Patented Aug. 24, 1943 2,327,701 UNITED STATES PATENT OFFICE 2,327,701 PANT AND WARNISH REMOVER COMPOSITION Carleton Ellis, Montclair, N. J., Carleton Ellis, Jr. and Bertram Ellis and Bank of Montclair, executors of said Carleton Ellis, deceased, as signors to Chadeloid Chemical Company, a cor poration of West Virginia, No Drawing. Application March 28, 1940, Serial No. 326,386 10 Claims. (C. 252-169) This invention relates to paint and varnish re the painted or varnished surface and effects movers, particularly to those in which the liquid Solution and/or disintegration of the coating vehicle is composed of one or more organic sol composition which afterwards can be easily re vents which volatilize or evaporate readily at moved in Some convenient manner. This re ordinary temperatures. This invention also in tardation of evaporation, of course, simultane volves the use of agents which exert a modifying Ously reduces any fire hazard which may be as action on such remover compositions. Sociated with the employment of paint and Paint and warnish removers for the most part Warnish removers. consist of volatile Solvents such as methyl Or I have observed that incorporation of certain ethyl alcohol, acetone or methylethyl ketone, Substituted paraffins, e. g., nitrated and halo ethyl acetate or other low-boiling esters, benzene genated paraffins, particularly those which are or toluene and the like. The term "ethyl ace Solid bodies at ordinary temperatures, either tate,' as used in the appended claims is in alone or as a substitute for part of the waxy ma tended to include other esters which have boil terials, results in decreased rate of evaporation ing points not substantially higher than 77° C. 5 of the Volatile liquid ingredients of remover com Either an individual liquid or a mixture of two positions. In this specification, the term "solid or more such liquids may be employed. In some Substituted paraffins' means any nitrated or instances it may be desirable to incorporate some halogenated paraffin or mixture of said nitrated higher-boiling liquid, such as tetrahydro and/or halogenated paraffin which is solid at naphthalene, the methyl or ethyl ether of glycol, 20 Ordinary temperatures. If a large proportion of or other similar fluid substances which also may Waxy materials is not detrimental to the pur exert a solvent or disintegrating action. On the pose for which the remover composition is to be paint or varnish film undergoing treatment. In applied, then solid substituted paraffins alone the above list of volatile solvents "ethyl acetate may form the evaporation retarding agent. On or other low-boiling esters' was intended to in 25 the other hand, if it is desirable that only a small clude such esters as have boiling points not con proportion of waxy bodies should be present in siderably higher than that of ethyl acetate. And the remover as evaporation retardants, then a in the appended claims, “ethyl acetate' is in mixture of paraffin wax (or other appropriate tended to embrace such equivalents. wax) and solid substituted paraffins may be em Such liquids, or mixtures thereof, when Spread 30 ployed. In most cases the proportion of solid or brushed on painted or varnished surfaces Substituted paraffins can be less than that of the although exerting a loosening or Solvent action WaX, or Waxes, employed. In other words, the nevertheless evaporate, for the most part, SO WaX may form a major portion of the mixture readily that the surface coatings are only in and the Solid substituted paraffins a minor pro completely disintegrated and therefore not easily portion. If desired, however, the proportion of removed by scraping gently with a knife blade, Solid Substituted paraffin hydrocarbons may be spatula, or other instrument, or in Some other greater than that of the waxy material. convenient manner. To overcome this feature I have observed also that when paraffin wax, of too rapid evaporation it is customary to in for example, is employed as the evaporation re corporate in such composition a retardant of 40 tardant in remover composition and evaporation evaporation. Examples of such retardants are of a Small proportion of the volatile liquid in paraffin wax, montan or ceresin Wax, crude scale gredients has occurred, then the main body of wax, beeswax and the like. Any one of these the renover composition becomes covered with waxy bodies or a mixture thereof may be em a thin layer of paraffin wax which greatly re ployed. Usually the percentage of incorporated 45 tards further evaporation of the liquid. This wax is relatively low, say 2 to 5 per cent. layer of Wax, however, appears to be crystalline When remover compositions containing such in character and brittle. Furthermore, when waxy bodies are spread or brushed on painted or viewed closely the wax film seems to contain varnished surfaces, then evaporation of a Small Small minute openings through which continued proportion of the volatile liquid (or admixed 50 evaporation of liquid slowly occurs. As the wax liquids) results in the formation of a thin coating film increases in thickness these openings may of Wax over the remover composition. This become larger and eventually actual breaks in coating of wax greatly reduces the rate of evapo the film Will be formed. ration of liquid from the removed composition. When solid substituted paraffins are incorpo The latter therefore remains in contact with 55 rated in paint and varnish removers containing 2 2,327,701 paraffin (or other) wax, or when such substi during the same time interval and the film of wax tuted paraffins are admixed with paraffin (or was translucent or crystalline in character. other) wax and the admixture incorporated into A substituted paraffin wax that is solid at or paint removers, then it has been observed that dinary room temperatures and suitable for use the wax film formed on the surface of a body in my invention may be made in the following of paint and varnish remover (when the latter manner. A Solid paraffin wax melting at about is exposed to the atmosphere) is much less brit 60 C. is treated with nitric acid at a temperature tle, less crystalline in character, and contains slightly above the melting point of the wax. If less small minute openings through which evapo desired a catalyst, such as aluminum nitrate may ration of liquid may occur. In other words, the 10 be used. After the reaction is completed, the paraffin (or other) Wax employed as an evapo Wax layer is separated from the acid layer. The ration retardant when used in conjunction with Waxy nitrated product is washed several times solid substituted paraffins yields a plasticized With hot water to remove any entrained acid or film in which the substituted paraffins are the catalyst. Unreacted paraffin wax may be sepa plasticizing agents. This unexpected plasticizing 15 rated by employing acetone or any other suitable action of solid substituted paraffins also forms a solvent in which the nitrated product is more part of my invention. It has been noted too, soluble than the unreacted portion of the wax. probably as a result of this plasticizing effect, A chlorinated paraffin suitable for use in my that a mixture of Solid substituted paraffins and invention may be made by the following method. wax exerts a greatly enhanced evaporation-re 20 A paraffin wax is heated above its melting point tarding action in paint and varnish renovers of and chlorine gas bubbled through the molten the volatile solvent type either wax or solid sub Wax. The composition of the product is con stituted paraffins alone, when present in the same trolled by stopping the chlorination when the proportion as the mixture of Wax and solid sub Weight of the paraffin wax has been increased by stitutel paraffins. 25 the proper amount. In some instances it is desirable that the vis Brominated or other halogenated solid paraf cosity of the paint and varnish remover be in fins suitable for use in this invention may be creased, thus preventing or substantially reduc made in any convenient suitable manner. It is ing its ready flow or easy spreading over the sur preferred, however, that the substituted paraffin face to which it is applied. Generally increased 30 be a solid at ordinary temperatures. In certain viscosity may be secured by dissolving a small cases, the product may be a liquid at ordinary proportion of a soluble cellulose compound (a temperatures. cellulose ether, e. g., methyl ethyl or benzyl cel Other compounds employed in conjunction lulose, or a Cellulose ester, Such as the nitrate or With the solid substituted paraffins are the same acetate) in the remover composition. I have as those commonly used in paint and warnish noted that in Such cases incorporation. Of Solid eroWes. substituted paraffins with the soluble cellulose My invention is applicable to any remover em derivatives in remover compositions containing ploying a waxy material as an evaporation re volatile solvents imparts to such compositions tardant. AS previously mentioned, I have ob evaporation-retarding properties greater than 40 Served that the substituted paraffin wax may be would be expected. This employment of solid used in part or wholly as a substitute for the wax Substituted paraffins in conjunction with soluble Ordinarily used. If a mixture of waxes is used cellulose derivatives is included in my invention. they may be admixed and dissolved in the liquid Furthermore, it has been observed that removers ingredients of the remover composition. In some containing both cellulose derivatives and solid cases the liquid ingredients may be heated and substituted paraffin bodies evaporate much more the Wax dissolved therein. When the latter slowly than When either the retardant or thick method is used enough wax is usually employed ener is used alone. - So that a precipitation of the wax occurs upon Substituted paraffin waxes being compatible cooling the Solution to room temperature. Any With most organic solvents can be used in many 50 method incorporating the various ingredients types of removers. I find that solvents such as may be used and the wax or waxes introduced benzene, acetone, methyl alcohol, methylene chlo Whenever Convenient, the essential point being ride, carbon tetrachloride, tetrahydro-naphtha that the finished product is saturated with at lene or ethyl acetate may be used as paint re least one of the wax constitutents. mover Solvents in conjunction with solid substi 55 As mentioned above, the removers may be com tuted paraffin as an evaporation retardant or pounded with a thickener such as a cellulose de With mixtures of a Solid substituted paraffin and rivative which helps retain the remover composi another Wax or other Waxes. Any mixture of the tion on vertical or slanting surfaces. Occasion above Solvents may be used but it is customary ally the removers are formulated to give a pasty to employ at least one liquid capable of repress 60 product by employing a large excess of wax. ing the solubility of the wax or waxes present. Whatever may be the case, a film must be formed When solvents such as methylene chloride, car to retard evaporation and I have found by ex bon, tetrachloride or ethylene chloride are used periment that a solid substituted paraffin im with the Solid substituted paraffins, non-inflam proves wax films by acting as a plasticizing agent mable paint and varnish removers may be made. 65 and in So doing consequently forms a tougher The So-called plasticizing ability of a solid sub and less pervious film that enhances retardation stituted paraffin is effective over long periods of Of evaporation. time. I have observed removers (containing in The following examples will illustrate my in part or in whole a substituted paraffin retard vention, though I do not wish to be limited to ant) that have been in contact with air in open 70 these examples, the specific compounds uSed, the evaporation dishes for as long as two weeks and quantities prescribed or the methods employed, the plasticizing effect of the substituted paraffin as all of these factors may be varied within wide still existed, and Very little of the solvent had limits. evaporated. A remover not containing the solid Eacample 1-A Solid nitrated paraffin body was substituted paraffin lost a majority of its solvent 75 made in the following manner. Ten parts of the w 2,827,701 3 wax were admixed with 12.2 parts of hydrated plasticizing effect of the nitrated hydrocarbons aluminum nitrate (Al (NO3)3.9H2O) as catalyst thus was demonstrated clearly. and 4.3 parts of nitric acid (sp. gr. 142) were Eacample 6-A remover was made containing added after heating the mixture to 100° C. The Only benzene as a solvent and the retardant com reaction mixture was maintained at 100° C. for posed of 4 per cent montan wax and 1 per cent 25 hours during which time it was stirred Wig nitrated paraffin wax. The film formed during orously and at intervals of 6 hours there were evaporation of the solvent was clear and retard added 4.3 parts, 4.3 parts and 2.1 parts, respec ed evaporation better than when montan wax tively, of nitric acid. At the end of the pre Was employed alone. viously mentioned total time (25 hours), the Waxy 0 Eacample 7.-A paint and varnish remover layer was separated from the aqueous layer. The (analogous to that described in Example 6) was nitrated wax was washed well with warm Water made by substituting ceresin wax for montan and then extracted with acetone. Any insolu Wax. The latter mixture exhibited properties ble matter was removed filtration and then the and comparisons much like those given for the acetone evaporated. The product, a concentrat 5 montan wax removers, ed nitrated paraffin, was Solid at room tempera Eacample 8-Two mixtures were made con ture. taining nitrocellulose. Acetone was used as a Eacample 2.-A paint and varnish remover was Solvent and 5 per cent nitrocellulose dissolved made of the following composition: therein. In one of the solutions 3 per cent (based Per cent 2) on Weight of solution) of a solid nitrated paraffin Acetone.------50 Was dissolved. The evaporation rate of the solu Methylene chloride------45 tion containing the wax was much slower than Nitrated paraffin Wax.------5 the straight nitrocellulose solution. Also, the Wax-cellulose derivative solution lost solvent The nitrated wax as made in Example I Was 2 more slowly than a corresponding wax solution dissolved in the acetone and the methylene chlo not containing a cellulose derivative. ride added. This remover had a low evapora Eacample 9.-Chlorinated paraffin wax was tion rate and efficiently removed various paints made by the following method. Paraffin wax and varnishes. melting at 50-55 C. was heated to 70° C. Chl Eacample 3.-A paint and warnish remover hav 3) rine gas was bubbled through the molten wax ing the following composition Was made: until the weight of the wax had increased to such Per cent a point that the chlorine content was 10 per cent Acetone ------47.5 of the product. Hydrogen chloride formed was Benzene ------47.5 removed by Washing the chlorinated wax with 35 Warm water. The temperature of the wash water Nitrated parafin Wax.------5 should be substantially above the melting point The solid nitrated paraffin as obtained in Ex of the chlorinated wax product. ample 1 was dissolved in the acetone and added Eacample 10-A paint and warnish remover to the benzene. When left in an evaporating Was made as follows. In a mixture of equal dish in contact with air the Wax formed a film 40 parts by weight of benzene and acetone, 5 per on the remover that was very impervious and cent by Weight of chlorinated wax, as made in retarded evaporation excellently. The film was Example 9, was dissolved. This composition re so transparent that it appeared non-existent un moved paint very Well. til the surface was touched and then a Wrinkling Eacample 11-A paint and varnish remover effect of the film was observed. was made in the following manner. The solvent Eacample 4-A remover containing 4 per cent Was Composed of equal weights of acetone and paraffin wax and 1 per cent nitrated paraffin benzene. Four per cent paraffin wax and 1 per wax in a solvent composed of equal parts of ace cent chlorinated wax, as made in Example 9, tone and benzene was made. The paraffin Wax were mixed with the solvent. The parafin wax was dissolved in the benzene and the nitrated 50 Was not completely soluble. This remover had paraffin in acetone and then the two Solutions properties similar to those of the remover in Ex mixed. The remover composition contained some ample 4. undissolved paraffin wax. The film on the evap Eacample 12-A non-inflammable paint and orating remover appeared to be more transpar Varnish remover is made in the following man ent than when only paraffin wax was used in the 55 ner. Nitrated paraffin wax, as made in Exam same mixed solvent. ple 1, is dissolved in a mixture of methylene Eacample 5.-A remover was compounded which chloride and carbon tetrachloride and tetrain is contained 4 per cent nitrated paraffin Wax (from added to the solution. The proportions of in Example 1) and 1 per cent paraffin Wax in a Sol gredients are as follows: vent consisting of equal volumes of acetone and 60 Parts benzene. The paraffin wax was dissolved in the Methylene chloride------55 benzene and the nitrated compound in acetOne. Carbon tetrachloride ------13 The two solutions were mixed and the resulting Tetrahydro-naphthalene.------27 product, when allowed to evaporate, produced Nitrated paraffin wax------5 a film that was very transparent. This remover 65 composition, when placed in an evaporating dish It is seen from the foregoing disclosures that and exposed to the atmosphere for two weeks lost my invention provides paint and varnish remov much less solvent than did the composition as ers that have an improved quality. It involves made in Example 4 under the same conditions. the use of solid substituted paraffins as retard Comparison of the waxy film in each instance in 70 ants of evaporation of the volatile components dicated that the latter composition (from EX of the removers. These substituted paraffins are ample 4) gave a thick, rough, crystalline film solids at ordinary temperatures and may be used which was not transparent and the film from alone or partly to replace waxes commonlv em the composition containing nitrated hydrocar ployed in paint removers as evaporation retard bons was tough, smooth and transparent. The 5 ants. In ordinary practice 1 to 5 per cent total 4. 2,327,701 waxes is enough to retard evaporation to the solvent selected from the group consisting of desired degree. These proportions are neither benzene, toluene, acetone, methyl ethyl ketone, the maximum nor minimum, as greater or lesser methylene chloride, ethylene chloride, carbon quantities of wax may be employed in Special tetrachloride, methyl alcohol, ethyl alcohol and caSeS. ethyl acetote; and a solid substituted paraffin The quality of the paint and varnish removers . selected from the group consisting of solid ni is improved when solid substituted paraffin hy trated paraffin Wax and solid halogenated paraffin drocarbons are incorporated therein. This in wax, solid nitrated Scale Wax, solid halogenated provement comprises decreasing the evaporation scale wax, solid nitrated Sweater oil, Solid halo rate of the removers and thereby allowing the O genated Sweater oil, Solid nitrated heavy Wiscous liquid ingredients more time to act on the surface liquid paraffin and Solid halogenated heavy vis to be cleaned. Furthermore, when Solid substi cous liquid paraffins, the proportion of said Solid tuted paraffins are present the film formed on substituted paraffin being not substantially less the surface of a remover composition (due to than 1% and being sufficient to form an evap partial evaporation of liquid ingredients therein) oration-retarding film on the surface of said is tougher, thinner, more transparent and less composition on exposure to the atmosphere, pervious than when waxes alone are used. Only Whereby further evaporation of the Volatile Sol small amounts of the solid Substituted paraffin vent is retarded. may be necessary to give an improved film when 2. A finish remover composition, substantially used in conjunction with other waxes. 20 devoid of Suspended inorganic Substances insol Although my invention has been illustrated uble therein, and adapted for softening old paint with paraffin wax and the nitration and chlo and varnish film preparatory to removal there rination thereof, I do not Wish to be limited to of, which remover comprises at least one volatile those particular paraffins or aliphatic hydrocar solvent selected from the group consisting of bons. Other materials which may Serve equally 25 benzene, toluene, acetone, methyl ethyl ketone, well include crude scale Wax, sweater oil, or even methylene chloride, ethylene chloride, Carbon high-boiling or heavy, viscous liquid paraffins tetrachloride, methyl alcohol, ethyl alcohol and which yield solid substituted derivatives. Such ethyl acetate; and a solid nitrated paraffin wax, substitutes for paraffin wax are, in all cases, hy the proportion of Said nitrated paraffin Wax be drocarbons which are either Solids at room tem 30 ing not substantially less than 1% and being perature or are viscous liquids at room temper sufficient to form an evaporation-retarding film ature, and they are all non-volatile, except at on the surface of said composition on exposure high temperature. Neither do I wish to be to the atmosphere, whereby further evaporation limited to those substituted paraffins which con of the volatile solventis retarded. tain only one Substitution group or radical, since 35 3. A finish remover composition substantially compounds containing One, two or three nitro devoid of suspended inorganic substances insol groups, or mixtures of Such compounds, are uble therein, and adapted for softening old paint equally applicable. What I do wish to avoid is and warnish film preparatory to removal thereof, the employment of those paraffinic or aliphatic which remover comprises at least one volatile hydrocarbons which possess such relatively low 40 Solvent Selected from the group consisting of ben molecular Weights that introduction of one or Zene, toluene, acetone, methyl ethyl ketone, meth more nitro groups per molecule (of hydrocarbon) ylene chloride, ethylene chloride, carbon tetra will give rise to the formation of an explosive chloride, methyl alcohol, ethyl alcohol and ethyl or otherwise unstable product. acetate; and a solid halogenated paraffin wax; The liquid ingredients or solvents which are the proportion of such halogenated paraffin wax Suitable for my purpose include those organic being not substantially less than 1%, and being compounds which are normally liquid at atmos Sufficient to form an evaporation-regarding film pheric pressure and ordinary or room tempera On the surface of said composition on exposure tures but which vaporize or evaporate readily at to the atmosphere, whereby further evaporation room temperature. By the term solvent I mean 50 Of the volatile solvent is retarded. not only an individual Substance but also a mix 4. A finish remover composition substantially ture of two or more liquids which are mutually devoid of suspended, inorganic substances in soluble one in the other and which do not inter Soluble therein and adapted for softening old act chemically when admixed. Preferably such paint and warnish films preparatory to their re liquids are anhydrous or substantially so, since moval, which remover contains a composite sol the presence of an appreciable proportion of vent which includes a volatile solvent selected water may prevent formation of a homogeneous from the group consisting of benzene, toluene, liquid phase or may exert some other undesir. acetone, methyl ethyl ketone, methylene chloride, able effect. ethylene chloride, carbon tetrachloride, ethyl In the foregoing specification where I have 60 alcohol, methyl alcohol and ethyl acetate; and used acetone it is understood that various ace Which Solvent also includes a higher-boiling sub tone substitutes, e. g., the product known as stance Selected from the group consisting of methyl acetone (i. e. methyl ethyl ketone), may tetrahydro-naphthalene and methyl and ethyl be used. When methyl acetone is mixed with ethers of glycol, said remover also containing a about an equal part of a good grade of benzene 65 Solid substituted paraffin selected from the group (benzol) the resulting mixture is slightly more consisting of Solid nitrated paraffin wax, solid active as a softening agent than acetone alone, halogenated paraffin wax, solid nitrated scale or acetone mixed with about an equal amount wax, Solid halogenated Scale wax, solid nitrated of benzol. Sweater oil, solid halogenated sweater oil, solid What I claim is: nitrated heavy viscous liquid paraffins, and solid 1. A finish remover composition, Substantially halogenated heavy viscous liquid paraffins, the devoid of suspended inorganic Substances insol proportions of said solid substituted paraffin be uble therein, and adapted for softening old paint fing not less than about 1% and being sufficient to and varnish film preparatory to removal thereof, form a film on the surface of said composition by which remover Comprises at least One volatile partial evaporation of Said volatile solvent from 2,827,701 5 Said composition on exposure to the atmosphere, solid substituted paraffin is not more than about whereby further evaporation of said volatile sol 5% and not less than about 1%. vent mixture is retarded. 7. A finish remover according to claim 5, in 5. A finish remover substantially devoid of sus which the proportion of said waxy body is in ex pended, inorganic Substances insoluble therein cess of that of solid substituted paraffin. and adapted for softening old paint and warnish 8. A finish remover according to claim 5, in films preparatory to their removal which com which the proportion of solid substituted paraffin prises a Solvent mixture which includes at least is in excess of that of said waxy body. one volatile solvent selected from the group con 9. A finish remover according to claim 1, also sisting of benzene, toluene, acetone, methyl ethyl Containing a cellulose thickening agent soluble ketone, methylene chloride, ethylene chloride, therein and selected from the group consisting of Carbon tetrachloride, methyl alcohol, ethyl alco Cellulose esters and cellulose ether. hol and ethyl acetate; and which solvent in 10. A finish remover composition adapted to cludes a higher boiling solvent selected from the soften old coats of paint and varnish preparatory group Consisting of tetrahydro-naphthalene and li to removal thereof, of the type containing a vola methyl and ethyl ethers of glycol, said remover tile organic liquid solvent for said old coats and COntaining also an admixture of a waxy body an evaporation retarding film forming wax, such Selected from the group consisting of paraffin composition being substantially devoid of sus wax, montan Wax, ceresin wax, crude scale wax pended inorganic Substances insoluble therein, and beeswax, together with a solid substituted 2) such composition containing a chemically un paraffin Selected from the group consisting of modified waxy body selected from the group con Solid nitrated paraffin wax, solid halogenated sisting of paraffin wax, montan wax, ceresin wax, paraffin wax, solid nitrated scale wax, solid halo crude scale wax and beeswax; and a solid sub genated scale wax, solid nitrated Sweater oil, solid stituted paraffin selected from the group consist halogenated sweater oil, Solid nitrated heavy 25 ing of Solid nitrated paraffin Wax, Solid halo Viscous liquid paraffins and Solid halogenated genated paraffin Wax, Solid nitrated Scale heavy viscous liquid paraffins, the total proportion wax, solid halogenated scale wax, solid nitrated of Said Waxy body and said Solid substituted par sweater oil, solid halogenated Sweater oil, affin being not less than about 1% but sufficient to solid nitrated heavy viscous liquid paraffins form a film on the surface of said composition by 3C) and Solid halogenated heavy viscous liquid par partial evaporation of solvent from said composi affins; the total combined amounts of Said tion on exposure to the atmosphere, whereby waxy body and said solid substituted paraffin be further evaporation of said solvent mixture from ing from 1% to 5% of said composition, and the Said composition is retarded, and the proportion amount of Said Solid substituted paraffin being of said Solid substituted paraffin being sufficient 3.: 3 enough to plasticize the said waxy body con to plasticize the Waxy body in the film formed on tained in the evaporation retarding film formed partial evaporation of solvent from said composi from a layer of Said remover composition when tion. applied to a surface from which the old coat is to 6. A finish remover according to claim 5, in be removed. which the total proportion of said waxy body and 40 CARLETON ELLIS.