
necessary to substantially remove the aged layer of polish due to its
inherent ability to resist degradation. In particular, floor polishes
which include acrylic polymers having zinc crosslinkages are formulated to
resist detergents and are thus extremely difficult to remove. Polish
removers containing solvents and ammonia disrupt the zinc crosslinkage
such that the ammonia forms coordination compounds with the zinc and the
solvents soften the polymers. Other ingredients then remove the disrupted
acrylic polymers.
For a number of reasons, consumer preference for floor polish removers has
turned away from the use of strong solvents and ammonia. In particular,
the strong ammoniacal odor associated with ammonia-containing compositions
are undesirable. However, performance, convenience of use, and economy are
still significant concerns to the consumer.
Therefore, it would be desirable to provide a floor polish remover which
conveniently and effectively removes a layer of floor polish and which
does not contain ammonia or strong solvents such as glycol ethers both of
which have undesirable strong odors. It would also be desirable to provide
such a floor polish remover which is particularly effective in removing
floor polishes containing acrylic polymers. It would further be desirable
to provide a convenient, economical method of manufacturing such a floor
polish and the simple method of using such a polish. The present invention
achieves these goals.
SUMMARY OF THE INVENTION
It has now been discovered that a high-performance floor polish remover
composition may be formulated without the use of strong solvents such as
glycol ethers and without ammonia. In accordance with the present
invention there is provided a floor polish remover composition which, in
liquid form, comprises a low molecular weight nonionic surfactant, an
alkalinity builder, a hydrotrope, an amine, and demineralized water. In
another aspect, by eliminating the water component from the present
invention, a dry floor polish remover is provided. The inventive floor
polish remover composition is exceptionally effective in removing dull,
aged floor polish from floor surfaces which is known to be particularly
difficult to remove. Hence, the present invention provides a floor polish
remover which does not contain undesirable glycol ether solvents and which
does not give off unwanted ammonia vapors.
The nonionic surfactant component of the present invention comprises the
condensation products of aliphatic alcohols having an average of from
about 5 to about 11 carbon atoms condensed with from about 2 to about 8
moles of an alkylene oxide per mole of aliphatic alcohol. The specific
aliphatic alcohols which are used to obtain the 5 to 11 carbon atom
average are those aliphatic alcohols which have a carbon atom chain of
from about 4 carbon atoms to about 20 carbon atoms. In the liquid
embodiment of the present invention, a nonionic surfactant comprises from
about 0.1 percent to about 30.0 percent by weight of the floor polish
remover composition; an alkalinity builder comprises from about 0.1
percent to about 30.0 percent by weight of the composition; a hydrotrope
comprises up to about 30.0 percent by weight of the composition; an amine
comprises from about 0.1 percent to about 30.0 percent by weight of the
composition; and substantially demineralized or "soft" water comprises
from about 1.0 percent to about 99.0 percent by weight of the composition.
It is to be understood that mixtures of surfactants, alkalinity builders,
hydrotropes, and amines of the categories described herein may be used in
the present invention. That is, it is not necessary that the novel
composition contain only a single kind of nonionic surfactant, alkalinity
builder, hydrotrope, and amine.
In the embodiment of the present invention which is a dry mixture, a
nonionic surfactant comprises from about 1 percent to about 30 percent by
weight of the floor polish remover composition; an alkalinity builder
comprises from about 1 percent to about 97 percent by weight of the
composition; and, an amine comprises from about 1 percent to about 30 by
weight of the composition. Again, it is not necessary that the dry
composition contain only a single type of nonionic surfactant, alkalinity
builder, hydrotrope, and amine.
By using ethoxylated nonionic surfactants in the present invention which
have a relatively low average molecular weight, unexpected superior floor
polish removing performance has been achieved which is equal to and often
exceeds the performance of ammoniated floor polish removers containing
undesirable solvents.
In another aspect, the present invention provides a method of preparing the
floor polish remover composition which, in liquid form, comprises the
steps of mixing the alkalinity builder with the demineralized water,
adding and mixing the amine with the mixed alkalinity builder and water,
adding and mixing the hydrotrope to the mixture of alkalinity builder,
amine and water, and then adding and mixing the nonionic surfactant into
the mixture. In the dry form of the present invention, the method of
preparing the floor polish remover includes the steps of adding a liquid
amine to a dry carrier such that the amine and the carrier form a dry
composition, adding a liquid nonionic surfactant to a dry carrier such
that the nonionic surfactant and the carrier form a dry composition, and
mixing the alkalinity builder, the dry amine/carrier composition and the
dry nonionic/carrier composition.
The present invention further includes a method of using the floor polish
remover composition of the present invention. In the liquid form, the
method includes the step of mixing the liquid floor polish remover with
water in a ratio, in parts per volume, of one part liquid floor polish
remover to about one part to about fifty parts water. In the dry floor
polish remover composition, the method of the present invention includes
mixing one part of the dry composition with about two to about fifty parts
water in parts per volume.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The novel floor polish remover composition of this invention includes in
its liquid form five ingredients. The first ingredient is a low molecular
weight ethoxylated nonionic surfactant. The nonionic surfactants used
herein are produced by the condensation of an alkylene oxide, preferably
ethylene oxide, with an aliphatic alcohol. The aliphatic alcohol is a
mixture of alcohols having a carbon chain of from about 4 carbon atoms to
about 20 carbon atoms to produce a low molecular weight alcohol having an
average of from about 5 to about 11 carbon atoms. Alternatively, the
alcohol moiety may be a single alcohol within this C.sub.5 to C.sub.11
carbon atom range. That is, the alcohol moiety has an average of from
about 5 to about 11 carbon atoms and includes one or more alcohols having
a carbon chain length of from about C.sub.4 to about C.sub.20. The alcohol
carbon chain may be straight or branched. Preferred alcohols for use
herein in forming the nonionic surfactants of the present invention
include n-butyl alcohol, n-pentyl alcohol, n-hexyl alcohol, n-heptyl
alcohol, n-octyl alcohol, n-nonyl alcohol, n-decyl alcohol, n-undecyl
alcohol, n-dodecyl alcohol and n-tetradecyl alcohol. Various branched low
molecular weight alcohols having an average of from about 8 to about 11
carbon atoms may be suitable such as isooctyl alcohol and tert-nonyl
alcohol.
The alkylene oxide component used in forming the low molecular weight
nonionic surfactants for use in the present invention is, as stated,
preferably ethylene oxide, although propylene oxide may be suitable in
some applications. The quantity of ethylene oxide used in forming the low
molecular weight nonionic surfactants of the present invention is from
about 2 moles to about 8 moles and preferably from about 2 moles to about
6 moles of ethylene oxide per mole of alcohol. Particularly effective low
molecular weight nonionic surfactants for use in the present invention are
the condensation products bounded by the following four compounds,
condensation products of 1 mole of an 8 carbon average alcohol and about 2
moles of ethylene oxide, 1 mole of an 8 carbon average alcohol with about
6 moles of ethylene oxide, one mole of an 11 carbon average alcohol with
about 2 moles of ethylene oxide, and 1 mole of an 11 carbon average
alcohol with about 6 moles of ethylene oxide. It has been found that the
low molecular weight nonionic surfactants used in this invention provide
unexpected and superior floor polish removing performance.
The low molecular weight nonionic surfactants comprise from about 0.1
percent to about 30.0 percent by weight, preferably from about 5.0 percent
to about 15 percent by weight, and most preferably about 10.0 percent by
weight of the liquid floor polish remover composition of the present
invention. Although the liquid form of the present invention is preferred,
a dry formulation is also provided. Low molecular weight nonionic
surfactants comprise from about 1.0 to about 30.0 percent, and preferably
from about 5.0 to about 15.0 percent by weight of the dry floor polish
remover composition of the present invention.
The second component of the floor polish remover composition of the present
invention is an alkalinity builder. Alkaline builders preferred for use in
the present invention include alkali metal phosphates such as
orthophosphates, pyrophosphates, tripolyphosphates, and
hexametaphosphates, specific examples of which include tetrasodium
monohydrogen tripolyphosphate, trisodium dihydrogen tripolyphosphate,
sodium tripolyphosphate, tetrapotassium pyrophosphate, and potassium
tripolyphosphate. It may be preferable in some applications of dry
formulations to hydrate the phosphate compound and hydrated sodium
tripolyphosphate is especially preferred for use herein. The alkaline
builders used herein may include silicates, preferably alkali metal
silicates such as sodium and potassium silicates. Sodium silicates which
have a SiO.sub.2 :Na.sub.2 O ratio of from 0.5:1 to 4:1 are preferred for
use herein. Alkalinity builders preferred for use in the present invention
also include alkali metal carbonates, borates, bicarbonates, and sulfates.
Specific examples of which include the sodium and potassium tetraborates,
perborates, bicarbonates and carbonates.
Stronger alkaline materials such as sodium or potassium hydroxide may be
used as alkaline builders in the present invention. Citrates, such as
sodium citrate, are useful as alkaline builders as are
carboxymethyloxysuccinates and nitrilotriacetates. Ethylene diamine
monoacetate, diacetates, triacetates and tetraacetates are also useful as
alkalinity builders herein. The alkaline builders of the present invention
may also include polymeric polyelectrolytes such as polyacrylates,
polymaleates, polymethacrylates, polyacrylamides and copolymer of these
compounds.
The alkalinity builder of the present invention comprises from about 0.1
percent to about 30.0 percent by weight and preferably from about 1.0
percent to about 10.0 percent by weight of the liquid floor polish remover
composition of the present invention. The preferred alkaline builders
comprise from about 1.0 percent to about 97.0 percent by weight and
preferably from about 1.0 percent to about 10.0 percent by weight or
higher if used as a carrier of the dry floor polish remover composition of
the present invention. The alkalinity builders used in the present
invention may be used alone or in combination with one another. Especially
preferred for use herein are the phosphates, silicates, carbonates and
borates. Of these, the silicates are most preferred for use herein.
Hydrated sodium metasilicate has been found to be extremely desirable for
use as the alkalinity builder of the present invention.
The third ingredient of the present invention is a hydrotrope. Hydrotropes
preferred for use herein include etanolamines. Other hydrotropes preferred
for use herein are the alkali metal salts of cumene, benzene sulfonates,
xylene sulfonates, and toluene sulfonates. Alkali metal phosphonates,
alkyl-substituted benzene sulfonates and disulfonates, fatty mono and
dicarboxylic acids, such as 2-cyclohexene-1-octanoic acid,
alkyl-substituted sulfosuccinates, and alkyl-substituted naphthalene
sulfonates are also preferred hydrotropes for use in the present
invention. Also suitable for use as hydrotropes in the present invention
are alkyl and alkylaryl phosphate esters. Also, amphoteric surfactants
such as glycinates, propionates and betaines are useful herein.
The preferred hydrotropes may be used herein alone or in combination with
each other and comprise up to about 30.0 percent by weight, preferably
from about 0.1 to 10.0 percent by weight and most preferably from about
2.0 to 8.0 percent by weight of the liquid floor polish remover
composition of the present invention.
The fourth ingredient of the present invention is an amine. It may be
possible in some applications to increase the concentration of the
alkalinity builders in the present composition and decrease or eliminate
the amine component. Suitable amines for use in the present invention
include but are not limited to monoethanolamine, diethanolamine,
triethanolamine, monoisopropanolamine, diisopropanolamine,
triisopropanolamine, 2-amino-2-methyl-1-propanol,
2-aminoethylethanolamine, 2-amino-1-butanol, 2-amino-2-methyl-1-propanol,
2-amino-2-methyl-1,3-propandiol, tris(hydroxymethyl)-aminomethane,
2-amino-1-butanol,
2-amino-2-methyl-1-propanol,2-dimethylamino-2-methyl-1-propanol,
diethylethanolamine, ethyl monethanolamine, ethyl diethanolamine,
morpholine, n-methyl morpholine, n-ethyl morpholine, ethylamine,
diethylamine, triethylamine. Particularly preferred is monoethanolamine.
Ammonia is also suitable.
The amine component of the present invention comprises from about 0.1
percent to about 30.0 percent by weight and preferably about 5 percent by
weight of the liquid floor polish remover of the present invention. In the
dry floor polish remover composition of the present invention, an amine
comprises from about 0.1 percent to about 30.0 percent by weight of the
composition. It is to be understood that a single amine or a combination
of the preferred amines may be used as the amine component of the present
invention.
The fifth ingredient of the present invention, in the liquid composition,
is substantially deionized or demineralized water. Demineralized water
comprises from about 1.0 percent by weight to about 99.0 percent of the
floor polish remover by weight and preferably from about 70.0 percent to
96.0 percent by weight of the composition. The degree of hardness of the
water as grains of calcium carbonate per gallon of water should preferably
but need not be less than about 5 grains per gallon. In dry formulations,
a suitable carrier would be substituted for water. Suitable carriers would
include but are not limited to alkali metal salts of phosphates, sulfates,
carbonates and borates.
The present invention also includes a method of preparing the floor polish
remover of the present invention which, in its liquid form, comprises the
steps of mixing in a container the alkalinity builder with the
demineralized water, adding and mixing the amine with the mixed alkalinity
builder and water, adding and mixing the hydrotrope to the mixture of
alkalinity builder, amine and water, and adding and mixing the nonionic
surfactant into the mixture. In the dry form of the present invention, the
method of preparing the floor polish remover includes the steps of adding
a liquid amine to a dry carrier such that the amine and the carrier form a
dry composition, adding the nonionic surfactant to a dry carrier such that
the nonionic surfactant and the carrier form a dry composition, and mixing
the alkalinity builder, the dry amine/carrier composition and the dry
nonionic/carrier composition together to form the final dry floor polish
remover composition. The preferred dry carrier is a phosphate compound
such as sodium tripolyphosphate or a carbonate such as sodium carbonate
although other suitable carriers such as sodium sulfate will be known to
those skilled in the art.
The present invention further includes a method of using the floor polish
remover composition which includes, in the liquid form, the step of mixing
the liquid floor polish remover with water in a ratio in parts per volume
of one part liquid floor polish remover with about one part to about fifty
parts water and most preferably about five parts water. In the dry floor
polish remover composition, the method of the present invention includes
mixing one part of the dry composition with about two to about fifty parts
water by volume.
A further understanding of the present invention will be obtained from the
following specific examples which are intended to illustrate the invention
but not to limit the scope thereof, parts and percentages being by weight
unless otherwise indicated.
EXAMPLES
The following floor polish remover performance tests were conducted using
various low molecular weight nonionic surfactants which were the products
of short-chain aliphatic alcohols condensed with ethylene oxide. The floor
polish remover compositions tested had the following formulations.
Percentages are by weight unless otherwise indicated:
10%: Nonionic Surfactant
5%: Monethanolamine
5%: Sodium Meta Silicate.5H.sub.2 O
5%: Hydrotrope (2-cyclohexane-1-octanoic acid)
75%: Soft Water
For each test, a single coat of a detergent-resistant floor polish was
applied to a floor tile. The polish was then air-dried and aged
twenty-four hours. In order to obtain a reference standard, the above
formulation was prepared using Alfonic 610-50R as the nonionic surfactant.
Alfonic 610-50R is a nonionic surfactant prepared by the condensation of
aliphatic alcohols having from 6 to 10 carbons with an average of 50
percent by weight or an average of 3.3 moles of ethylene oxide. This
formulation was diluted one part floor polish remover to five parts water
and the diluted floor polish remover was then applied to the polished
floor surface and its effectiveness in removing the dried polish
determined using a Gardiner scrubability machine. Effectiveness was
evaluated visually by a panel of evaluators. This test is a modification
of ASTM test procedure D-1792-82. The observation was then divided into
the results of the remaining tests and multiplied by 100 to express
results as percent of the reference standard. Those test formulations
which were less effective in removing the sample floor polish remover than
the Alfonic 610-50R formulations are expressed as percentages less than
100%. Those test formulations which were more effective in removing the
sample floor polish remover than the Alfonic 610-50R formulation are
expressed as percentages greater than 100%.
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Average
Carbon Chain
Average
Relative
Test No.
Trademark Supplier Length Moles EO
Performance
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(%)
1 ALFONIC 610-50R
Vista Chemical Company
8.7 3.3 100
2 NONANOL 2EO Shell Chemical Company
9 2 96
3 NONANOL 3EO Shell Chemical Company
9 3 103
4 NONANOL 6EO Shell Chemical Company
9 6 97
5 NEODOL 91-2.5
Shell Chemical Company
10.1 2.5 107
6 NEODOL 91-6 Shell Chemical Company
10.1 6 85
7 ALFONIC 810-50
Vista Chemical Company
9.1 3 109
8 ALFONIC 810-60
Vista Chemical Company
9.1 4.9 106
9 ALFONIC 610-60
Vista Chemical Compnay
8.7 4.5 85
10 MACOL 212 Mazer Chemicals, Inc.
6 3 74
11 HEXYL CELLOSOLVE
Union Carbide Corp.
6 1 91
12 ETHANOL Commodity 2 0 24
13 BUTYL CELLOSOLVE
Union Carbide Corp.
4 1 36
14 DOWANOL DB Dow Chemical 4 2 53
15 MACOL 229-16 Mazer Chemicals, Inc.
4.6 4.5 41
16 ALFOL 810 Vista Chemical Company
9.1 0 21
17 NONANOL 9EO Shell Chemical Company
9 12 67
18 NEODOL 25-3 Shell Chemical Company
13.2 3 46
19 NEODOL 25-7 Shell Chemical Company
13.2 7.2 43
20 NEODOL 25-12 Shell Chemical Comapny
13.2 12 56
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While the invention has been described in conjunction with specific
embodiments thereof, it is evident that many alternatives, modifications,
and variations will be apparent to those skilled in the art in light of
the foregoing description. Accordingly, it is intended to embrace all such
alternatives, modifications and variations as fall within the spirit and
broad scope of the appended claims.
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Description  |
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