Патент USA US2137995код для вставки
Patented Nov. 1938’v - 2,137,995, ' UNI-TED s'r-A'rss jliATENTp OFFICE 2,131,995 , ORGANIC‘ PRODUCT AND PROCESS OF: ' ‘ ' MAKING THE SAME ' Allen The D. Mantle Whipple, LampAlexandria, Company of Ind., America, aasignor Chi cago, I_ii.,'a corporation ofilllnois . No Drawing. Application November 30, 1931, Serial No. 578,191 , 3 Claims. (01. 134-69) , which requires the application of a less‘ number of coats to form a deposited ?lm of desired thick ness, than would otherwise be required. Wherever in this speci?cation, the terms cel 5 ing materials wherein these synthetic coating lulose nitrate, nitro-cellulose, and pyroxylin are compositions dissolved by, dispersed in, and com-' used, they should be construed as being synony , bined with cellulose esters, impart certain new mous. As a basis for illustrating the novelty and and useful characteristics to the lacquers and This invention relates to synthetic substances, coating and molding compositionalacquers and enamels, and ?lms and objects made therefrom, and particularly to lacquers, enamels, and mold enamels and molding compounds and to the m ?lms and objects made therefrom, all as more particularly hereinafter described. The invention has as an object, the produc tion of new synthetic substances of practically zero volatility at ordinary temperatures, which 15 in, and of themselves combine in a, single ma terial, many of the properties of resins, gums, and also solvent softeners of the class which have come to be known in the plastics and surface coating industry as plasticizers. 99 . Another object of the invention is the pro duction of synthetic lacquers and enamel com desirability of my invention, in so far as its abil ity to modify the properties of solutions of cellu- m lose esters and particularly cellulose nitrate is concerned, a shortnarration of the development , of the use of plasticizing and molding composi tions is given. _ _ ' ‘ Cellulose nitrate in solution in ether and al- 15 cohol, was used at an early date under the name - of collodion as a coating to form ‘a protective sheath over cuts and scratches. The ?lm puck ered and contracted on drying. For most pur poses, this property was undesirable by reason st of its contraction, and its tendency to peel 0d. ' Tov overcome this fault, various materials such as positions having the properties of ‘depositing vcamphor, Canada Balsam, and castor oil were ' ‘?lms and protective coatings possessing the . incorporated in the collodion, and the ?exible , characteristics of great transparency, in, clear collodion of the Pharmacopoeia resulted. % 291 coatings, of great adhesion to surfaces to be coat when cellulose nitrate solutions, also'known as ed, great fullness and body, great permanence of pyroxylin solutions, began to be‘ used for other lustre, great durability, great‘ resistance to the purposes, the same diillculty was encountered. 3 destructive in?uences of water, light, and weath er, great toughness and ?exibility, and of being non-shrinking, and after having been thorough ly dried, being very resistant to re-psolution and attack, even by the usual lacquer solvents; A further object of the invention is to provide 35 such compositions wherein the total content of solids exclusive of pigments, may be so increased by additions of the new synthetic substances herein described, as to give fullness to the ?lms deposited from lacquers when they have ‘been. 40 thinned down to a viscosity suitable for spraying or dipping (between 100 and 300 'centipois'es as The coating bridged away from irregularities of " r the coated surface, or was too brittle for use on supple material like leather, or could not endure’, the warping of woods to which it was applied. Plasticizers were essential to modify the proper- ties of- the cellulose nitrate. The literature of the pyroxylin industry is cumbered with literally ~35 hundreds of compounds that are considered ef ?cacious for that purpose. Of these, only a dozen or so are of any present practical importance. ‘ The early celluloid lacquers used the camphor present in celluloid as the plasticizer. It was in ‘40 a measure effective, but in time, they camphor measured by the Stormer viscometer at 28° (3.), volatilized and disappeared and the ?lm became without the necessity of resorting to the use of brittle. 45 those cellulose esters previously used for. this , I Various drying oils, such as linseed oil, have 45 purpose, which have certain speci?c low‘ viscose , been incorporated in ' pyroxylin solutions, but since these ‘materials absorb oxygen from the A further object of the invention ‘is to provide ' air, and polymerize to hard resinous bodies, their ity characteristics. Properly plasticized synthetic molding composi» incorporation in pyroxylin solutions which dry almost entirely by evaporation of solvents, was 59 5o tions. Other objects of my invention will be appar— eat as the following description proceeds. detrimental, ‘and'caused the ?lm to ‘become brit 'tle in a short time. p " , Non-drying oils gave better results, and castor oil may beused to illustrate this class of mate 55 “5?: as an ingredient for lacquers. ‘ i 1‘ or enamel having “fullness” is one rials. It is slowdrying, but has the undesirable “ Cellulose nitrate is a cellulose ester commonly 2 2,137,995 habit of making the ?lm too soft.if_.used in slight excess. Under the in?uence of moderate heating, it exudes from the coating and the ni tro-cellulosev ?lm becomes brittle. Triphenyl phosphate, tricresyl phosphate and dibutyl phthalate have all been considered use ful as plasticizers, and have been used as sub stitutes for camphor, but they all have de?nite rates of volatilization, and since pyroxylin ?lms 10 deposited with this class of’ plasticizers are plas tic only by reason-of being very concentrated solutions, it is evident that as soon as the solvent has volatilized, the original brittleness of the cel lulose nitrate asserts itself. 15 ' Practically all lacquers and enamels include certain amounts of resin. There are several ‘reasons for their inclusion therein. They in crease the solid content in, the lacquer and en amels, without raising the viscosity of the solu 20 tion as rapidly as would be the'case if cellulose nitrate alone were used to produce the solid con tent of the coating. A high total solids content gives fullness to the ?lm. Resins also enhance the gloss ‘of the ?lm deposited from cellulose nitrate lacquers. Resins also promote the ad hesion of the lacquer ?lms to surfaces. Resins are incorporated in lacquers and enamels for the further purpose of rendering the deposited coat— ings more or less resistant to water. Heretofore, 30 clear pyroxylin lacquers have found only lim ited application out of doors by reason of the _ fact that the short wave lengths of sunlight de strength and durability in the high-‘viscosity nitro-cotton. ‘ Certain ?elds of the surface coating industry have heretofore been largely beyond the reach of the lacquer and enamel‘ industry by reason 5 of the physical limitations of the lacquers and enamels of the prior-art. Some of these ?elds are house paints, railroad and steamship paints, household paints, varnishes, and enamels usual ly sold to householders in cans, and intended to 10 be applied to surfaces by means of a brush. There existed several obstacles to the success of those brushing lacquers. They had to possess. a ?owing quality that enabled the user to brush, cross brush, and lap without leaving ridges or . brush marks. ' By the use of alcohols, such as ansol, and .hexalin, together with higher esters such as butyl propionate, combined with low viscosity pyroxylin, and‘the old plasticizers of the prior 20 art, lacquers have been produced that could be reasonably well applied by means of brushing. These prior-art brushing lacquers and- en amels, however, possessed several faults that have limited their use, although they have been 25 applied to small work such as shelves, chairs, 'and toys with fairly satisfactory results. The lack of ability of these lacquers and enamels of the prior-art to withstand the destructive ef fects of sunlight and the weather, and the fur 30 ther facts that in multiple-coat-work, the ?rst and succeeding coats were not inert to the sol stroy the-?lms too quickly by_brin_ging about the types of failure known as chalking, alligatorlng, the degraded cellulose of the low-viscosity nitro amels of the prior-art. depend upon the inclu cotton did not provide the wear resistance de 35 sired, nor the ability to resist those types of 35 checking or peeling. Pigmented lacquers or en sion of ?nely-divided ‘pigments to protect the film from the destructive e?‘ects of light by ab sorbing the harmful rays of short wave length. In the manufacture of nitro-cellulose lacquers and enamels, prior to the discovery of such low . viscosity nitro-cellulose as that described by‘ vents contained in the following coats, and that failure of surface coatings known as chalking, alligatoring, and loss of lustre, prevented these prior-art lacquers and enamels from realizing the full scope of useful application that their quick drying qualities would otherwise have made 40 possible. several inventors, it was not practicable to make _ The desideratum, therefore, has been the dis solutions having a nitro-cellulose content, which, covery of a means whereby spraying and dipping after thinning to the extent required for use as 'a dipping or spraying lacquer, namely, 100 to lacquers and enamels containing the strong, tough, and relatively stable high viscosity nitro cotton, and retaining all of the good properties 300 centipoises as measured by the Stormer viscometer at 28° 0., was of more than about’ 6%, since with ordinary nitro-cellulose, more 50 than this proportion rendered the solution too .55 ‘ 45 enumerated elsewhere in this speci?cation, can be manufactured. ' ' Cellulose esters, and particularly cellulose viscous. Moreover, in the presence of this maxi - nitrates, are subject to continued polymerization mum‘ amount of nitro-cellulose, the proportion after manufacture. They slowly and spontane of the gum used to promote gloss and adhesion, ously change their physical properties with time. had to be comparatively low, so that, as a rule, Amongst the properties which change, is solu > ‘it was necessary to limit the total solids content bility. of these old lacquers and enamels exclusive of Plasticizers of the prior-art may be divided pigment when thinned’ to spraying “viscosity, into three classes. namely, 100 to 300 centipoises as described above, (11) Those, like camphor, triphenyl phosphate and tricresyl phosphate, which possesses some to‘With less than the 13%. advent of the low-viscosity cotton, described by Pitman, and others, it became pos sible to increase the total solids content of lacquer and enamels, exclusive of pigments, I solvent properties for nitro-cellulose before it has polymerized to such an extent as to be no longer soluble. These plasticizers have slow rates of evaporation, and are fugitive con stituentsf-of the lacquers, enamels and mold ing compounds in which they are incorpo 65 rated. _ , tained oxy-cellulose, and hydro-cellulose, and (b) Those known as drying oils, like linseed oil, which have'no solvent properties for cellulose their nitrates in high percentage. As a con 70 sequence, they were unstable, and of poor tensile , esters, but which gradually take up and com bine with oxygen from the air, and in so strength. The conditions under which low doing, resinify. Invtime, the ?lms deposited viscosity cotton- is made, favor the breaking down from lacquers and enamels plasticized with of the cellulose molecule and the degradation this class of materials, become hard and brit of ' the cellulose, and lead to a general conces tle, and in consequence, of little protective sion by the lacquer trade that there is greater v?lue. ' to amarked degree, but in so .doing, the ability to increase the gum contents was not materially increased. Also, the low viscosity cotton, con 2,187,995 3.’ _ and permanently-plastic material, is a (c) Those materials which maybe represented - adhesive sticky semi-solid, which, at ordinary tempera- ‘ by eastor oil, and which are known as non tures,.will slowly ?ow. It has no boiling point .drying oils. These, like class (D) have no sol vent properties for-cellulose esters. They are and is'st'able up to the point at which chemical dissociation begins. Itis insoluble in petroleum capable of being colloidally dispersed in solu tions of cellulose esters by reason of their being miscible with the solvents of lacquer and enamel, and, by their presence among and between the particles of cellulose ester, lu 10 .15 or coal tar distillates or other hydrocarbons.‘ This material may be regarded as a solvent sof tener for nitro-cellulose or nitro-cellulose may be regarded as a solvent hardener for this new synthetic material. By putting this new syn into solution along with nitroé bricate, and'seem to soften the films deposited from lacquers and enamels in which they are incorporated, so long as enough solvent _re mains to keep them dispersed. When the true solvents, all of which are fugitive, have , thetic material cellulose, a molecular dispersion of one in the other throughout the mass is e?ectuated, and, if the volatile solvents should disappear from the lacquer, enamel or molding compound, there will remain a composite, non-volatile, perms-4 disappeared, these non-adhesive plasticizers are squeezed out by the contraction of the unplasticized ?lm, and exude so that they may be wiped from the surface. Heat rapidly ex nently-cohesive, and adhesive .and permanently plastic film, or object, that is-incapable of the disintegration which causes chalking, alligator pels the true solvents,‘ and. therefore, hastens 20 the "exudation of the non-drying oils. ing, etc. This ' , - 20 I That this new synthetic‘ resinous plasticizer method of forcing out these materials is so I desirably promotes the rapid polymerization of well recognized in the lacquer and enamel in- . nitro-cellulose to its di?lcultly-soluble, or insolu dustry, that a technical term has 'been applied to it. It is known as lwsteresis. ble state, in heretoforegknown solvents, although ' Of these ‘three cl of plasticizers, class a has been most useful. The lacquer or. enamel after losing its more highly volatile constituents, ‘ it is readily soluble and remains dissolved in my 25; retains the slowly-volatile solvents for a time,‘ and, therefore,,the solute remains inv a state of partial solution as long as some of the solvents remain or retain their solvent properties, oras long as the cellulose ester remains soluble. This distinction between the retention of the solvents ‘and the solubility of the celluloseester, depends upon the fact that cellulose, when nitrated, is new resinous plasticizer, is‘ indicated by the fact that, as shown by tests, ?lms deposited from lac quers compounded of nitro-ceilulose and this new ' resinous plasticizer are, after drying, completely inert to the solvents contained in succeeding 30 coats, and that coatings of steel panels so lac quered and enameled and prepared for weath erometer tests, have failed to be dissolved when soaked for a week in acetone, which is a power ful solvent for nitro-cellulose. ' ' 35 ‘This property, whereby a deposited and dried as pointed out above, subject to continued poly film of lacquer or enamel containing nitro-cellu merization and, as the polymerization proceeds, lose and this-new synthetic resinous plastieizer becomes less and less soluble in any heretofore is inert to the solvents of ‘succeeding coats, ren known solvent,‘ whereas, unpolymerized and poly 1181's such lacquers and enamels, when properly 40 are both soluble in the compounded to give flow characteristics during . merized nitro'cellulose _ new plasticizer herein disclosed. It, therefore, application, suitable for use as brushing lacquers. appears that lacquers or enamels or molding An example of such a brushing lacquer will compounds, plasticized ‘by the old methods, re be given later in this speci?cation. > main plastic for so long a time only as the nitro Tests have shown that ?lm's, deposited from ‘cellulose remains in "solution in the slowly lacquers and enamels containing acetyl cellulose vBlatile solvents, and that as soon as the solvents and this non-volatile; water-resistant, perma ' disappear,-- which they do in time, or as soon as nently-cohesive and adhesive and permanently plastic synthetic resinous plasticizer, are satis the nitro-cellulose becomes insoluble in those solvents, it passes out of solution, and the lac factorily plasticized, although it has not been 60 quers deteriorate with the production of the‘ ‘noted that appreciable solution of acetyl cellulose faults knownas chalking, alligatoring,.etc. in this new resinous plasticizer, occurs. How Furthermo . the adhesion of such lacquers ever, it has been found that by putting this non as have existed in the past, depends upon the volatile, water-resistant, permanently cohesive stlckiness‘of such giim's and resins asv are in and adhesive, and permanently-plastic material 55 55 troduced in order to eiihance the adhesion of the lacquers to surfaces coated with them. ' - into solution containing as its solute, acetyl cel lulose, or any hard ?lm-forming substance with In contradistinction to the .old and above de which it is compatible-and which is soluble in scribed method of plasticizing, the new method. the same solvents that dissolve this'new resin: herein revealed, consists in the oduction of a ,ous plasticizer, a molecular dispersionof the 60 into the sub plasticizer- which when introdu plasticizer throughout the mass is e?ectuated, stance to be plasticiaed, .. ‘_ the properties and that if the volatile solvents should disappear of a gum or resin, and is a_ strictly non-volatile. from ‘the lacquer or enamel or molding compo non-oxidizable, water-resisting, permanently sition, there willremain an intermolecular film plastic and permanently-cohesive and adhesive or cement, which, by reason of itsladhesiveness, Yes synthetic resinous material. ' . not only will bind together the associated mole Thisi'ion-volatile, water-resistant, permanent ly-coheslve and adhesive, and permanently-plas tic material is soluble in usual solvents for nitro cellulose, and is, itself, a solvent for nitro-eellu lose, and further --~_--~ ; the property of rap Wh promoting the polymerization of nitro-cellu Y! to the point at'which it‘ becomes insoluble other solvents for nitro-cellulose, but remains It “is in the new material. - - ‘his nm-vola?lt. permanently-cohesive and cules of the acetyl cellulose, but will also cement the entire mass to the surface upon which the lacquer or enamel ‘has been applied, with the I result that, no matter how polymerization of the acetyl cellulose may subsequently- proceed, and no matter how hard andhorny the acetyl cellulose may become, when considered in'its state of molecular division,.its particles are still bound together by a permanently-plastic, pliable, 2,187,995 adhesive material which, because of its complete lack of volatility, and its permanent adhesive ness, remains permanently in place upon and in sures an extremely long life to the lacquered or enameled surface, thus completely preventing the disintegrations which are known as chalking, alligatoring, etc. It will beapp'arent from the foregoing descrip tion, that this non-volatile, water-resistant, per 10 manently cohesive and adhesive and permanent ly plastic material will act as an efficient and desirable binder for the segregated molecular or colloidal particles, of any coating material, lac quer, enamel or molding compound, to which '15 particles it will permanently adhere. ‘ > It will also be apparent from the‘ foregoin coating, lacquers, enamel or molding compound and are therefore fugitive. The process of plasticizing herein described is of importance to the lacquer industry in that it provides, in one lacquer, the properties required for a “primer” coat, that is, the ?rst coat applied for the purpose of obtaining adhesion to the object or surface being lacquered, and at the same time provides a ?nishing coat by producing a. superior gloss and producing within the lacquer the ability 10 to permanently resist the effects of ageing that have heretofore so quickly destroyed lacquered surfaces. General experience in the surface-coating in dustries, has shown that organic surface coatings exposed to the weather, and particularly to sun light, deteriorate rapidly. and tests, conducted to disclose the reasons therefor, have established that this resinous plasticizer herein described is a non-fugitive component of coating materials, lacquers, enamels, and molding compounds in which it may be effectively incorporated, and, as ‘ the fact that the short wave-length radiations in the ultra-violet end of the spectrum of sunlight, 20 such, permanently conserves the essential prop are the principal cause of the deteriorations noted. erties of those substances; whereas, coating ma terials, lacquers, enamels and molding com - pounds, as now made, initially include substances such as cellulose esters which are bound together by other substances, which other substances in time fail to effectuate the binding of said par ticles, either because they evaporate, or because of some alteration in the solute, regardless of 80 whether it is intro-cellulose or some other sub-' stance. The new resinous plasticizer is, therefore, one which, in and of itself, is stable, is non-volatile, and is permanently adherent to other constitu ents of any coating material, lacquer, enamel or molding compound, whatever they may be, Much work has been done along that line of in vestigation, and it is generally conceded that no organic coating, whether it be oil and resin varnish or a pyroxylin lacquer or enamel, is proof 25 against the destructive in?uence of the short wave-length radiations, unless it be so thoroughly pigmented that the solid pigment particles will absorb and prevent the passage of these short wave-length radiations into and through the coat 30' ing or ?lm. However, no radiations having a wave length longer than 315 millimicrons, are 'known to have a destructive in?uence -on surface ‘ coatings. Tests,‘conducted to determine the light transmission characteristics of my new synthetic 35 in which it-may be effectively incorporated. It _ resinous plasticizer, reveal the fact that while this material is highly transparent to the light radia is therefore evident that the longevity of a lac quer or varnish is entirely dependent upon the tions in the visible range, and, therefore, can be used to make so-‘called water-white clear lacquers, character of its plasticizer, and that the deterio rations of these substances, as heretofore pro ' it is opaque to all radiations having a wave length shorter than 317_ millimicrons. "The practical as duced, is chie?y due to the elimination, the in pect of this property of the new resinous plasti activity or the lack of stability of their plastic cizer, is that clear lacquers may now'be manu Lacquered panels, exposed for breakdown tests factured with my invention, which, when exposed to the weather and sunlight, are more fully pro 45 in a weatherometer, have demonstrated the lon gevity of lacquers compounded with ‘the new tected against the , destructive .effects of short plasticizer, herein described, as compared with wave-length radiations than were the lacquers of the prior art when pigmented. . commercial lacquers compounded with plastic Other tests have shown that ?lms of applicant's izers such as castor oil, triphenyl phosphate, tri resinous plasticizer having a thickness of one cresyl phosphate, and dibutyl phthalate. 50 These tests have shown that, whereasthe best millimeter will pass 70% of spectral emanations obtainable commercial lacquers compounded with of a wave length of 400 millimicrons; but, if the fugitive plasticizers were completely destroyed substances from which said resinous plasticizer is 55 in from 250 to 300 hours’ exposureiin‘the weath produced ‘should contain contaminations of vari erometer, those lacquers that were compounded ous kinds, or are, otherwise, variable, the per 55 centage of transmitted spectral emanations will with the plasticizer herein described as’ non volatile and non-fugitive suffered no detectable vary, and, in some instances‘, maybe as low as . = . 2 change after 718 hours of exposure, under the 49%. 60 same conditions, even though the effort to de Test conducted in a weatherometer, in which izers. . . . tect a change was conducted with the aid of a powerful microscope. ' , . The product, thus produced, is a permanently plastic and non-brittle semi-?uid resin that is suitable for use in coating materials, lacquers, ' enamels and molding compounds, and capable of imparting desirable plastic properties thereto. It differs from ?uent substances such as castor oil, which, blended with coating materials, lacquers, 70 enamel and molding compounds, merely acts as a non-adhesive lubricant for the other constitu ents and readily exudes therefrom by hysteresis. It differs from‘such substances‘ as camphor, tri phenyl phosphate, vtricresyl phosphate and di u butyl: phtalate which in time disappear from the > coated panels are subjected to as close an ap 60 proach to sunlight as can at present be achieved arti?cially, and including a larger percentage of short-wave radiations than does sunlight, even on high mountains, alternated with high and ‘low temperatures and rain, have shown that lacquers 65 manufactured according to my invention, have produced coatings which indicate that they resist these destructive agencies over three times as long as the best commercial lacquers of the prior art. These new lacquers and enamels can, there— fore, bevsuccessfully used for coating objects sub 70 jected to outdoor exposure. Furthermore, these coatings are unaffected by grease, oil, gasoline, benzol, toluol, naphtha, or petroleum. ' ' I have made ?lms composed of nitrocellulose‘ and 2,187,996 As the acid number is reduced, the freezing. synthetic resinous plasticlzer. Such ?lms point of the synthetic resinous plasticizer is properties that excel the properties of - exhibit - celluloid. They may be made transparent. They may be colored as desired. They may have pig- I - , ments incorporated in them to render them opaque. , Such films are elastic, ?exible, odorless, = of great tensile strength and maybe raised. That is to say, at any given temperature, resins of this series'having higher acid ‘numbers ‘ l ' will be more liquid or plastic than those resins of lower acid numbers. It will, therefore, be seen that; where lacquers or enamels are to be sub jected to very low temperatures, use may advan tangeously be made of resins having acid num-. -, 10 bers higher than 24. folded and unfolded without cracking or suffering ' any apparent damage. vThey may be molded ac-' 10 cording to the well-known methods used for mold _The condensation and ‘polymerization- above ing celluloid. Because of the permanence of this plasticizer, outlined are preferably e?ectuated'by me in alue minum vessels, although vessels made of 'other these ?lms will retain these properties for an in materials which will not be attacked by the‘ in"- .- de?nite length of time. to describe in detail the ‘ .gr'edients may be employed. I shall now proceed ll Small batches of. material may be condensed manufacture of my new synthetic substance and and without the necessity of con give examples of its use in lacquers, enamels and stantpolymerized agitation, although it is my practice ‘to thor molding materials. ' It is to be understood that the oughly and continuously agitate. the ,material ' examples given are illustrative of my invention, during the entire'period of heating. 20 which, of course, is not limited thereto, since _ The product resulting from the condensation . many changes may be made therein without de and polymerization of phthalic anhydride and parting from the spirit and scope ofv the inven- I diethylene glycol, if producedas above described, tion. and __without other attention or modification, will The process of manufacturing this non-vola produce a‘ synthetic resin havingv the plasticizing tile, water-resistant, permanently-cohesive and 25 properties above described, but, by reason of the adhesive and permanently-plastic synthetic mate heat required for polymerization producing sis multaneously objectionable discoloring dissocia rial, may be carried into effect by subjecting a mixture in substantially the proportion of one molecule each of diethylene glycol‘ and phthalic. tion compounds, it will be of dark color and, so ‘far as visual inspection of the sticky mass sofpro 30 anhydride, to_a temperature of from 110 to ‘150 ‘ duced is concerned, it will be unattractive to one degrees centrigrade, but preferably 130_degrees not aware of its extraordinary usefulness as a centigrade, and continuing the heating and con plasticizer, and even to one conversant with-its sequent condensation and polymerization until. the desired product has an acid number between plasticizing properties, the dark color is likely 112 and zero, but preferably just below 24'. > It is to be understood that during the heatiniL. condensation and polymerization of- the above mixture, the‘ acid number gradually reduces from to create the belief that it will ‘be objectionable as a material to be used in the manufacture of clear water-white lacquers and in the manufacture of white pigmented lacquers, by reason of the pres ence of the objectionable coloring compounds above 180 to zero, depending upon the length or as above‘ described. duration of the continuation of the heating.‘ At - formed , I discovered that the inclusion of ray-control ?rst, that is, in the very early stages of the con densation, the ingredients seem. to be in solution ling substances, the principles of the effects of in each other, ‘but the solution is water-soluble. ' which are fully set forth in'myco-pending patent As the condensation followed by polymerlza- - application ?led‘ August 20, 1931, Serial No. 558, 329, was e?ective in preventing the formationof _-tion,'proceeds, ‘the solution becomes water-inét undesirable color characteristics during the con soluble, at an acid number of‘ approximately 112. At that time, it isv a liquid resin, and greater dens'ation and polymerization of this resinous and that the much-desired light color ‘quantities of cellulose ester are required to harden plasticizer, of 'the resin and its transparency in the visible‘ ‘ it, andovercome itstackiness, than would ‘be re— range could-be so produced. ' I‘ prefer, therefore, quired if the polymerization had proceeded to. still 50 when making this plasticizer, to‘ include in the As an opposite ‘extreme, the. lower acid numbers. solution polymerized to an acid number of zero, batch at the time of beginningthe heating, a ray- ' :is a plastic solid ‘at‘normal temperatures, and controlling substance‘v as described inthe above requires comparatively little cellulose ester to cited co-pending application, and speci?cally in _ ‘this case I prefer touse .0005 per cent-of copper . overcome its tackiness, and produce satisfactory - coatings, him and objects. It willbe seen, there fore, that between the acid numbers of 112‘ and zero, thereis agradual transition in the stateof being of the condensed and polymerized material, and it may therefore be said that an in?nitenum; ‘to ber of plastic resins exist in the above-indicated range. ’ All of them are useful, and are comprised nitrate. - . Throughout this specification emphasishasbeen the fact that nitrocellulose of high viscosity characteristics is entirely suitable‘for the manufacture of’lacquers and-enamels having a high total solids content, providing this .res-_ - placed upon ‘inous plasticizer be employed in sufficient quan- - - tity to provide the body characteristics in the fer to stop transition ‘at an’ acid number slightly , lacquer without unduly raising the viscosity of ‘ ‘_> below 24,‘ because of the fact that the plastic the lacquer. properties of the synthetic resinous plastlciz'er, as - It is not intended to‘ disclaim the use of nitro cellulose havingv low viscosity, characteristics, such ‘ above made, and stopped at an acid number just 'as that produced by Pitmanand others, because 7 below it, are such as to give excellent results with such low-viscosity nitrocellulose is satisfactorily within the scope of this invention, although I pre nitrocellulose of high viscosity characteristics. otherv cellulose esters, and other hard ?im "W' substances capable‘ of being plasticized , jzyatheticresinous plasticizers of thistype, rm ‘ plasticized by my new_ resinous material, and by 70 its use lacquers having suitable viscosity for spraying and dipping may be produced. Such made with the low-viscosity nitrocellu 18y well require that the transitlon'be . lacquers l'os'e can be notably improved beyond the limits oftbcpriorartbybeinlsimatotalsolibconr ' flav‘uatotheracidnumbei'stl'lanthatwhich];v I! c- . 6 2,187,995 tent and consequent fullness far greater than ever before possible. . ‘ ' ing and employing my invention, the following is cited: > Solids . ' ethyl lactate, H. I. F. naphtha, amyl acetate and ethyl oxy-butyrate. As an example of a lacquer suitable for spray Ounces Dry weight R. S. nitrocellulose, 60 to 80' Add half of the above mixture to the wetted nitrocellulose and mix thoroughly until the nitro-Y cellulose is completely dissolved. batch. seconds viscosity ____ ___ _______________ __ 3 10 My resinous plasticizer_________________ __ 20% Solvent Mixture _ As another example of a brushing lacquer, the ' following is presented: Solids Toluol 50 Denatured ethyl alcohol, 188 proof______ __ 15 Ounces Dry weight R. S. nitrocellulose of 20 to 30 20 My resinous plasticizer_________________ _.. 20% 5 Solvent Mixture Same as ?rst example of-brushing lacquer. 15 Ethyl acetate (85 to 88% ester and balance seconds viscosity_____________________ .._' 4% ethyl alcohol) _______________________ __ Amyl acetate 15 Ethyl lactate ‘ Mono ethyl ether of ethylene glycol____'___ 20 Butyl mono ethyl ether of ethylene glycol.._ 3 Procedure Dissolve the resin in the ethyl acetate. Wet the nitrocellulose with the toluol and the denatured alcohol. _ . Mix the amyl acetate, ethyl lactate, mono ethyl ether of ethylene glycol and butyl mono ethyl ether of ethylene glycol. Add half of the above mixture to the wet nitro cellulose and mix thoroughly. Add the solution of resin and the remaining As another example of spraying lacquer, I may . ' a seconds viscosity____ _‘_ _____ .._'_..___x____ 4% My resinous plasticizer_________________ __ 20% Solvent mixture and procedure _ Ounces seconds vviscosity _____________________ __ 3 My resinous plasticizer_________________ .._ 20% Solvent Mixture ' . Denatured ethyl alcohol, 188 proof______ .._ 15 Mono ethyl ether of ethylene glycol _____ __ . 32 J 8 E71. F. naphtha (H. I. F. means high ?ash ' ' Amyl acetate 10 _ 15 Ethyl oxy-butyrate_____________________ __ 5o Ethyl acetate contrast to'the practice of the prior art, my new resinous plasticizer may be incorporated in lac quers and enamels in such manner that the cellu lose ester constitutes less than 50% of the-total solids, other than pigment, and that said new 40 ‘ ' The reason for this remarkable improvement, is I , . point) 25% of the total solids, the resulting ?lms lacked 1 and still produce lacquers having great cohesive Dry weight R. S. nitrocellulose of 60 to 80 ' ' solids; that, if the resin or gum, which was the 31) weakest component of any prior-art lacquer, be included in the lacquer to an extent greater than ness. Solids Ethyl lactate be so proportioned that the cellulose ester con total solids, and, in some cases, as much as 87%, ‘ .Zylol It will be noted,_from the illustrative formulae given above, that my new resinous plasticizer reverses the practice of the prior art in the fol lowing manner. In the prior art, it was found that the production of useful lacquers required that the total solids, other than pigment, should plasticizer constitutes more than 50% of the said Same as in the ?rst example above given. As an example of a brushing lacquer, the fol - 20 ‘ or gum made this defect more prominent; but, in Ounces Dry weight R. S. nitrocellulose of 20 to 30 lowing is presented: ‘ coherency, and that the further increase of resin ' Solids ‘1' Procedure Same as in previous examples. stituted 50% or more than 50% of such total glixcii solvent and thoroughly mix the entire at . use: 5 Add the solution of the resin and the remain ing mixed solvent and thoroughly mix the entire 8 10 Procedure Dissolve the resin in the ethyl acetate. Wet the nitrocellulose with the zylol and the ' g5 denatured jalcohol. Mix the mono ethyl ether of ethylene glycol, that small quantities of high-viscosity cellulose esters act effectively to so harden my new plas ticizer that it constitutes the major coherent and adhesive portion of the total solids of the lacquer. Having thus described my invention, what I 50' claim is: l. The process of producing a resinous plas ticizer, which consists in subjecting phthalic an hydride and diethylene glycol to a temperature of approximately 130 degrees centigrade until a de ' sired condensation product is produced. 2. An organic nitro~ce1lulose coating material including, as a component, a plasticizer which is the polymer of diethylene glycol and phthalic an hydride produced at a temperature approximat ing 130 degrees centigrade. 3. A fusible, water~resistant phthalic anhy dride-diethylene glycol resin condensed and poly merized at a temperature approximating 130° C. and having an acid number between 112 and 0. ' ALLEN D. WHIPPLE.