US2608493A - Synthetic waxes - Google Patents

Description

Patented Aug. 26, i952 2,608,493 SYNTHETIC WAXES Joseph Cunder, East Orange, and Francis J. Licata, West Caldwell, N. J., as'signors to Nopco Chemical Company, Harrison, N. J a corporation of New Jersey No Drawing. Application June 30, 1948,

Serial No. 36,258

.This invention relates to new and improved synthetic waxes and more particularly to new synthetic waxes producedfrom fatty materials andmetallic soaps.

.Waxes such. as carnauba, montan, beeswax,

candelilla, paraffin, etc., have been used for many years-for a wide variety of coating applications.

Numerous synthetic products have been proposed to take the place of many of these natural waxes eitherbecause of the relatively high cost of the natural products, their lack of availability, or Various characteristics which rendered the natural waxes somewhat unsatisfactory for the uses contemplated. Although some ofthese synthetic waxes have constituted an improvement over the natural products in certain respects, there is still a. considerable demand for inexpensive, improved synthetic materials which mayxbeemployed in place of the natural waxes. This is particularly true-in the case ofcarnauba wax for which a synthetic substitute is highly desirable. Carnauba' wax is one of the most satisfactory of the natural waxes particularly in regard to the properties of melting point, water resistance, and solvent resistance. However, this natural product is somewhat expensive, and at the present timeit' is'alsorelatively unavailable. Furthermore carnauba wax, as with all natural waxes, is subject tovariations inquality in contrast to the uniformity which may be obtained in a synthetic product i It is the object of this invention to provide improvedsynthetic waxes.

f A furtherobject of the invention is to provide a synthetic wax substitute for carnauba wax.

Claims. (Cl. 106-243) Other objects of the invention will in part be:

obviousand will in part appear hereinafter.

We have foundthat the above and other objects of' the invention may be accomplished by blending a eutectic mixture of metallicisoaps with a fatty material which is'normally solid at room temperature. 7 V

" The term fatty material as employed in the specification and claims connotes a material which" has a fatty alcohol or a long chain fatty acid or somewhat similar acid such as abietic acid as a principal, constituent. Thus, thephrase fatty materials which are normally solid at room temperature includes natural fats which are solid at room temperature, e. g. palm oil, etc., hydrogenated fats and oils, the saturated fatty acids having ten or more, carbon atoms, thesaturated fatty alcohols containing twelve or more carbon, atoms;and normally solid waxy materials colltaimng may. acidsorgsomewhat; similaracids such as abietlc acid in the free or combined state," e. g. rosin, hydrogenated, rosin, etc. Ordinarily it is preferred to employ hydrogenated fats and oils, and particularly hydrogenated fish oils; e. ig. hydrogenated sardine oil, as the fatty material in preparing the products of the invention. These materials are preferred because of theirrea'dy availability, low cost, and the excellenc'eflofthd products produced therefrom. The other fattyj materialsmentioned above will, however, give exit cellent products, and in some cases whensyn thetie waxes of a pmticular nature are'desirefd, it may be preferable to use a fatty material otherv than one of the hydrogenated oils. For example,

by employing some of the shorter chain fatty acids as the solid fatty material, synthetic ,waxe'si having a relatively low melting point may. be obtained; and conversely by employing tlievieiy long. chain fatty acids, products having high melting point may be obtained.

. The well-known Hackhs Chemical Dictionary}; third edition, states that a eutectic mixture-lea; mixture of two or more substances which. has the, lowest constant melting point of any mixtureof its constituents. Probably the most common" eutectic mixtures are thosehaving only two, components, and insofar as it is practical the eutectic mixtures used in the present invention are of that Thus it is preferred to employ eutectic,

mixtures of metallic soaps containingonly two different metallic soaps. As is Well knownyhovv ever, most of the commercially available fatty; acids used in the production of metallicsoaps are; not pure materials but are mixtures of a number of fatty acids. Thus it can readily be seen'thatv it will be rather difficult to prepare a puremixture of two metallic soaps. Instead, the mixtures;

employed in the present invention will be madew up for the most part of the two preferred metallic; soaps with small quantities of other buts'imilar metallic soaps also being'present. The specific metallic soaps which it preferred'to use are the;

water-insoluble metallic'soaps of stear'ic acid;

reacting-a metallic compound with palmitic aci n ac a l h N s o rem nded the fatty material employed in preparing the metallic palmitates of commerce i often quite low. The fatty material most commonly employed in preparing commercial metallic palmi- Thus aluminum, magnesium, zinc, lead, barium,

calcium, strontium, etc. soaps of the fatty acids may all be prepared. Any desired procedure for preparing these soaps may be utilized.

has been cirited out hereinab'ove, it is rjatl'i'ergdiiiicuit" to prepare at metallic soap in the. p ur'eiorm', and usually there will be present'a varying amount of soaps of fatty acids similar to' thefatty acid which it is desiredjto have as the principal fatty acid component of the soap being prepared; Thus, for example, when aluminum stearate is prepared from a commercial stearic acidiobtained from animal sources the product obtained willact'ually contain a rather large per centage or aluminum palmitate and minor perccntages of aluminum soaps of other similar fatty acids as Well as the desired aluminum stearate.

When hydrogenated soybean oil is employed as the source of the stearic acid; the metallic soap will be approximately 90% aluminum stearate with theremainder of the soap being chieflyalun'iin'um palmitate. If a hydrogenated fish oil is employed as the source of the stearic acid in preparing a. commercial aluminum stearate, theproductobtained will actually contain on the av erager'r mioye to 50%; of the aluminum soapsof arachidic and behenic acids' with the remainder being-chiefly aluminum palmitate and aluminum stearate inapproximately equal percentages. It-

willbeunderstood that the term stearate when emplcyedin the specification and claims in con-'- nectionwith a-meta'llic soap'covers metallic soaps made" f-rom an'y of the abovetypes or sources of commercial stearic acid. Likewise as pointed out" above, the productknown commercially as aluminum palmitate is" actually a mixtureof aluminumscapsof-ooconut oil fatty acids. Thusin preparlriga-eutectic mixture of metallic soaps, it will-obviously be ratherdifficult to produce mix tu'resorenly two different metallic soaps. Ordiarily any mixtures produced will containat least small-percentagesofmetallic soaps other than the ones principally desired. However, this matteroi'having present soaps other than the ones principallydesiredis not as objectionable as it might seem since the diversity isonly in the fatty. acid components of the soap. It is well known that there is very little difference-in thephysical characteristics of the longchain satu-' Thus, for example, there'is a differencein melting point, of only about 20 0..

ratedifatty acids.

betweenpalmitic acid which contains 16"carbon atoms and behenic acid which contains 22 carbon atoms.= Consequently there will likewise be a close similarity between metallic soaps ofany one metal prepared from the different saturatedfatty acidsiin view of this close similarity and because oflthefact thatthe uses to which metallic soaps are usually put do not demand a high degree of purity, such metallic soap mixtures have become widely accepted and known usually as either metallic stearates or metallic palmitates as has been previously explained.

In preparing a eutectic mixture of thevarious metallic soaps it is desirable to employ as pure materials as possible. Consequently it" is preferred to employ eutectic mixtures of metallic stearates prepared from hydrogenated soybean oil. Thus eutectic mixtures prepared from the metallic soaps such as aluminum'stearate, zinc stearate, lead stearate, calcium stearate, magnesiumstearate, etc. form the preferred eutectic mixtures of the invention. However, other eutectic mixtures of metallic soaps may also be employed-and in fact certain other mixtures may be used .quite advantageously in preparing the products of the invention. Thus a eutectic mixture of lead stearate prepared from hydrogenated soybean oil and the zinc palmitate of commerce may b'eemployed v'ery' advantageously inthe production of synthetic waxes.

Although the methods usually employed in deftermining the proper proportionsof' the=com ponents of any given-mixtureof'materials inorder to giveraeutecticmixtureof such materials; are well known, a short discussion of the-m'ethom employed in the present inventionwill be givem In each'instance a series of mixtures'wasjpr pared from the metallic soaps from which th eutectic mixture 1 was. to be prepared; Insulin; series the relative proportionslof the metallic: soaps were varied progressively from mixture to: mixture gradually increasingthe amount-of one? soap therein asthe; amount of the other was"de"-'- creased. The melting point ofaeach mixturewasli then determinedand from the results; it :was very? easy to determine the required percentageofeaclis soap togive the eutecticmixture. Thistwasdone; by plotting the. percentage composition-of each; soap as-afunction of the melting-point; and inter? polating, where necessary, to obtainathe'seutectic composition.

As has been previously pointed out,.,i-t .is iratherc difficult to obtain a" metallicsoapinvthe:purer state, i. e.-without having metallic soapsEof-other; similar fatty acids admixed therewith. Cons'equently the eutectic mixtures'will in most cases; contain small amounts of metallic, soaps other; than those metallic soapswhich arethezpri-ncipala components of the mixtures. To some extenttthe: minorquantities. of these-=-soaps-.may affect the ratio between the principal-components in thee mixture; however, once .the composition-;.of-; the eutectic mixture of two ormore-particular-meta1* lic soaps is determined, that eutectic mixturemay be readily duplicated by employing. the;.same-. source materials. for the fatty acids in the metallic soapsas were employed when the-orig inal.de-.-.-

termination .of the compositionrcquiredio give. the eutecticmixture was made.-

In blending the fatty material with theeutectie. mixture of..metallic soaps, any desiredprocedure may be employed. We prefer to melt theefa'tty material and then slowly add. thereto theidesired amount of the eutectic mixture of the. meetallic soaps in powder.orgranulatedforme How-- ever, if desired, the eutectic mixturepf. metallic soaps may be melted prior to being} blended with thefatty material, and also the ,fattymaterial;

either solid or melted form, may be added tether liquid eutectic mixture instead of 5 adding the...

5. are such that they constitute a eutectic mixture." Also when the metallic soaps in solid forms are blended with the melted fatty material, the metallic soaps may be merely finely admixed or they may have been previously melted and thoroughly admixed and then allowed to solidify after which the solidified product is finely divided or granulated, e. g. by grinding. V

The total percentage of metallic soaps in the compositions of our invention may vary over a wide range. Thus synthetic waxes may be prepared in accordance with our invention which contain anywhere from about to about 90% of a eutectic mixture of metallic soaps. The characteristics of the synthetic waxes will vary, of course, as the percentage of the eutectic mixture therein is varied. Also the characteristics of the synthetic waxes will vary depending upon the particular combination of metallic soaps employed in each case to form the eutectic mixture. As a general rule, the higher the percentage of the eutectic mixture of metallic soaps in the synthetic waxes of our invention, the higher will be the melting points of the waxes. In most cases in order to have synthetic waxes of the most desirable characteristics, we prefer that the compositions contain between about 40% and about 70% of a eutectic mixture of metallic soaps with the remainder of the wax being made up of any desired fatty material which is normally solid at room temperature. Although the total amount of any given eutectic mixture of metallic soaps in our synthetic waxes may vary over a wide range, the composition of the eutectic mixture itself necessarily remains the same.

We prefer to employ eutectic mixtures of two metallic soaps in view of the ease in determining the relative ratios of the two components necessary to give a eutectic mixture thereof as compared to the difilculty encountered in determining the proper ratios of the components when a eutectic mixture of more than two principal components is desired. It is true, of course, as pointed out hereinabove, that it is rather difilcult to obtain any given metallic soap in a pure form as far as the fatty acid part of the soap is concerned, and thus the eutectic mixtures of metallic soaps which we preferably employ are not, strictly speaking, made up of only two metallic soaps. However, as was also pointed out above, when a metallic soap of any particular fatty acid is being prepared, any fatty acids which are present in the material being employed as the source of the desired fatty acid will ordinarily be so closely related both in chemical and physical characteristics to the desired fatty acid that the characteristics of the product obtained will be essentially those of the desired pure metallic soap. Consequently when employing such a metallic soap product as one of the components of a eutectic mixture, it may for all practical purposes be considered as being only the particular metallic soap of the desired fatty acid even though it will contain small amounts of soaps of other very similar fatty acids with the metallic ion concerned. In determining the composition of the eutectic mixtures which we have employed in preparing the products of our invention, we have found that such metallic soap products do for all practical purposes act essentially as pure components.

Although we do prefer to employ eutectic mixtures having only two principal components, eutectic mixtures containing more than two principal metallic soap products may be utilized if desired. it will of course be somewhat more-difficult to ascertain the required percentages of each component necessary to give aeutectic mix: ture in such cases. For a fuller understanding of to the following examples which aremerely illus-- trative and are not to be construed in a limiting sense. The melting points of the synthetic waxes prepared in the following examples'were determined in accordance with the American Society for Testing Materials method for determining the melting point of paraflin wax (see A. S. T. M. Standards 1946, part III-A, page 242, method 7 Example I 40 parts of hydrogenated sardine oil, melting at that temperature until a clear fluid was ob-- tained. On cooling a yellow, opaque, wax-like solid resulted. The melting point of the synthetic wax was 107-1l1 C. The synthetic wax was an excellent substitute for many of the naturally occurring waxes. 7

Emample II Formulae for other synthetic waxes of our in vention which are excellentsubstitutes for naturally occurring waxes are given below. In each case the method of preparation was the same that employed in Example I.

Parts- Eutectic mixture 6,0

6 parts aluminum stearate.

54 parts magnesium stearate. l Hydrogenated sardine oil 40..

Melting point 82 to 85 C.

I Parts Eutectic mixture -l 60 36 parts zinc stearate.

24 parts magnesium stearate. Hydrogenated sardine oil 40L Melting point 73 to 79 C.

Parts Eutectic mixture 60 24. parts zinc palmitate. '36 parts lead stearate. Hydrogenated sardine oil 40 Melting point 99 to 106 C.

Parts Eutectic mixture 60 24 parts zinc stearate L 36 parts calcium stearate. Hydrogenated sardine oil 4o Melting point to 93 c. v

Example III In order to determine whether the order of mixing the various components of the synthetic waxes had any effect on thecharacteristics' or the products obtained, a synthetic wax was prepared from the same materials employed in Ex-'-' the nature and objects of our invention, reference maybe had like characteristics;

7; ample:employingr the same-quantities of. each; material; as. in? Example.v I bllti using; a; different order ofnmixing. the materials; Thus. instead of: first preparing the eutectic mixtureof. the me.- tal-liczsoapseandthen admixing:suchrmixturerwith the; melted; hydrogenated: sardine oil; the: indi-- vidual' metallic. soaps were separately: added. to themelted hydrogenated;sardineroilzwith'thesoap. whichrwas add'eddirsti. .e. the aluminumzstearate, being: thoroughly admixed with the melted. fat: beforezth'ei other soap; i...e. the-.zincstearate; was addedztheretoi. The wax-like product whichwas obtainedEhad the same" meltingipoint aszthelprod- 'uct'aofExampleI;.andintall other. respects-it wasi identical with and had the same excellent waxlike characteristics asaithe; product of Example I.

Example I V synthetic wax-which was an excellentsub'-- sti-tutefor natural-waxeswas preparedby admixing eutectic mixture. of metallic soaps made up" 015.54 parts of magnesium stearate and 6 parts of aluminum stearate' with 40 parts of hydrogenated castor. oil.- The. synthetic wax was prepared byheating thehydrogenated castor oil to a temperaturelot about 55' (2., adding thereto the eutectic mixture of:- the metallic soaps, and then heating. the: mass up to 125 C, to" obtain a completely homogeneous product, Upon cooling,- the mass hardened to a waxy solid having excellent wax- It had a melting point of EDA-C.. Example V Another excellent synthetic waX was. prepared i557 the same procedure as was employedlin the previous example. The materials employed in preparing the synthetic wax were parts of ster'yl alcohol and parts of a eutectic mixture of metallic soapsmade u-p of- 24 parts-ofalum'inum stearate and36parts ofzincstearate; The product, which had a melting point of"93-95 0., had excellent wax-like characteristics.

Example VI Palm oil fatty acids were employed to prepare a synthetic wax by admixing therewith a eutectic mixture'ofzin'c stearate' and magnesium stearate. The product was prepared in the same manner as the product of Example IV employing 36' parts of zinc" stearate, '24 parts of magnesium stearate and 40 parts of palm oilxfatty'acids'. The product, which was an excellent substitute for natural waxes, had a melting point of -83 C.

Emmple- VII-- Hydrogenated sardine oil WaSCOIIVGItGdI to a product having very good Wax-like. characteristics by admixing only 5 parts of av eutectic mixture. of metallic soaps of thesame composition as was employed in Example I .with 95 parts of the hydrogenated sardine oil. The synthetic wax was prepared by the same procedure as wasemployed in Example I. Although the synthetic waxhad essentially the same melting point as thBrhYdI'O genated sardine oil, in all other'respectsrit was.

considerably superior to the hydrogenated sardine oil as far as Wax-like characteristics were concerned.

Example VIII A .-eutectic: mixture of metallic soaps 1 made up of'136- parts of. lead istearate and z l-part of zinc palmitate was admixed with 40 parts of rosin byithe: same process as was employed in Example IV:. The product, which. hadamelting point-of.

829 831 6;, had excellent7waxelikeacharacteristicsi Eitampl IX 7 V Ten parts of hydrogenated sardineoil were ad mixed with parts of a: eutectic mixture of metallic 1 soaps made up' -of'36 partsv of aluminum stearate and 54 parts of zinc stearate. The prod;- uct wasprepared by the same procedure employed'dniExample I: The syntheticwaxiwhichwas: obtained had-a melting point of 114-1'15"C. It had very good wax-like characteristics;

EaccmnplaXv excellent syntheticwax'was prepared from coconut oil and a eutectic mixture of calcium stearate andainc stearate. The eutectic mixture was madeup-of 36 parts of *calcium ste'arate' and 24 parts of zinc stearate. It was admixed with llpar'ts of the coconut oil employing the same procedure a's' was-used in Example A n-ex' cell'ent synthetic wax having a melting point of 6'5-l'0 G. was obtainedl Example XI Eighty parts of hydrogenated sardine oilwere admixed with 20"parts' of a eutectic mixture of zinc stearate and aluminum stearate in accordance *withthe process of Example Ii The eutectic mixture of metallic soaps 1 was made up" of 1 2 parts of zinc stearate and 8 parts of aluminum stearate; The synthetic-wax which was obtained was an excellent substitute for natura-Twaxesl Example XII An excellent synthetic waxwas'prepar'ed from hydrogenated soybean oil and a eutectic mixture of zinc stearate and aluminumstearate: The product was prepared"in* accordance with the process of Example- IV employing departs of hydrogenatedsoybeanoil. 36 partsof zinc stearate and 24 parts of aluminum stearate; The waxy solid which was obtained ha-da melting-pointof 1053-106 C. It was an excellent substitutef'or natural waxes.

I 'hesyntheticwaxes'oi our invention'may have incorporatedtherein dyes; pigments, other coloring matter, etc.

It wouldbe possible; of course; to raise the melti ng' 'point of'a fattymaterialnormallysolid at room temperature by blending with-such fatty materialonly' cnem'etall-ic' soap instead of a eutecticmixture of'such soaps. In fact'the' increase in' mel-tin'g point wouldbeev-en'greater in most" cases when only one soap was employed than when a eutecticmixture of so'apswa's uti lized. However we have found that compositions prepared using a single metallic soap have 'no-' wherenear as satisfactory wax-like characteristics as'those' prepared from a eutectic-mixture of metallic soaps. For one thing the synthetic waxes of our invention have a greater fluidity i-n-the melted statethan compositions prepared usi-ng'only' a single metallic soap. Thusthecom positions of our invention are much more're'a'dily handl'ed'and applied in a fluid con'diti'on'than are compositions preparedfroma fatty material and only one metallic soap. Also Qursyntheti'c waxes are superior-in theirfracturecharacteristics; have greater plasticity, are more opaque,- and in general, their wax-like characteristics are much more superior to compositions prepared using only'one metallic soap. Our compositions have such excellent characteristics that theymay be used t'o' entirely-replace natural waxes for'many'purposesw Because of their high opacity our synthetic waxes are particularly valuable for paper coating purposes. The presence of the metallic soaps in our synthetic waxes gives them excellent Water repellent characteristics. The cost of our synthetic waxes is less than most of the natural waxes, and therefore our products may be used for many purposes where it is not commercially feasible to employ the more expensive natural materials.

Having described our invention what we claim as new and desire to secure by Letters Patent is:

1. A synthetic wax consisting essentially of a mixture of a material normally solid at room temperature which material has as a principal constituent a substance selected from the group consisting of abietic acid, saturated fatty acids containing more than 9 carbon atoms and saturated fatty alcohols containing more than 11 car bon atoms, and a eutectic mixture of solid polyvalent metal soaps, said eutectic mixture of solid polyvalent metal soaps making up from about 5% to about 90% of the synthetic wax.

2. A synthetic wax consisting essentially of a hydrogenated fatty oil and a eutectic mixture of solid polyvalent metal soaps, said eutectic mixture of solid polyvalent metal soaps making up from about 5% to about 90% of the synthetic wax.

3. A synthetic wax consisting essentially of a mixture of a material normally solid at room temperature which has as a principal constituent a substance selected from the group consisting of abietic acid, saturated fatty acids containin more than 9 carbon atoms and saturated fatty alcohols containing more than 11 carbon atoms, and a eutectic mixture of polyvalent metal stearates, said eutectic mixture of polyvalent metal stearates making up from about 5% to about 90% of the synthetic wax.

4. A synthetic wax consisting essentially of 'a hydrogenated fatty oil and a eutectic mixture of polyvalent metal stearates, said eutectic mixture of polyvalent metal stearates making up from about 5% to about 90% of the synthetic wax.

10 5. A synthetic wax consisting essentially of a hydrogenated fatty oil and a eutectic mixture of aluminum stearate and zinc stearate, said eutectic mixture making up from about 5% to about 90% of the synthetic wax.

6. A synthetic wax consisting essentially of a hydrogenated fatty oil and a eutectic mixture of lead stearate and zinc stearate, said eutectic mixture making up from about 5% to about 90% of the synthetic wax,

7. A synthetic wax consisting essentially of a hydrogenated fatty oil and a eutectic mixture of zinc stearate and calcium stearate, said eutectic mixture making up from about 5% to about 90% of the synthetic Wax.

8. A synthetic wax consisting essentially of hydrogenated soybean oil and a eutectic mixture of aluminum stearate and zinc stearate, said eutectic mixture making up from about 5% to about 90% of the synthetic wax.

9. A synthetic wax consisting essentially of hydrogenated soybean oil and a eutectic mixture of lead stearate and zinc stearate, said eutectic mixture making up from about 5% to about 90% of the synthetic wax.

10. A synthetic wax consistin essentially of hydrogenated soybean oil and a eutectic mixture of zinc stearate and calcium stearate, said eutectic mixture making up from about 5% to about 90% of the synthetic wax.

JOSEPH CUNDER. FRANCIS J. LICATA.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,276,507 Ellis Aug. 20, 1918 2,027,389 Lazier Jan. 14, 1936 2,320,645 Nill June 1, 1943 2,380,960 Fraser Aug. 17, 1945 2,483,259 Budnar Sept. 27, 1949

Claims (1)

1. A SYNTHETIC WAX CONSISTING ESSENTIALLY OF A MIXTURE OF A METERIAL NORMALLY SOLID AT ROOM TEMPERATURE WHICH MATERIAL HAS AS A PRINCIPAL CONSITITUENT A SUBSTANCE SELECTED FROM THE GROUP CONSISTING OF ABIETIC ACID, SATURATED FATTY ACIDS CONTAINING MORE THAN 9 CARBON ATOMS AND SATURATED FATTY ALSOHOLS CONTAINING MORE THAN 11 CARBON ATOMS, AND A EUTECTIC MIXTURE OF SOLID POLYVALENT METAL SOAPS, SAID EUTECTIC MIXTURE OF SOLID POLYVALENT METAL SOAPS MAKING UP FROM ABOUT 5% TO ABOUT 90% OF THE SYNTHETIC WAX.