USRE5231E - Improvement in the manufacture of hard flexible rubber - Google Patents

Description

UNITED Sri-HES Aosrrn conny, or NEW Yoeri, n', Y.

WQRVEMNTQIN "rue MANUFACTURE oEVHARoi-"LEXIBLE Russen. f

Specification forming part of Letters latent No. 271,122,- dated'Angust l0, web freies-lleida). 620, dated November To ull whom theyrfooncern;

Be .itflrnown that vI, AUSTIN Gr. DAY, for.-

-merlyof Seymour, in the Stateof Connecticut, but nowot' the city, county., und yStute ot NewL York, here invented el newI and Improved Process or Method of IXVorlri'ng .what are usually denominatedlard-Rubber Coni pounds;

and Ivherebydeclare that ltherollmving is u full, clear, and exact descriptionthereof.

Thenetureof my invention. consists-in ev ner and specicrmode or process of treating: sulphur'nnd Indiurubber or caoutchouc, ory other equivalent or lyulcanizebie gum, in such a manner. as to ,maire `en artificial product whichshnllpossess hardness, and also the properties olindestructibility, exibility, and

elasticity, thereby tting itibrmeny useful purposes in the arts to which no rubber coinpounds which -Werc'known prenions to my invention were adapted.L I y It is well known that Uharies Goodyear, on the 15th of, June, 1845i, patented a process of vulcanizing rubber So as topreserve it soft and fiexible Whenexposed to the summers.

sun or Winters cold, or to l the action 'ot' rarions solvents; and that Nelson-Goodyear, on the 6th otfMey, 1851, patented a process of manui'ac udn a hard-rubber coinpcmnd,77 which he correctly describedinl seid patent as a hard audin-exible substance hithertoy unknown."l -Tho' process of' Charles Goodyear produced what is known inthe arts as vulcanized soft rubber, andthe process of Nelson Goodyear, described in his said, 1.851. patent, produced a vulcanized hard compound; but, as this `hard compound extremely brittle,

and is also incupcblc of receivingr the polish` and finish requisite to adept it -ttc nia-ny pun poses, -it has nevergon'e into use.`

My improvement' was originated ajtcrfthe invention of NclsonGoor your, und is designed l.

asan improvement upon the method devised by bnn of treating rubber combined with sul- .phur or other matters to produce hard compounds; and iti-consists in e specific inode or process of Working India rubber, 'or other equivalent or vulcan irableguxn combined with sulphur, in such u manner as to produce La* compound which sha-ll possess not only all the hardness of the Nelson G-oodyear'productbut v PATENT @einen 9,18158; fextendedsevonyears reissue No. 5,231; datedanuary' 14, 18T?.

render itl `available for f nia-ny purposes in the ertsfy AMy said speoiiic process di'ers from. the process of.' Nelson Goodyear iii-nearly every oneof the various elements of the treatment to which sulphur and Indie rubber, or other vuicanizztble gum, must be subjected ,to pro duce .hardl compounds-that ist-ol say, it'ditfers, iirst, in the proportion oi ingredient-s,` second, in the degree ot" vuicenizing heet to f which these ingredients ere exposed; und,

fina-ily, in the nature und churacterof the re l The Nelson Goodyear proA portions of ingredients are from four toisix .1 -tcen ounces of sulphur to sixteen ounces of rubber, but the 1851 patentstetes that :4better resultwill be obtained from eight@ ounces ci' sulphur und eight ounces of sonic` sulting product.

earthy besemmaguesiu, for example--to sixteen ouncesoi" rubber. My proportions urey f .one part, by Weight, ofsulphur 'to two parte, by

Weight, or' rubber or other vulcanizuble gum,

and no' earthy bese' whatever, for 'although f un earthy base ,might be added., its additionl will not improve the product; .Nelson (lood.-v years vulcanizing heat is prescribed in seid-5 jpatent as 'to commenceA below or at about 2G0O,audter1ninateat about 2750 Felirenhegn My vulcanizing heut is commenced at 275` 3059, and IlQOF-ehrenheit, 'und sometimes higher; the length of,tiu1e the coinpound're,

quires to'bc treated,depending Vgreatly, its is Weil known,` uponthe tempemturek employed".

Moreover, lGroodyeus process merely conteur-i.

plates subjecting his mixture of ingredients `'to ythe 'Vuloanizing heat 'which .he directs for the length of. time which he prescribes, 'Without cny allusion-whatever to the importance of Whatmuy beternied hezttingintervalle5-401,- f

- in other Words, vthe expf'sure ofetheediente` toonc degree of temperature for' a certoininterval of-.,time,' therrto ahigher degreefona certain other'interval', andso. on until the' 0IA eration'is teoinpieted;` Whereas I 4henne found and is always' carried many degrees be? Ayoud.thut'point,frequently reaching to 3000,

2 una t it in certain cases io be well.-nigh indispensable to the production of a desirable result to observe such heating intervals. ".ihenieie statement of these differencesbetween my method and that of Goodyear may seein sul'hcient ,z but their vital importance will be at once manifested whenthe results produced by the two processes are compared. Thus, if

Goodyears mixture be taken at sixteen ounces of sulphur to sixteen ounces ot' rubber, it muy be exposed to the temperature which he direets for any length of time without producing anything but a soft semi-hard or ieathery product, und, of course,- therefore, suoli a mixture so treated is worthless for hard-rubber pnr.

poses; or, it' his preferred nxixture oi' eight `ounces of sulphur and eight ouncesof earthy base to sixteen ounces of rubber be adopted, and be exposed tothe temperature which he directs for the three to six hours which he prescribes, the product Will indeed be hard, but it will also be brittle and utterly destitute of the indispensable qualities of ilexibility and elasticty,ul1ile if it beheated longer than six hours, it will be still more brittle and coniparatively worthless. Finally, it' to sixteen ounces ofrubber and other proportions of suiphur between the extremes ,which Goodyear gives of four to sixteen ounces be selected,

the proportion of ounces of earthy base to the rubber being'increased or diminished. according as such selected portion of sulphur is diminished orv increased, as is directed in .his patent, the results will range, according to tho particular proportions chosen, between the soft or semi-hard product above and the brittle and comparatively Worthless compound ferred to; but by my process the results of merely soft rubber"7 on the one hand, and et hard rubber which is brittle and com zaratively worthless Von the other hand, are alike avoided, and a product is inode which is characterized by the qualities ofivory-likehard ness, accompanied by the spring'temper ot' steel, thereby furnishing precisely the properties whiohvure foundto be essential in the arts, and which are absolutely unknown to the Goodyear compound.

'My invention, in fact, is based upon the chemical discovery wh ich, so iaras I ani aware,

I was the iiijst to announce, that when a rnix.-`

or product'possessing these properties when produced, 'coustitutefniy invention, the said special product forming the subject of separate Lettere Patent of even date herewith.

phur with it in ,the usuai manner, inthe pro portion of about one part, by Weight, ot' sul- `phur to two ports, by weight, rubber or othergum, and, after treating the compound in the way well known to inanuiiicturers for preparing rubber compounds for vulcanica tion, I place the article or articles to be vui canized in a suitable heater-ii preferred, one in which the temperature is equalized in the manner hereinafter describedm-and I then let on the steam or other heat and run the temperature, preferably, directly up to 27T@ Fahrenheit, and fromv that point carry it to 3000, 30.50, or 3100, or even higher, according to circumstances, the time during which the process is to be continued being easily determined by the operator, according to the Inode adopted for applying the heat, and to the grade of result desired tol be produced. I frequently make various changes in the length of time and degree 'of heat employed` at the dierent steps ot' the process to adapt the temperature to diilerent kinds of stock or diii'ei'ent degrees oi'vulcanization, as required for diierent artieies of manufacture. A

It has been found, in the manufacture of hard-rubber and other gum compounds, that ii vnlcaniimtirnL is performed in large heaters it is sometimes dllicult to vulcunizo equally` in every part of the heater. Articles in one portion of the apparatus may be done too niuch or burned, while those of another part may be slack. These imperfections I ani enabled to obriate, when required, by establishing a circulation in the heater which equaiizcs thc teni` peinture in every part of it. This may bc aecoinplished by means oa double-acting pump, or a. lan or other equivalent device, which shall draw out the steam troni one end of the cylinder and transfer the saine into the head of the opposite end, as seen in the drawing, `where A represents the heating-cylinder, supplied with steam for leating` it up under pressure by the tube c, The articles to be vulcanized are placed wit-hin A, The circulation to eqnalize the temperature in all parts is nlado by working the pump B, or its equivalent, which` draws the steam from the C end oi.' the heater, through valve a, and foi-,ces it through valve b, and thence through pipe D, whence it strikes against head1?, and is distributed through the perforated p intofll, and so through the body oi the cylinden lt is evident that a sin gleucting pump, or a double-acting punip, or a rotary pump, or a 'forcing and exhausting fan, may -bc used ior this purpose.

I do not now claim any special forni of appa,- ratus, for a variety of known apparatus might be used to accomplish the ellect. Even a cur rent ot' steam forced in at one end and out at tbe, other would. else aid in keeping up the cirenlnon and tend 'to equalize the beat., but very impereetlj'. The novelty consists n the making an mtifelal ereulntoz'l in a Vulcanzing zngznaiitns9 irrespective of tbe special means employed fon hnl". purpose.

I (le not Chinn, in the broad, vnlcanizjng Sulphur nml rubber e1' Othelequvalent gums, irrespective ef the special process need and the eelnl product milde; out

I eleln. ns my l'n'enten, and desire te secure by Letters. lntent. i"

II. The herendeecribed special process of producing vulcanized 11a-rd compounds which possess the properties vof exibility and elasticity, set forth, by vnlcanizing in any suitA able apparatus' :L mixture composed of two.

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