1836,940 present specification wherein it is intended to claim the invention as broadly as possible in view of the prior @@t. WI-iat is claiiil -ied is. 1. The process of vulcanizing rlibber WI-ii-,I-i cciiiprises heatinc, t n@ixture of rubber and stilfi-i in th@@ ' 5reseiice of an antioxidant comprising a reaction product of an aryl ainine witl-i a clioxv-diarvl h,,tlogen sub@o stituted -Daraffine. 2. Th@ i)rocess of vtilcanizing rtibber which comprises heal@-@ng t mixture of rubber and si,ilftir in the 1:)res,,-nee of an tiiti-oxidant coniprising a rep@ctioi-i pl@oduct of an aryl amine. 15 with a dioxy-diai,yl chlorine substituted paraffi.ne. 3. The i)rocess 6f vulc,,tnizing rtibber -",hich coinprises heatin@z a mixture of rubber and sulfur in the pi@esence of an anti-oxidant 20 con-iprisino- a i-eaction product of an aryl an-iine -v@,iCh a dioxy-diaryl chlorbutane. 4. The process of vuleinizijig rubber which coinprises heating a mixtur6 of rubber and stilf tir in the presence of an anti-oxidant sic comprisiiig a reaction product of an aryl amine ivitli dioxy-diiiaphthyl chlorbutane. 5. The process of vuleanizin- rubber whieb comprises heating a nlixture of rtibber and sulfur iii the presence of an anti-oxidint 3'-' comprising the reaction product of orthotoluidii'le with dioxy-dinaphthyl chlorbutane. 6. The v-Lileanized rtibber prod-Liet produced by heati-ng- a n-iixture of rubber -tnd sulfur in the presence of an anti-oxidaiit 35 coliil)rising a re,,tetion product of an aryl amine with a dioxy-diaryl halogen substituted paraffine. 7 ' The vi-ileanized rubber product produced by heating a mixture of tubber and 40 sulfur in the presence@ of an anti-oxid,@tnt CoTprising a reaction product of an aryl amine @vith a dioxy-diaryl elilorine substituted ptraffine. S. The vtileanized rubber product pro45 duced by heatijig a inixture, of rubber and sulfur in the presenee, ()f an anti-oxidant coi-nprising a reac@tion prod-Liet of fin aryl amine with a dioxy-diarylchlorbutane. 9. The vuleapized rtibber product pro_ "O duced by heating a mixture of r-c@bber anc, sulfur in the presence of an anti-oxidant comprising L reaction product cf an aryl amine with dioxy-dinaphthyl-chlorbutane. 55 10. The vulcanized rlibber product prodtleed by heating a mixture of rubber and sulfur in the presence of an anti-oxidant comprising a reaction product of ortho-toluidine with dioxy-dinaphthyl-chlorbutane. 60 11. The process 6f vulcanizing rubber ivhich comprises heating a mixture of rubber and sulfur in the presence of an anti-oxidant comprising a reaction product of an aryl amine wit a dioxy-diaryl substituted alkyli65 dene halide. 12. The process of vulcanizing rubber which comprises heating a mixture of rubber ancl sulfur in the pre@ence of an antioxidant comprising a reaction product of an aryl amine with a dioxy-diaryl substituted alli:ylidene chloride. TO 13. The process of vulcanizing rubber which comprises.heatinl, a mixture of rubber i,nd sulftir in the presence of an antioxidant coinprising a reaction product of an aryl amine with a dioxy-dinaphthyl substituted alkylidene chloride. 14. The prccess o,f vulcanizing rubber which comprises heat.ing a raixture of rubber anct sulflir in the presenee of an anti- so o:si.clant domprising a reaction prcduct of an aryl amine with a dioxy-dinaphthyl substittite(-lalkylidene chloride, said alkylidene grolip containing less than five carbon at6ms. 15. The process of vulcanizing rtibber 85 which coinprises heatiiig a mixture of rubber and siilf tir in the presence of aia antio-Nidaiit com-prisino, the reaction product of substantiall-v three mols of ortho-toluidine aiid @.ubstantially one mol of dioxy-dinaphgo tliyl-chlorbutane. 16. The vulcanized rubber pr(>duct Prodlicecl by heating a mixtlire of rubber and Sulfur in the presence of an anti-oxidant cornprisiilg a reaction product of an aryl amine 9@; w@ith a dioxy-dia@yl substituted alkylidene halide. 17. The, vulcanized rtibber product pro(Iiiced by heiiting a mixture of rubber a-n-d sulfur. i-n the presence of an aiiti-oxidant comprising a reaction product of an ary, 100 amino with a dioxy-diaryl substituted a.1- kylidene chloride. 18. The vulcanized rubber product produced by heating a mixture cf rubber and 105 sulfur. i.n the p@esence of an aiiti-oxidant comprisiii- a reaction product of an arvl amine witl-i a dioxy-dinaphthyl substituted all,-ylidene chloride. 19. The vlllcinized rubber @product pro- 10 (ILiced b3T heating a mixture of rubber aiad sulfur. i.n the presence of an anti-oxidant coi@iprising a ireaction product of an aryl amine wi 'th a, dioxy-dinaphthyl substituted all-,vlidene chloride, said all@ylidene c,,Toup 115 C(@)lit,,tining less than five carbon atoms. 20. The vlileanized rubber product proclueed by heating a mixture of rubber and stilf-Lir in the presence of an anti-oxidant coniprising the reaction product of substan- 120 tially three mols of ortho-toluidine and substantially one mol of dioxy-dinaphthylchlorbutane. In testimony whereof I hereunto affix my signature. 125 ROBERT L. SIBLEY. 130

Patented Dec. 15, 1931 1,836,940 UNITED@@ STATES PATENT OFFICE@ ROBERT L. SIBLEY, OF NITRO, WEST VIRGINIA, ASSIGNOR TO THE RUB13ER SERVICE LA330RATORIES COMPANY, OF AKRON, OHIO, A CORPORATION OF OHIO AGE RESISTING VULCAlqIZED RUBBEP. PRODUCT AND PROCESS OF XAMUFACTURING SAME No Drawing. Application filed October 11, 1930.. Serial No. 488,195. The present invention relates to a proce,ss for the manufacture of vulcanized rubber a,,id the products obtained -th6reby. More pa,rticularl3,, the invention is directed to an iniproved process of manufacturing vuleanized rtibber and the like wherein tfiere is incorporated into a, r-Libber mix of vuleanizatioii ebaracteristies, a compound of the type @re here@.nafter disclose wh by anti-oxidant 20 or age resisting, properties are developed in the vulcanized rubber product. @The inventioii will be understood from the following (-I e s c,, . iptioii and ex,,tmples wherein a preferred n-iode of operating the invention is fully set Is fortli and described. It is well kiiown that rubber deteriorates more or less rapidly when exposed to air;heat "Ind slinligjit ind that such deterioration is c,@h,,iractei.ized bv a loss in the tensile strength, 20 resi-liencv and other @desirable-;properties of the rqaterial. It has now been found accordi-.icr to the present invention that such deterioration can be very -reatly lessened if there, 25 be incorporate-d in the rubber mix a com1)(uiicl of the ellass hereinafter set forth. The dge resistint2: characteristics of a vtilc,,,i,,ized rlibber pr6@luct can be readilv aseerne cl bv subjectinz sam-ples of the vuleanI 30 i.zed i3rodLiet to an accelera%led aging test Ai,lierein portio,,is of the cured riibber product are si-ib ected in a boinb to the action of oxy,,)-en under pressure and maintained f6r sev-. holirs at an elevated temperature. The 3 ,5 tl,,Cated stmples are then examined and tested tlae restilts compared with similar results (-)@t)-@,aiiie,d by testin-'the unaged vulcailized -- "I '94-6,@k. 'rhe detel-ioration in properties suft fered as a result of th idati6n treatment e ox is indicative of the result that would normauy be expected from that particular stock dur'ing severa,l years of iiatuial aging depending on the duration of the test. : Such @a test is known as the Bierer7l)@vi@. aging test. The neW class of -6xidaiit or age resisting matbrial which have 4een found upon ir@corporation into a. rubber stock to impart slich excellent age@'resi ting qualities @to the 'vulcanized prodtict thdt portion t]@ereof, 50 Nvhen stibjected to the artificial azing tests de@eribed, undergo onl@ a relativelv sma.11 loss in tensile strenoth aild other ciualities, C i OMprises a r6action@rod-Liet' of an aryl amine -v@,ith a dioxy-diarvl-haloz6n substituted par- "5 affine. @ Oi@ie me I od wherebv one, of t]@e preferred class 6f antioxidants, lor e@am'ple the reaction pi@oduct:of diox,ydinaphth@i-@chl6rbuso tane and ortho-toluidiiie, may be @r@pare4 is as follows: Dioxy-dinaphthyl-chlorbutane and orthotoluidine in@'the ratio 6f substantially one moleclilar proportion of the former com- 65 potind to an excess over siabstantially four molecular I)roportions of the @latter compound 'table container d ive re placed in Sul an he ated, preferably in the re e of@orthop toluidine hydrochloride, at a temperature of 70 approximately 190 to 2051 C. with agitation f6r subst;antially three to four hours. After cooling t;o approximately 30' C., the exe6ss of unreacted orthotoluidine w s removed by 75 n-i@l@ing the sol-Litioii alkaline aild distilling, or if convenient or desirable, by washing with h dil-Lite acid, for example hydrochloric acid, alid then washing the product with water. It is thotight that the reaction representinir the 80

1,836,940 preparation of the above compound proceeds hydrochloride, in a, rnanner analogous to that as follows: described above. It is thought that the reacc E[3 CH3 CIE[2 @H2 @H.NIEECeH4.C.H3 +4NH2-CGH4'CH - U\@\ I / 0 H 0 NH HN + HC1.H@N.C@H.-CH@ + 2H-.O I CeH4-CH3 CG'Ht'CHS The, product prepared as described was com- tion repi-esenting the preparation of the com15 pounded in the well known manner in a typi- pound described proceeds accordin- to the cal rubber tread stock comprising following equation: CH$ CH3 H2 @H2 20 H-C-NHCcH5 85 + 4c6H5NH2-0 OR H 90 25 + 2H20 + CcH5NEI@-HdI. H6 COH5 100 parts of smoked sheet rubber, The d thiis prepared was incorporated 10 parts of zinc oxide, @ I pro Ile' 40 parts of carboi2 black, In a rtibber inix in the usual manner comparts of a blended mineral oil and rosin, 3 ) prising . -5 parts o'f siilfui I pirt bt@diphenyl guaiiidine, 30 1 part .of -the anti-oxidant described. 100 parts of smoked sbeet rubber, P. 5 10 p a r t s o f z i n c o x i d e , The stock was then-vulcanized by heating 40 1),irts of carbon black, - 2 pa,ts of a bleuded mineral oil and rosin, -,heets of the -said, stock in a press in the well 3 2 5 parts of sulfur, 1 part,of dipheiikl guanidine, known maiiiier for clifferent peiiods of time 1 part of the aiiti-oxi0ant describecl. at the temperattire given by,forty pounds of --3 5 steam -pressure per square inch. Portions of The compolinded rtibber stock ivas then cured, as in the previous example, by lieating the stock cured as set forth were then artifl- - i--,, a press for differen' periods of time at cially a,(red by heatinly T)ortions of said stock the t-einperat,,ire exliibited by forty pounds in' a,n ox3,gen bomb in,the manner described :of stectlll PrE,,ssuri, . ei, sqtiare inch. The cured for 39 hours at,a,temperatlire 6f 70' C. and P rubber prodiic' -v,-.qs ti-ieii qlged in the man4o an oxygen pressuro, of 300 pounds per square I lier set fortb fo,. 39 ho-Lirs at a teiilperlture in(@h. A comparison between the tensile -inc., of 700 C. ,incl iinder ,tii oxygen pressure ofmoclulus properiies,of the, aoed and una(,ed t@ 300 pou-ids per square inch. The tensile data viilcanized rubber rodu t is -iven in the f o'l P C -1 rubber 16wing table: of the aged and unaged vulcanize, produ ct follow in Table II. Table I 45 Elasticity Table lI MO(i@Llus . I Teiisii,,@ Ultimate Cure Hours of lbs /in.2 in.elongabreak in elongatioia aged tio3as of ]"Sticity at 300% lbs@/in.2 percent Modulus of F' Tensile at Ultirnate 500% Cure HOUTS " 'long"' break in elo-,gation lbs./in 2 at tions of mins. aged 300@@ lbs./i n.2 per cent 50 30 0 832 2170 309 5 640 500% --5 30 913 2040 229 5 560 - 60 0 1300 3095 439 0 660 30 0 900 2255 331 5 630 60 '39 1305 2590 286 0 560 30 39 621 1400 169 5 575 90 0 1490 3390 443 5 630 0 12@5 3230 432 0 610 90 39 1525 2783 280 3 520 60 39 11@5 2@io 226 0 510 90 0 1725 3,00 452 5 565 90 30 1405 238 5 470 55 The data set forth in Table I -,Iiows that fl-ie if@o preferred class of ant-i-oxidant rnaterials, for example a reaction product of dioxy-d inaphthyl-clilorbtitane and ortho-toluidine, possess particularlydesirableanti-oxidantl)i-operties. 60 An.other example olf the preferred class@ of I iiti-oxidaiits ivas prepared b re,,Lcting siib@ )T Aantially one molecular proportion of diox - y d.inaphth3TI-chlorbut,tiie@ witl-i aii exc--Ss over substantially f6ur iiiolecular proportions of 6-5 aniline, preferably in the presence of aniline From tl-te clata set forth in T-,tble II it is appareiit that the reL,.cti-oT-i produe'Ll of dioxy--i,,ipb.th 1-chlorbut,.tiie ,tnd aniliiie possesses c,li i y lu-he d.esirable properties o'L the i-@ preforred el-@ss of coiupounds. A f tirther exaiit)le of the preferred class of a-, -,iti-o-Kid,,tnts -vvas prepared by reacting si,,bstintiilly oiio 1-aolecular propoeion of dioxv-diliaphthylchlorbutane with ail excess

1,8@6,940 over substantially four molecular propor- I A further example of @tlie preferred class tions of alpha-naphthylamine, preferably in of anti-oxidants was prepared by, reacting the presence of alpha-naphthylamine hydro- substantially. one molecular proportion of chloride, in a manner analogous to that dedioxy-dinaphthylchlorbiltane with an exscribed above. It is thought that the react.ion cess, over s@bstantially f our molecular pro- 70 representing the preparation of the eom- portions of paraphenetidine, preferably in pound described proceed8 accordin-- to the the presence,, of para-phenetidine hydrochlofollowing equation: ride, in a manner analogous to that described CHI CIE[3 .10 75 0 ]E[2 @H-NHCIQH7 1 +4CIOUTNIl," 80 +Ci@H,NH..HCI+2H@O The product thus prepared was incorporated above. It is thoulyht that the reaction rep, usual manner comresenting the p ep-a 20 in a rubber mix in the r ration of the com ound 85 p prising describe d proceeds according to the following equation: CHI 25 CHI H go @HCI CH3- CHI--@-NHCOH40ciH$ colr4oc2lr5- 30 N H R 9 5 0 o l r 4 @ G H 4 + HCl@H2N-CoIl4OC2Hs + 2H.0 @C2]ff$ 6C2H$ 100 parts of smoked sheet rubber, 10 parts of zinc oxide, The product thlis prepared -%vas incori)orated 3,5 40 partii of carbon blacy, 100 2 parts of a blended mineral oil and rosin, in a rubber mix in the usual mafine-r com3 25 parts of sulfur, 1 part of diphenyl, guanidine, prising I part of the anti-oxidaiit described. 100 13arts of smoked sheet rubber, 10 p a r t s o f z i l i c . o x i d e , The compounded rubber to(-k wAs fhen 40 parts of carbon black, 40 cured, a,s iii the fi,rs'(, mentioned exaliitle, by 2 par.ts of a blended mineral oll,and rosill, 3.25 I)arts of sulfur, 105 ileatinz ii-i a press for different periods of 1 ' part of diphenyl guanidliae, I part of the anti-oxidant described. time @t' tb.e temperature exhibited by forty pounds of steam pi-essure per sqttare i-icl@. The,- compotinded rtibber stock ivas then The, cured rubber product wtts the-n aged ii-i cured, as in the first mentioned example, by 4,5 the manner set forth for 39 1-ioui-s at a tem- heating in a press for di:fferent periods of 110 perature of 700 C. under an oxygeii pressiire time at the teinperature exhibited by forty of 300 pounds per square inch. Th(@ teiisile pounds of steam pressure per square@ inch. data of the aged and unaged vulcanized rub- The cured rubber product was then aged in ber product follows in Table III. the m,,inner set forth for 39 hours at a tem50 Ta'ble III perature of 700 C. under an oxygen pr.essure 11,5 of 300 pounds per sqtiare inch. The tensile Cur() Hours Modulusof Elasticity Tensile at Ultimat, data of the ao,,ed and -Linaged vulcanized rublbs /in.2 in elonga- break in elongatioi3 ber product follow in Table IV. mins. aged at iOO% tions of lbs./in.2 per cent 500% Table IV 55 30 0 859 2245 3335 670 120 30 39 872 1915 1940 520 ModuIus of Elasticity Tensile at Ultimate 60 0 1260 3100 4400 660 cure Hour5 at in I lbs./in@2 t 0 onga- break in elongatio inins. aged (0% 60 39 1208 2330 2400 530 3 iOT)s of lbs./in.2 per bentn 90 0 1500 3460 4435 625 go 39 1413 2370 490 - - 30 0 856 2110 3530 685 60 30 39 968 2140 2500 565 125 -From the data set forth in Tible III it is 60 0 1293 3140 4485 6&5 appareiit tlaat the reaction product of di60 39 1420 2785 2890 550 90 0 1513 3450 4305 610 ox)7dinaphthyl-chlorbtitane a;nd alpha-na h90 39 1576 2920 2045 520 p thylam-ine possesses the desirable anti-oxidant 65 properties of the preferred class of comThe data set forfh in Table IV sh6w.s that the 130 pounds set forth herein. preferred class of materials, and specifleal-

4 1)8348,940 I.y, a reactioii prod@uct of dioxy dinaphthylch-lorbutane and para phenetidine coliiprises a,ii iinportant group of anti-oxiclants. The v,ule,,tnized rubber stock wlierein the preforred cll,,tss of materials was incorporate@l prior to tl-ie v-Lileanization tliereof showed remarkably, little depreciation in tensile propeirties -when aoed in the maiiiier described. A further example of the preferred Class of anti-oxidants was prepared by reacting substantially one molecular proporti6n of dioxy-dinaphthyl-trichlorethane 'With an' excess over -,ubstantially eight.n-iolecular proortions of aniline, preferably iD the presence 1.5 OPf@ aniline hydrochloride and- a.small quantity of cuprous chloride, iri a manner anal,ogous to that described above. It is tliought that the reaction representin- the preparatioii of the coinpound d@s(,rib@d proceeds ac20 cording' to the f6llo- wing equation: c-cl3 +8C6H5NH2H 0 H H 0 + 213@-.0 + 3CE[,-,NrI,.Hcl The @roduct thus, prepared was incorporated 30 in a rtibber naix in the usual manner comprising 100, . parts of smoked sheet rubber, 10 parts of zinc oxide, 40 parts of carbon bllck p-,irts of a blended mi@eral oil and ros.111, 35 3.25 parts of sulfur, I : part of diplienyl guinidiiie, part of the anti-oxi(laiit described. The compounded r-Libber stock wos then cured, as in the first menti-Oned examdie, by 40 heating in a press for difterepit erio@ks oT p tiiyie at the tempergttii,e exhibited by fort3T poi,inds 6f sfe@Lm pres ure per square inch. Tiie cured rubber product was the--q aed in t,lie manner set forth for 39 lio-Lirs at a temir, peratiire of 'too C. uiide@r an oxygen -,.essure of 300 pounds per square ii-ich. The teiisile d,,it,,t of t'ile a-ed a,.id tina ed vule,.ii-iizecl rubt, 9 ber product follows in Table V. Table V 10 Ctire ilours MO(lulus of Elasticity t in elongaTensile at Ultima e lbs./in.2 at bfeak in elodgation mins. aged tiors of 300% 6W@@ lbs./i@i.2 per cent 55 '0 0 897 2210 3 210 640 30 39 706 1340 1 730 515 60 0 1445 3300 3 050 51@0 60 3.9 1245 2340 2 565 530 90 0 1640 3670 3 @15 535 go 39 1553 2 615 420 6t) The data set forth in Tab'Le V sliows furtliit the preferrecl class of c6inpounds, th,it is ,t reaction pro(luct o'L --n -,tryl amii-ie a-id ,t c-lioxv-di-@rvlhalogey-i subs@uitutecl p,-trrises a group afi'iiie, com@ of vtluible @.,ubber G5 aiati-oxidalats. As q f tirther exir-tiple of operating the p resent inveiition, a procluct was preparecl by reactir@,,- substantially one molecular proportio@l ol-f clioxv-clipbe-qyl-clilorbutane with stibstclrtially tl@ree ii-iolectilar pi-oportions of ani- 70 li-ne, and this prodtict Nvas compouncled in a rlibb-,r mix comprisiiig 100 parts of smoked sheet rubber, 40 parts of carbo bla k, 10 parts of zinc id,@,(2 7 5 ox parts of a bleiaded inineral oil and rosin, 3.25 parts of sulfur part of dipheii@l gu,,Lnidine, I pal7t of the anti-oxidant described above. The, con-ipoi-inded rubber 911-ock th-Lis f oriiied v%,as etired ii-i tl-ie usual inayiner and I)Ort4onS So of the cured rul.)ber p-- o,-Iuc@u were artifici-ally ,,ged i-T-1 the previously described. it @-?,s fouiid ttia'L- the. cured rubber prodiict, wiierein tl-ic antioxidant clescribed --bove N-,'.ts eiiiployed, shoived increased age res:ist- 85 C (NHC6E[5) 3 c 90 NJ--[ iii.u pi@c)perties over a siini ar stoc w erein I 1 at, acc--Iel@ator -for e--,-ampi-,, diphenyl gtiani95 dii-@-e "7as empl@oyed without iii ,tnti-oyidanL-.. ii-@l lil iii,,i-nner ai-ialogo Lis to thf,,'u hereinbefore -Li'ane, dioxyseL.; oi,th dioxy-dipheiiyl chlorb (I (li-,itrhvthyl triel-iloreth-,t.Tie, @t'Loxy dinapht @ .1 hyl clilorbtit,,i,-.ie aid t:-ie lil-,e iiia3, be, re@ictecl loo )Yitli 'ceiiz;.dine tolidiiie. beta naphthyl ,,tmine licleiie, amin.o dipl@en,,l ,,ncl -@nalogotis a@2om,.ttle ai--qines aiid the procltict tlius obt,,tii-ied eii-i-,@loyed ,is on - @-@iti-ox-idaT-it in a i-tibbc-i- s'(Ccl(.,6f ailetinizacion characteristics. 105 l@-i tll@o e-%--,-)mples he-,rei-ibefo.,@,e s,-,t f,,-rth, (I.,pheiiyl @tliaiiidire iv,-cs empjoye-J is the ae r,,Cller,,itor. bee@iuse it is ITno%vn that a stock iih(.reii.1 it I-, eiiipl("@'C',Cl possesses poor igiiic,,, glities ivhi.eli d @9 ii6t the er,@ect of 110 "I I 0 the ,iT-iti-oxi.cl-,t-Tit eniployecl. in f,,ict, a tread @,,to k of the com- e rloyod iii the exC ri'l I amt,)Ies in the ,)re,-,eiic(- i,,id upcier the infll-,eT-Iee of o-uinicline as an -,ceeleratoi- biit containi@gn,- io 9-@iti-oxicl,,ITlt, melts 115 clo v,7p 'Lo a sh,-,p,-,Iess inpss i-neappble of test iih.-@,i sul )jectecl to t-he -,(Yi-.ig teslu- describecl. Othe ,@-.,,iceelerators coti',.d, of co,,irse, h,-,i,e bee-Ti er.iployecl iiad di-fierent ,T,.odultis ap-c! terisi-le Pligures obt,,tinecl fron-i those, hereinbc, i Or'@' Set 120 fo-utli. but still, exliibi-ti@io, the cl(-sir,,tble age L@ resistiiig properties 6f ti-ie preferrecl class ofcompounds. From the d,,ita lierei.nbefore set f-orth it is 9,ppai,ent tli-,Lt ti)-e pr,-'ierred cl,,),ss of coiii125 poi-i-qds coi-rprises Pii importa-@it cliss of -,tntiY;bieb have beeii eii-ii)!,)yed s'Liecessf-ul@l-t, t,@id ,),eLvanilageoiis"y ill , .7 - t rubbe@@ stoci@. L u -he preseii@ iiive,@ition is limitecl solely I)y the claims attached hereto as a part of the 130