Патент USA US2408299код для вставки
Patented Sept. 24,, 1946 2,408,297 ’ UNITED STATES PATENT ’ OFFICE ' ‘2,408,297 BITUMINOUS coMrosrrroivs' ‘ " Richard H. Cubberley, Ridgewood, and Frank W. .Yeager, Englewo'od, N. J ., assignors to The Pat ‘ cut and Licensing Corporation, New York, N. Y., a corporation of Massachusetts _ ‘ Ne Drawing. Application May‘11,,1944',1 ' Serial No. 535,194 2 Claims. (01. 260-'—28) > i ‘ V'I‘his invention relates to compositions of nor mallyls'olid, heat lique?able bitumen, and is more particularly concerned with the provision of such ' 2- ' 5% 'cetyl acetamide ‘will raise thesoftening point of they asphalt from l50-l60°‘F. to 235-245” F.,' and, simultaneously, will‘cause theviscosity of the asphalt at 300°F. to be greatly reduced (1. e., compositions having properties and characteris tics distinctly different from those. originally 5 to 350 C. P. S. at 300° "F.). In addition to this radical lowering of the viscosity which renders the asphalt highly ?owable at 300° F., it has been found that the thus modi?ed asphalt will possess highheat'stability, as indicated bya sharp sof wise be unsuitable. , ‘One object of the present invention is to pro 10 tening point, ‘and _will not v\?ow ‘or soften to a vide heat lique?able asphalticcompositions char- ‘ material‘ extent at'temperatures up to approxi-L mately 10° F. below its adjusted softening point. acterized by a relatively high softening or melting Thus, in the example cited, the asphalt, having point and byv an unusually low viscosity at tem a softening point of 240° F. will not soften mate peratures at which an asphalt of similar soften possessed by the bitumen, whereby to render such compositions suitable for those types of applica tions where the bituminous material} would other ing or melting point is normally-highly viscous. rially at 225-230° F. Another object is to provide asphaltic compo sitions in which the normally high adhesive strength of the asphalt is modi?ed to a perma nent, moderate tack. ' A further object is to provide heat lique?ablev asphaltiov compositions which, while possessing ' ‘ ’ The addition of cetyl acetamide to the asphalt also serves to block out or mask the inherent high adhesiveproperty. generally characteristic of all asphaltio'surfaces. The modified asphalt is there fore suitablefor use as a laminant and coating in the manufacture‘ of certain types of laminated‘ wrapping materials’ which are'wound into 'rolls capable of being readily unwound as required for use.‘ The desirable minimum amount of adhesion tures up to about .10" F. below the softening point of the asphalt, will also be ?exibleand non-brittle 25 between‘ layers ‘of the‘ wound wrapping material at temperatures at which the‘asphalt is normally that are in direct contact with each other may high heat stability, 1. e., they will notsoften or tend toi?ow to any material extent at tempera" brittle and inflexible. 'The'foregoing and related objects may beat 7 be termed‘ the ‘_“storage' adhesion” characteristic of theifnaterial. ‘ It is noteworthy that. the pres tained, in accordance with the present invention, ' ence' of the cetyl acetamide in the asphalt‘ come‘ - by treating, an asphalt inlsuch manner, as will 30 position does not adversely affect'the desired ad which render it unsuitable for certain types of hesion developed when the molten compound is brought into contact with'the materials that are to be, saturated and/or coated therewith, and saturating, coating, adhesive and laminating ap then allowed to cool. be more fully explained hereinaftenthat those properties and characteristics .of the asphalt plications will be permanently modi?ed to the _ extent required for such applications. , . ' ' ' A commercial form of cetyl acetamide, which is a synthetic wax, is available on the market under vthe proprietary name of “Acrawax C." A typical example of an asphalt which may This synthetic wax has a softening point of be used in the practice of the present invention is a grade customarily used in the manufacture ' approximately 280° F. and will increase the sof of roo?ng shingles and the like.. This-grade of 40 tening point of the foregoing grade of asphalt on an average of ‘approximately 15° for each 1% of asphalt may have a softening or melting point of 155°VF.‘, a penetration of 14 at 32° F.',‘36 at ‘77° F._ the material added. , , 7 and '79 at 115° F. Such anasphalt' possessesv a, The?asphalt composition which has been modi relatively high viscosity, for example, 680 C‘. R8; ?ed in the vmanner above indicated may also be at 300° F., and is a very sluggish material, at rendered flexible‘ and non-brittle at temperatures. such temperatures‘. Cooled ‘and hardened ?lms of the order of 0° F. This may be accomplished‘ of ‘this grade of asphalt are extremely brittle and’ by blending with the previously modi?ed asphalt. composition a small amount of a tacky, viscous substance which has arelatively high molecular By ‘adding to a quantity of, the aforementioned 50 weight, ‘and which functions, in part, as a plas grade of asphalt in heat lique?ed condition a ticizer for the asphalt._ One example of this type small proportion by weight of cetyl acetamide, of substance is a polyisobutylenecompound hav ing a molecularv weight within the approximate several’ propertiesand characteristics of the as phalt are thereby radically altered.‘ It has been, range of 500-2500. .fSuch compounds are commer found, for example, that the addition of only cially available under the trade name of “Vistac.” in?exible at relatively low temperatures of say _ 0° F. and lower. ' V 2,408,297 3 4 The blending with the aforementioned asphalt composition, for example, of about 10% of Vistac suitable means. Because of the high softening point of the compound, the heat-sealed laps de No. 1 has been found to increase the penetration of the resulting composition from 15 to 21 at 32° velop a ?rm bond. Another practical application for which the composition of the present invention is particu larly suited is for coating or lining the interior F., without however materially affecting the sof tening point of the composition, viz. 235—245° F. surfaces of containers or the like which are in The thus blended composition is ?exible and non brittle at temperatures as low as approximately 0° F. An unmodi?ed asphalt of a grade having a similar softening point is characterized by ‘a penetration of 0-3 at 32° F., and is exceedingly‘ brittle at these low temperatures. The presence of the Vistac. in the-asphalt com position also serves to lower the ‘viscosity of.‘ they resultant composition still further, e. g., from 350 C. P. S. down to 280 C. P. S. at 300° F. tended to be ?lled with substances at tempera tures as high as about 10° F. below the softening point of the composition. In such types of ap plication, the composition having a softening point of about 240° F. may be brought to highly fluid condition by heating it to approximately 300° ?lling ‘the container therewith and . thereafter‘ removing the excess as by draining, whereby a substantially uniform coating ?lm of When the modi?ed asphalt composition con-l - ; the composition remains on the interior surfaces, which will set and harden upon cooling. The low taining Vistac is used as a laminant and coating viscosity characteristic of the composition, even in the manufacture of wrapping material, the presence of the Vistac in the composition imparts 20 when it has cooled down to temperatures only about 20° F. above its softening point, permits the t0 the Wrapping material a most desirable char containers to be rapidly ?lled and then rapidly acteristic. which may be termed “operational drained with a substantially uniform, continu tack.” It is this particular characteristic which ous and relatively thin lining ?lm remaining on enables a material made with the composition the interior surfaces of the containers. The de of the present invention to adhere to itself under sired interior coating may be obtained, under moderate manual pressure when applied as a wrapping around an article and overlapped upon such ?lling and draining conditions, even where the containers have interior ?ttings which pre itself. In order to explain ‘more clearly the unique sent avnumber of irregular, discontinuous sur properties of compositions made by modifying 30 faces. After the coating ?lm has cooled and hard asphalt in the manner above described, several practical applications, for which the. composition ened, the container may be ?lled with the de sired contents at a temperature as high. as, say is readily adapted, will be described in detail. 220-230° F. By virtue of the heat stability of One such application is in the. production of an the lining, the contents may be poured into the adhesive wrapping material, wherein a sheet of container at temperatures as high as about 10° suitable material, such as woven cotton sheeting, F. below the softening point of the lining com kraft paper or the like may be run through a vat containing the highly ‘fluid composition heated position without adversely affecting the lining, to approximately 300° ‘F. When. this sheet emerges from the vat, a sheet of Cellophane, kraft paper, metal foil or similar material, which. has at least its outer surface coated with the same composition, islaminated thereto by pass“ ing the two layers of. material vbetween a pair of. combining roll's, which press the layers together -'_ provided that the contents are not. of themselves. a solvent. for asphalt. Moreover, the coating provided by the present composition is quite ?exible, as is indicated by its relatively high penetration at 32° F., even though possessing a high softening point, and The-laminated material is then permitted to cool slowly while travelling over suitably positioned is less likely to. shatter or crack, when subjected to mechanical, shock at temperatures of the or der of 0° F. than would normally be the case with an‘ unmodi?ed asphalt of similar high soft rolls and is then convolutely wound up in rolls ening point. and squeeze, out the excess of the composition. for storage or shipment. ' , The present composition also posssess other ’ The “storage adhesion” of the wrapping mate noteworthy characteristics, namely, its chemical rial‘ made with the composition asabove described inertness, non-corrosiveness, and resistance to water. These characteristics, normally inher ently present in the unmodi?ed asphalt, are pre served by reason of the selection of modifying is manifested by the ease with which the ma‘ terial may be unwound from the roll with ap plication of normal amount of force and without damage to the material. Had an unmodified asphalt been used as, the laminant, and coating inthe manufacture of the above-described ma agents, such as the synthetic wax and polyiso butylene above speci?ed, which are themselves chemically inert, non-corrosive, and water re sistant. terial, the strongly adhesive character of the asphalt, would‘ have prevented the unwinding of 60 Satisfactory compositions of the present inven tion may be: prepared using 73-95% asphalt hav the rolled material without tearing or Otherwise ing a softening point of approximately 155° F-., damaging the material. 2-15% Acrawax C and 13-12% Vistac, these pro In using the laminated material as an adhesive portions being by Weight of the compound. Other wrapper, sheets of su?icientsize are used to pro vide for an overlapping of the wrapping mate grades, or types of asphalt, possessing either ap preciably higher or appreciably lower softening rial upon itself When placed around an article being wrapped. The overlapping portions of the points than the one indicated, may be modi?ed by combining" therewith the foregoing modifying wrapping material are brought into contact with agents in amounts, within the range above speci each other with the application of'moderate man um‘ pressure, thus developing “operational tack” ?ed, depending upon the properties of the se in su?icient degree to hold the overlapping, por lected» asphalt and upon the requirements of ap plication. ‘ tions together. The wrapped articl‘emay be fur ther protected‘, if ,desired,yby sealing the, over There may be thus provided in accordance lapping portions of the wrapper by the applica with the invention compositions consisting tion of heat in any suitable manner and by any 75 mainly of a relatively inexpensive bitumen which 2,408,297 5 is rendered suitable for many types of applica tions as saturants, coatings, laminants and ad 6 2. An adhesive, waterproof composition having a softening point of 235-245D F. and characterized hesives for which the bitumen in its unmodi?ed , by its high ?uidity at 260-300’ F., heat stability form is entirely unsuitable. We claim: ical inertness, non-corrosiveness, and ?exibility 1. An adhesive, waterproof composition char acterized by its high ?uidity at a temperature as position comprising 73-95% asphalt normally at temperatures as high as about 225° F., chem at temperatures as low'as about 0° F., said com having a softening point of approximately 155° F. and a penetration of about 36 at 77° F., 2-15% below its softening point, chemical inertness, 10 cetyl acetamide wax and 3—12% of a polyiso butylene having a molecular weight within the . non-eorrosiveness, and ?exibility at temperatures range of approximately 500-2500. as low as about 0° F., said composition compris ing '73 to 95% of a normally solid asphalt, 2 to RICHARD H. CUBBERLEY. 15% of cetyl acetamide wax, and 3 to 12% of a FRANK W. YEAGER. polyisobutlyene having a molecular weight is within the range of approximately 500-2500. low as 20° F. above its softening point, heat sta- - bility at temperatures as high as about 10° F.