Note: Descriptions are shown in the official language in which they were submitted.
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COATING REMOV~R AND WOOD RESTORATIVE COMPOSITIONS
AND METHODS OF USING SAME
Backqround of the Invention
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This invention relates to a composition and
method for removal of both oil- and water-based paints,
stains, varnishes, lacquers, clear resins and enamels
from interior and exterior surfaces. It also relates to
a surface wood restorative composition and to a composi-
tion for preparing the surface of old, weather-beaten or
water-stained wood to accept a new finish, as well as to
methods of accomplishing the same. It further relates
to a composition for removing heavy grease and oil
buildups, and to a composition for dissolving and remov-
ing wood pitch, resin, and creosote deposits, and tomethods of accomplishing the same.
Most paint removers on the market today employ
toxic petroleum distillates or other volatile agents,
such as toluene, methylene chlorlde, ketones, or acetone
as their active ingredient and consequently require
great care in handling and applying, including provi-
sions for adequate ventilation.
Another problem with such paint removers is
that it is usu~lly necessary to reapply the paint
remover several times if one wishes to strip several
layers of paint; in other words, often one must effec-
tively apply one layer of paint remover for each layer
of paint which is sought to be removed. Moreover, in
uqe, such product~ tend to dry quickly, thereby causing
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them to lose their stripping ability and rendering them
unsuitable for use on exterior s~rfaces which are
exposed to the elements. This same volatility causes
them to be hazardous when exposed to hiqh temperature
S and open flames. Still other problems associated with
~uch compositions are that they are generally non-
biogradable, herbicidal, and often may not be completely
removed without the introduction of another solvent.
Removers employing alkaki metal hydroxides and
sodium carbonate are well known. See, for example, U.S.
Patent Nos. 1,449,388, 1,581,413, and 1,589,219. How-
ever, in addition to suffering from many of the draw-
backs noted above, such compositions have tended to burn
wood surfaces, to dry too quickly on exterior surfaces,
and to be so corrosive as to be extremely hazardous to
the user.
A similar situation exists with products
currently available for removal of heavy grease and oil
buildups and for removal of wood pitch, resin, and
creosote deposits~ The vast majority of the commer-
cially marketed products intended for theqe applications
alcço employ toxic petroleum distillates or other vola-
tile agents as their active ingredient and consequently
require great care in handling and applyinq, including
provisions for adequate ventilation. The volatility of
the active ingredients also causes them to be quite
hazardous when exposed to hiqh temperature and open
flames. This is especially significant in many indus-
trial settings. These products also generally tend to
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be non-biodegradable, herbicidal, and require use of
another solvent for their complete removal. Alkaline
products currently available for removal of heavy qrease
and oil buildups or for removal of wood pitch, resin,
and creosote deposi~s of~en suffer from many of the
drawbacks noted above, and also tend to be so corrosive
as to be extremely hazardous to the user.
It is therefore an ohject of this invention
to provide inexpensive, nonflammable, biodegradable, and
nonherbicidal paint remover and wood restorative com-
positions which are relatively gentle to use, will
remain wet and therefore effective for long periods,
and that are suitable and safe for use on interior and
exterior surfaces~
It is a further object of the present inven-
tion to provide a fast-actinq remover which i9 effective
on deteriorated surfaces in a single application and
which may be removed either by simply spraying with
water or by methods using very little or no water.
It is still another object of the present
invention to provide a paint remover composition which
i~ not harmful to wood, which acts as a wood restorative,
and which is extremely stable with a long ~helf life.
It is a further object of this invention to
provide inexpensive, biodegradable, nonherbicidal, and
gentle-to-u~e compositions for the removal of heavy
grea~e and oil buildups, as well as for the removal of
wood pitch, resin, and creosote accumulations.
,
It is still another object of the present
invention to provide improved proce3ses for removing
oil- and water-based paints, stain~, varnishes and
resins from any sur~ace and for either renewing or
preparing the surface of old, weather-beaten or water-
stained wood.
It is a still further ob~ect of this invention
to provide methods for the safe and effective removal of
oil and grease buildups, as well as methods for the safe
and effective removal of wood pitch, resin, and creosote
deposits.
These and other objects are accomplished by
the compositions of the present invention and by the
methods of using the same, all of which are described
more particularly below.
Summary of the Invention
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There are several aspects to the present
invention. One aspect comprises two different aqueous
compositions, the essential ingredients of which are an
alkali metal hydroxide, sodium bicarbonate~ glycerol,
ethylene glycol, and xanthan gum.
The compositions thu~ provided can be easily
and safely applied with a brush, roller or spray. One
of the two compositions will remove multiple layers of
deteriorated oil- and water-based paints, heavy-bodied
stain~, varnishes, and clear resin finishes without
reapplication in two hours or less. The other of the
two compositions will restore old, weathered wood to
like-new appearance and will remove semi-transparent
stains, both in an hour or less and without reapplica-
tion. Both compositions may be ea~ily and safely washed
off with water as they are fully water soluble, nonherb-
icidal, and biodegradable. Both compositions can also
be removed by essentially waterless means, such as a
spatula, rag, or sponge, which feature is particularly
important for interior applications.
The compositions of the present inventlon will
not damage wood surfaces in any way other than an occa-
sional darkening effect, in fact, a rather surprisingquality is that they actually restore old wood which has
been water-stained, weather-beaten, or rust-stained, and
gives it a new-wood look, thus functioninq both as a
wood re~torative composition and a compos~tion for
preparing such wood to accept new finishe~.
The coating removal and reqtorative composi-
tionR of the present invention comprise aqueous composi-
tion~, the eq~ential ingredients of which are an alkali
metal hydroxide, sodium bicarbonate, glycerol, and
ethylene glycol. Xanthan gum may be added in various
amounts to achieve a thickening action as appropriate
for the specific use and method of application. A
foaming agent such as the reaction product of nonyl
phenol and ethylene oxide and/or a stabilizing agent
such as the conden3ation reaction product of ethylene
oxide and coconut fatty acid monoethanolamide may also
be added to enhance clinging ability to vertical ~urfaces
and to enhance penetration of certain coatingsO
Another aspect of the present invention i~ the
u~e of a second, weakly acidic, oxalic acid composition
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in conjunction with the paint remover and wood restora-
tive composition~ disclosed herein, the use of ~uch an
acidic composition greatly enhancing the removal and
restorative properties of such compositions.
The compositions thus provided can be ea~ily
and safely applied by a number of methods, including
bru~h, roller, and sprayer, will soften and remove heavy
grease or oil buildups, wood pitch, urea and phenolic
reqins, and creosote deposits, and may be easily and
safely wa3hed off with water as they are ~ully water
~oluble, nonherbicidal, and biodeqradable. AnA, as
mentioned above, the composition~ can also be removed
by essentially waterless means, ~or example, with a
resilient spatula, rag, or sponge.
Detailed Description of the Invention
The preferred embodiments of the compositions
of the invention consist essentially of aqueous solu-
tions of the ingredients noted below in the following
approximate weight percentages:
Wood Wood Pitch~
Restorative Oil and Resin, and
Paint and Stain Grea~e Creosote
Remover Remover RemoverRemover
Alkali Metal
Hydroxide7.0% 4.7~ 7.0%10.0%
25 Sodium
~icarbonate 0.5% 0.5% 0~5% 0.5
Ethylene
Glycol 1~0% 1.0% 1.0~1.0~
GlycerolOnl% 0~1% 0~1%0~1%
Xanthan Gum 1.0% 1.0~ 0.9% 007%
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~%6~16~3~
The compositions of the present invention are prepared
by combining and vigorously mixing the above ingredient~
in a container at ambient temperature and pres~ure.
Although 4.7% by weight alkali metal hydrox~de
such as sodium or pota~sium hydroxide is preferred for
the wood restorative composition, any amount between
about 1~5% and 5% will do. Compositions with les~
than about 3.5% to about 4% by weight alkali metal
hydroxide have been found to be effective purely as a
wood restorative, whereas compositions with between
about 3.5% to about 4% and about 4.5% to about 5% by
weight alkali metal hydroxide can function both as a
wood restorative and as a semi-transparent stain
remover, respectively. Compositions containing about 5%
to about 15% by weight alkali metal hydroxide have been
shown to be effective as a paint remover, although about
7~ is preferred for most uses.
Compositions consisting essentially of the
~ame formulation as for the paint remover have been
found to be effective as a grease and oil remover. As
with the paint remover, the amount of alkali metal
hydroxide can be varied from about 5% to about 15~ by
weight, depending on the intended use. The amount of
xanthan gum may be reduced slightly to provide a less
vi5cous formulation.
Removal of wood pitch, resin, and creo~ote
30metimes reguires more alkali metal hydroxlde, but
again the content can vary from about 7% to about 15% by
weight while still achieving satisfactory results. With
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increased alkali metal hydroxide concentration, the
amount of xanthan gum must be reduced to control
gelation tendencies.
For all of the compositions described above,
S test results show sodium hydroxide and potassium hydrox-
ide to function equally well. They may be con~idered to
be interchangeable, or they may be used in combination.
Also, it has been found that the amount of ethylene
glycol and glycerol present in the compositions can be
increa3ed or decreased somewhat an~ the composition~
will still function satisfactorily in some situationsO
If the ethylene glycol and/or the glycerol is/are elim-
inated completely, the compositions tend to dry more
quickly and lose some of their penetrating ability~
If either or both of these ingredients is increased
substantially, hydration reactions of the xanthan gum
become greatly retarded. Therefore, while the stated
amounts are preferred, amounts from about 0.1% up to
about 5~0~ by weight ethylene glycol and from about
0.05~ to about 1.0~ by weight glycerol may be employed
with varying degrees of success.
Although 0.7 to 1% by weight xanthan gum is
preferred, any amount between about 0.2% and about 3~
will do, depending upon the specific intended use. For
some uses, a composition containing only about 0~2%
xanthan gum is especially effective when u~ed with a
spray apparatus such as a pistol-grip sprayer. The
function of xanthan gum is as a thickener and a
stabilizer, while also imparting an improved adherin~
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quality to the compositions so that they tend to better
adhere to vertical and sloped surfaces~ The preferred
xanthan gum is made by Pfizer Chemical Co. and sold
under the name "Flocon S" (a trademark).
The compositions of the present invention work
equally well on virtually any surface, including wood,
metal, stucco and brick. On extremely hot days or when
otherwise exposed to high temperatures, if the com-
positions of the present invention dry out and become
inactive, they can simply be misted with water and thus
reactivated without requiring application of another
coating. Even without reactivation by rewetting, the
compositions will remain wet and active for one to ~wo
hours even in summer. This makes the compositions well
suited for removal of multiple layers of paint or heavy
buildups of grease, wood pitch, resin, or creosote over
long periods o time under hot, dry conditions.
The remover compositions are applied to the
surface from which one desires to remove paint, stain,
varnish, grease, oil, wood pitch, resin, or creosote
by simply applying with a brush, roller or by spraying.
~ ; The composition begins to act on deteriorated finishes
; or coatings almost immediatelyO Based upon field tests
using the preferred compositions noted above, typical
tlmes or treatment o~surfaces or for removal of
various types of coatings were as follows:
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Composition and Coating _emoval Time
Paint Remover Compo~ition
Flat latex pain~ 15 to 120 min
Latex enamel 20 to 120 min
Oil-based hou~e paint 15 to 60 min
Oil-based enamel (other than gloss) 15 to 60 min
Oil-based enamel (gloss) 30 to 120 min
Heavy-bodied latex wood stain 10 to 60 min
Solid-bodied oil wood stain 10 to 40 min
Iron oxide primers 30 to 120 min
Wood Restorative Composition
Bare, weathered wood 1 to 15 min
Semi-transparent oil wood stain 5 to 45 min
Semi-transparent latex wood stain 5 to 60 min
Grease Remover Composition
Bunker C (No~ 6 res;dual) oil
buildup on machinery sur~aces 30 min to 4 hr~
Wood Pitch, Resin, and Creosote Remover
Composition
Wood Pitch 10 min to 2 hrs
Urea or Phenol;c Resin 30 min to 24 hr~
Creosote 6 hrs to 24 hrs
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The compositions of the present invention
often have been found to actually dissolve the paint,
3tain, grease, wood pitch, resin, or creosote sought to
be removed rather than stripping it off layer by layer.
In some instanceq, the compositions penetrate the coat-
ing and attack the bond between the coating and the
underlying sur~ace, allowing the coating to be easily
removed. This means that a single application is typi-
cally enough to completely remove several layers of
coating~ on a surface. The reaction product of the com-
positions and the dissolved coating is water-soluble and
80 may be removed by simply washing with water, since
it is nonherbicidal and fully biodegradable, it may be
washed directly onto lawn or other shrubs with no adverse
consequence~. In interior areas, or other areas where
wa~hing wîth water is not practical, the compo~itions
may be removed with a resilient spatula, putty knife,
rag, or ~ponge, thus requiring essentially no water.
Since the by-product of the paint remover com-
position of the present invention and a paint or staini3 water-soluble~ the invention is also ideal for uqe as
; a paint bru~h or roller cleaner and restorer~ The paint
brush or roller can simply be soaked in the paint
remover~composition until all paint is removed. The
brush or roller can then simply be rinqed with water.
The paint remover composition of the pre~ent
invention has been ~ound to be especially useful in
removing deteriorated coatin~s from aluminum surfaces
and, concurrently, aiding in preparation of the surface
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for a new coating by etching the surface~ The compoqi-
tion has also been shown to be e~ctive in etching
epoxy-painted surfaces in preparation for re-coating.
The paint remover composition has al~o been
found to be effective for a variety of industrial uses,
including: removal of hard lime-dust buildups (4 to 24
hours); removal of asphalt lumps and splashes from equip-
ment (1 to 2 hours): removal of road tar (20 minute~ to
2 hours); removal of fungi, algae, and rnoss from hard
~urfaces (10 minutes to 1 hour), removal of pulp and
paper industry black liquor deposits (10 minutes to 2
hours), and removal of resin glues (4 to 24 hours). The
composition is applied to the coating to be removed,
allowed to remain on the coating for the stated period
of time, and then removed by washing with water or by
essentially waterless methods.
The action of the paint remover compo~ition of
the present In~ention is enhanced considerably by the
application of a second, weakly acidic composition to
the surface following treatment with the remover compo-
sition. The acidic composition comprises an aqueous
solution of oxalic acid, containing from approximately
2~ to approximately 6~ by weight of the acid. The
oxalic acid solution may be applied by any convenient
means, such as a brush, roller or sprayer, and may be
allowed to remain on the surface indefinitely, or may be
rinæed off with water after a period of at least 20 to
30 minutesO
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The wood restorative composition acts to
restore a new-wood look to the surface of old, weather-
beaten or water-stained wood and so prepare the surface
for a new finish by simply applying it by bru~hing,
rolling or ~praying on the surface and allowing it to
remain for about 1 to 15 minutes, then hosing it off
with water. Because the composition does not damage the
~urface of the wood other than an occasional darkening
effect, it may be allowed to remain on the surface for
up to an hour or two without adverse effects.
An even brighter new-wood look is obtained by
applying a second, weakly acidic composition to the sur-
face following treatment with the above wood re~torative
compo~ition, the acidic composition acting to remove
any darkening caused by the alkaline wood re~torative
composition~ The acidic composition in thi~ case al~o
comprises an aqueous solution of oxalic acid, containing
from about 2~ to about 6% by weight of the acid and may
be applied and removed in the same manner as previously
described~
The grea~e removal composition is particularly
effective in dissolving and removing heavy buildups
and/or multiple layers of stubborn greasy or varnish-
like re~idues that have been resistant to other removal
~25 method~. The composition may be applied by brushing,
wiping, rolling, or spraying on the surface. For large
and/or irregularly shaped surface~, ~praying has proven
to be e~pecially effective and con~enient. After a
period of from about 30 minutes to about four hourq, the
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compositions may he removed, along with the dissolved or
softened grease buildup, by hosing it off with water.
high-pre3~ure water ~pray i~ e~pecially q~ick and effec-
tive for removing the composition. As discussed pre-
viously for the paint removal composition, the grea~eremoval composition may also be removed by waterless
means such as wiping. Becau~e the compo~ition is non-
flammable, nonherbicidal, and relatively gentle to u~e,
it is much 3afer in certain industrial environments than
solvent cleaners or harsh caustic cleaners~
Similarly, the wood pitch and re~in removal
composition i~ quite effective in di~olvlng and remov-
ing stubborn buildup~ or coatings of wood pitch or
resins. ~s de~cribed above, the composition may be
applied by bru~hing, wiping, rolling, or spraying on the
surface. After a period of from about 10 minutes to
about 24 hours, depending on the specific application,
the composition may be removed by spraying with water or
by using waterless methods. Using the composition on
heated surface~, such as veneer plant wood driers, has
been ~hown to be e~pecially ef~ective for removal of
pitch and wood resin buildups.
This composition has also been shown to be
effective in removing even glazed, burned-on creoqote
deposit~3 from chimneys. This type of creo~ote is
referred to in the chimney-cleaning trade as "third-
degree" creosote, and is nearly impossible to remove
u~ing methods currently available. The composition is
applied to the creosote deposit by any convenient means,
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such as spraying, and allowed to completely dry. The
entire chimney, including the mo~t difficult third-
degree creosote deposit~, can then be ea~ily cleaned
u~ing standard methods.
The compo~ition~ of the invention have ths
advantages of having a water ba~e and containing no
volatile con~tituents. Con~equently, they are non-
flammable and nonvolatile and suitable for use around
heat or flames without danger of explosion or fire.
Becau~e they give off no harmful vapors, they can be
used safely in closed areas andjor at high temperatures.
In fact, the ~peed of the action of the compo~ition~ of
the pre~ent invention can be enhanced by rai~ing the
temperature of either the compo3ition, the environment,
or the 4urface being treated. In addition, the com-
positions are extremely stable, with an indicated shelf
life of in excess of two years.
The term~ and expressions which have been
employed in the foregoing specification are u~ed therein
as terms of de~cription and not of limitation, and there
i~ no intention in the uqe of quch terms and expres-
sion~, of excluding equivalents of the features shown
and de~cribed or portlon~ thereof, it being recognized
that the scope of the invention i~ defined and limited
25 only by the claims which follow.
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