CA1268691A - Coating remover and wood restorative compositions and methods of using same - Google Patents

Abstract

Abstract of the Disclosure Compositions and methods of using the same are disclosed, the compositions being effective for the removal of paints, stains, varnishes, resins, grease, wood pitch, urea and phenolic resins, creosote, and also as a wood restorative. The compositions consist essen-tially of an aqueous solution of an alkali metal hydrox-ide, sodium bicarbonate, ethylene glycol, glycerol, and xanthan gum. Enhanced effectiveness of the compositions is obtained in some cases by further application of a weakly acidic oxalic acid solution. The compositions are applied to the surface having the coating desired to be removed by brushing, spraying, and the like, allowed to stand for a time, then either wiped off or washed off with water, except in the case of creosote removal, where the composition is allowed to dry and then removed by conventional methods.

Description

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COATING REMOV~R AND WOOD RESTORATIVE COMPOSITIONS
AND METHODS OF USING SAME

Backqround of the Invention ........ ........._ . ~
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 ,''.7, 1 ~ ^ ~
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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 , ç'~
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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 - _.
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 ~2~

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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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 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 --1 0-- .

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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 , ~268G9i 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.

Claims (22)

What is Claimed is:

1. A nonflammable, biodegradable, non-herbicidal composition for the removal of oil- and water-based paints, stains, varnishes, and clear resins consisting essentially of an aqueous solution of the following components, by approximate weight: 5 to 15%
alkali metal hydroxide, 0.5% sodium bicarbonate, 0.1 to 5% ethylene glycol, 0.05 to 1% glycerol, and 0.2 to 3%
xanthan gum.

2. A surface wood restorative composition consisting essentially of an aqueous solution of the following components, by approximate weight: 1.5 to 5%
alkali metal hydroxide, 0.5% sodium bicarbonate, 0.1 to 5% ethylene glycol, 0.05 to 1% glycerol, and 0.2 to 3%
xanthan gum.

3. A composition for preparing the surface of old, weather-beaten or water-stained wood for a new finish, the composition consisting essentially of an aqueous solution of the following components, by approx-imate weight: 1.5 to 5% alkali metal hydroxide, 0.5%
sodium bicarbonate, 0.1 to 5% ethylene glycol, 0.05 to 1% glycerol, and 002 to 3% xanthan gum.

4. A grease and oil remover composition consisting essentially of an aqueous solution of the following components, by approximate weight: 5 to 15 alkali metal hydroxide, 0.5% sodium bicarbonate, 0.1 to 5% ethylene glycol, 0.05 to 1% glycerol, and 0.2 to 3%
xanthan gum.

5. A wood pitch and resin removal composi-tion consisting essentially of an aqueous solution of the following components, by approximate weight: 7 to 15% alkali metal hydroxide, 0.5% sodium bicarbonate, 0.1 to 5% ethylene glycol, 0.05 to 1% glycerol, and 0.2 to 3% xanthan gum.

6. A composition for cleaning and restoring paint applicators consisting essentially of an aqueous solution of the following components, by approximate weight: 5 to 15% alkali metal hydroxide, 0.5% sodium bicarbonate, 0.1 to 5% ethylene glycol, 0.05 to 1%
glycerol, and 0.2 to 3% xanthan gum.

7. A composition for etching aluminum and epoxy-coated surfaces to aid in preparing the surface for application of a new coating, the composition con-sisting essentially of an aqueous solution of the fol-lowing components, by approximate weight: 5 to 15%
alkali metal hydroxide, 0.5% sodium bicarbonate, 0.1 to 5% ethylene glycol, 0.05 to 1% glycerol, and 0.2 to 3 xanthan gum.

8. A composition for removing lime dust, asphalt, fungi, algae, moss, pulp mill black liquor, and resin glue, the composition consisting essentially of an aqueous solution of the following components by approxi-mate weight: 5 to 15% alkali metal hydroxide, 0.5%
sodium bicarbonate, 0.1 to 5% ethylene glycol, 0.05 to 1% glycerol, and 0.2 to 3% xanthan gum.

9. The composition of claim 1, 2 or 3, including a foaming agent.

10. A method of removing a coating selected from oil- and water-based paints, stains, varnishes, clear resins, and enamels from a surface comprising:
(a) applying to said surface a composition consisting essentially of an aqueous solution of the following components by approximate weight: 5 to 15% alkali metal hydroxide, 0.5% sodium bicarbonate, 0.1 to 5% ethylene glycol, 0.05 to 1%
glycerol, and 0.2 to 3% xanthan gum; and (b) removing said composition from said surface, together with said coating.

11. The method of claim 10, including the additional step of application of an aqueous solution of oxalic acid to said surface, said oxalic acid solution containing from about 2% to about 6% by weight oxalic acid.

12. A method of restoring old, weather-beaten or water-stained wood surfaces comprising:
(a) applying to said wood surface a composi-tion consisting essentially of an aqueous solution of the following components by approximate weight: 1.5 to 5% alkali metal hydroxide, 0.5% sodium bicarbonate, 0.1 to 5% ethylene glycol, 0005 to 1%
glycerol, and 0.2 to 3% xanthan gum, and (b) removing said composition from said wood surface by the application of water to said wood surface.

13. A method of preparing the surface of old, weather beaten or water-stained wood for a new finish, the method comprising:
(a) applying to said wood surface a com-position consisting essentially of an aqueous solution of the following com-ponents by approximate weight: 1.5 to 5% alkali metal hydroxide, 0.5% sodium bicarbonate, 0.1 to 5% ethylene glycol, 0.05 to 1% glycerol, and 1 to 5% xanthan gum, and (b) removing said composition from said wood surface.

14. The method of claim 12 or 13, including the additional steps of application of an aqueous solu-tion of oxalic acid, containing from about 2% to about 6% by weight oxalic acid, to said wood surface and remo-val of said oxalic acid solution by the application of water to said wood surface.

15. A method of removing a coating of grease and oil from a surface comprising:
(a) applying to said surface a composition consisting essentially of an aqueous solution of the following components by approximate weight: 5 to 15% alkali metal hydroxide, 0.5% sodium bicarbonate, 0.1 to 5% ethylene glycol, 0.05 to 1%
glycerol, and 0.2 to 3% xanthan gum; and (b) removing said composition from said surface, together with said coating.

16. A method of removing a coating of wood pitch and resin from a surface comprising:
(a) applying to said surface a composition consisting essentially of an aqueous solution of the following components by approximate weight: 7 to 15% alkali metal hydroxide, 0.5% sodium bicarbonate, 0.1 to 5% ethylene glycol, 0.05 to 1%
glycerol, and 0.2 to 3% xanthan gum: and (b) removing said composition from said surface, together with said coating.

17. The method of claim 15 or 16 wherein removal of said composition from said surface is accom-plished by the application of water to said surface.

18. A method of cleaning and restoring used paint applicators comprising contacting the used appli-cator with a composition consisting essentially of an aqueous solution of the following components by approxi-mate weight: 5 to 15% alkali metal hydroxide, 0.5%
sodium bicarbonate, 0.1 to 5% ethylene glycol, 0.05 to 1% glycerol, and 0.2 to 3% xanthan gum.

19. A method of removing creosote deposits from a surface comprising:
(a) applying to said surface a composition consisting essentially of an aqueous solution of the following components by approximate weight: 7 to 15% alkali metal hydroxide, 0.5% sodium bicarbonate, 0.1 to 5% ethylene glycol, 0.05 to 1 glycerol, and 0.2 to 3% xanthan gum:
(b) allowing said composition to dry; and (c) removing said composition from said surface, together with said deposits.

20. A method of removing lime-dust, asphalt, fungi, algae, moss, pulp mill black liquor, and resin glue from a surface comprising:
(a) applying to said surface a composition consisting essentially of 5 to 15% alkali metal hydroxide, 0.5% sodium bicarbonate, 0.1 to 5% ethylene glycol, 0.05 to 1.0%
glycerol, and 0.2 to 3% xanthan gum; and (b) removing said composition from said surface, together with said coating.

21. The composition of claim 4, 5 or 6, including a foaming agent.

22. The composition of claim 7 or 8, including a foaming agent.