CA1205511A

CA1205511A - Fuser member

Info

Publication number: CA1205511A
Application number: CA000413942A
Authority: CA
Inventors: James S. Newkirk; Robert A. Wiederhold
Original assignee: Eastman Kodak Co
Current assignee: NexPress Solutions LLC
Priority date: 1981-10-22
Filing date: 1982-10-21
Publication date: 1986-06-03
Also published as: US4430406A

Abstract

FUSER MEMBER
ABSTRACT OF THE DISCLOSURE
A fuser member has a composite layer including (1) a first layer of a first material which is an elastomer; (2) a second layer of a second material which is preferably a fluoroelastomer which is impervious to fuser oil absorbed by said first material; and (3) a layer intermediate to and continuous with the first and second layers in which the proportion of the first material to the second material gradually varies from substantially only the first material to substantially only the second material.
Methods of making the fuser member by a spray technique and of using the fuser member to fuse toner images to a receiver are also disclosed.

Description

~LZV5Si~

FUSER MEMBER
BACKGROU~D OF THE INVENTION
_ Thi6 inventlon relate6 generally to the field of eleetrogr~phy ~nd ~ore particularly, this 5 ~nventlon relate6 to the fu6ing of toner i~ge~ ~o receiver6 by means of heat and pre66ure.
In the field of electrogr~phy, ~6 pr~c-ticed, for ex~mple, in commercisl copier~, B radi~-tion ima~e of sn original to be reproduced i6 projected upon ~ uniformly chsrged pho~oconductive member to produce a latent electro6tatic lmage corre~ponding to the original image. A vi6ible toner im~ge i~ produced by dev~loping the electro-6tatic im~ge with ch~rged toner p~rticle6. If the photoconductive member 16 reu6able in the form of ~
belt or drum, the toner ~mage ~6 then er~n6ferred to a receiver 6uch a6 ~ web or ~heet of plain p~per ~nd fu6ed to the receiver. If the photoconductive ~em-ber lt~elf i6 the receiver, then the toner lm~e i6 20fu6ed directly to the mem~er.
One technique which ~y be u6ed to fu6e ~
toner image to ~ receiver i6 through the Applicatlon of heat snd pre~6ure by ront~cting the toner im8ge with a heated fuser member 6uch a6 ~ roller or 2sbelt. Commonly~ a pflir of roller6 held together under pre~ure form a nip through which a toner lmage carrying receiver 16 ps6sed. One or both of the roller6 sre hested to melt the heat 60ftenable toner partlcle6 to fu6e the toner image to the 3~receiver .
In such fu~ers, one or both roller6 preferably include ~n el~6tomeric layer to lengthen the nip through wh~ch the toner image p~6ses ln order to increa6e fu6ing time and to lower fu~i~g 3senergy requirement6. The el~6tomer~c layer ~hould be re~i6tsnt to degrad~tion at high temper~ture6 . .~

si~

-2 over a long oper~tlng life. In ~dd~tlon, ~he ~ursce of the fu6er roller conte~elng the tonRr image 6hould be of ~ material havlng good rele~6e ch~rActeristic6 to prevent off~e~ of ~oner partlcle6 5 onto the 6urf~ce of the fuser roller ~nd to obvi~te the tendency of the copy 6heet to wr~p around one of the roller~ cau6in~ copier malfunction. Although 6ilicone el~stomer6 and fluoroelastomer6 exhibl~
good resistance ~o degrsd~tion ~t hi~h tempersture6 well a6 good relea6e ch~racteri6tics~ it h~6 been found necesssry to apply ~ coating ~f fu~er oil to the fu~er roller in order eO eliminate any po~sibility of offset to ~he roller of cont~mln~nt6 6uch a6 toner~ paper p~rticle6 ~ etc . Thu~ riou6 fu~er 0116 6uch 86 fluorocarbon oil65 6ilicone oll~
and fluoro6ilicone oll~ mfly be spplied to the fuser roller to improve itE toner off6et preventing chArsc~ceri6tlc ~ .
Addition~lly, $n commercl~l electrogr~phic 20copier6 which proce66 6ever~1 thou6~nd copy ~heet6 per hour, it i6 highly de6ir~ble that the fu6er be capable of operflting over B long life ~o th~t the operstion of the machlne i~ no~ ineerrupted by fu6er p~per ~ms or replacement of ~ defective fu6er 2scomponent. Fu6er6 including Q silicone el~Gtomer roller to whlch 6il~cone fu6er oil i6 ~pplied in combin~tion with a fluoropolymer~co~ted ~et~llic pre~6ure roller have ~ucceeded in min~m~zing psper ~ams cau~ed by toner ofse~ and in increfl6~ng the 30oper~ting life o the fu6er. Over ~ perlod o time~
however, the ~illcone fu~er o~l tend~ to be ~b60rbed lnto the 6ilicone elfl6tomer c~u6ing lt to 6well.
~hi~ ~well may c~u~e the growth of a ~tep pattern in the roller ~f copy sheet~ of a v~riety of length6 3s~re proces~ed by the copier. The6e 6tep6 sre formed by gre~ter 6well1ng due to fu~er o~l ~bsorption ~Z0~5 beyond the area6 of the roller u6ed to proce66 the 6horter length cop~e6. When longes length copie~
are pa~6ed thr~ugh the n~p of ehe roller fuser, uneven fusing c~u6e6 $mage deterior~tlon in the 5 proce6~ed copy 6heet and t~mage eo the ~heet. S~nce im~ge deterioration 16 unde6irable~ the roller fu6er member m~y have to be replaced neces~lteting ~
6ervice call and incap~citatlng ~he copier for 6ever~1 hour6 with ~ttendant ~nconvenience, fru6tration and eo6t. Step growth pattern in el~6tomeric fuser rollers ha6 been found to be especi~lly per6i~tent when both fu6er roller member~
~re provided with ela6tomeric layer~ ~ when proce66ing c~py 6heet6 with unfused toner im~ge~ on both 6ide6 of ~he 6heet~
Swelling of the 6ilicone el~tomer~c lsyer by ~b60rption of ~ilicone fu6er oil may be mlnimized by providing ~ multi-l~yer fu~er member wherein the 6ilicone ela6tomeric layer i6 overcoated wlth A
201ayer of material which i6 re~i6tent to sb60rption of 6illcone fu~er oil. Such silicone oll re6i6t~n~
m~terial6 ~nclude the fluoroel26tomer6 æuch a6 fluoro~llicone el~tomer ~nd fluoropolymer-ba6ed ela6eomer6 6uch 8~ v~r~ous vinylidene fluoride-bs6ed 2sel~s~omers which contain hexafluoropropylene ~6 comonomer, or example, Viton~ A (vinylidene fluoride-hexafluoropropylene) and VitonB
(vinylldene fluoride-hexsfluoropropylene-tetra1uoroethylene3 which are 30svailable from the Dupont Company. Viton~
trademsrk of DuPont. Such msterial~ ~re 6ubst~n-t$~11y more re6i6tent to 6ilicone fu6er o~l ~b~orption than 6ilicone el~stomer and sub~tanti~lly decre~6e the formlng of ~tep~ in the 611icone 3sela~tomeric underlayer. In order to in~re~6e the relea6e ch~raeteri6tic~ of ehe fu6er roller, a th~n ii5~
,, coating of 6ilicone el~6tomer ~y be applied to the fluoroela6tomer to form ~ ~hree-l~yered fu6er ~ember.
Although the ~forementioned ~ultilayer fu6er roller~ have been found to ~fn~mize the for-5 mation of 6tep~ and con6equent lmage degrads~on ~nprocessed copy ~hee~, thereby 6ub6tsnti~11y increa6in~ the life of the fu6er roller, le ha6 been found difficult to form the multi-layered fu6er ~embers due to the difficulty ln edhering fluoro-ela6tomer~ to 6ilicone ela6tomer~. ThUB, ~ fu6er roller having a ~ilicone ele6tomer ba6e l~yer to which i6 adhered a fluoroela6tomer layer h26 been found to exhibit 6eparation between the layer6 with prolonged u6e. Thi~ 6eparation may be accounted for by the lack of Affinity of the fluoroela6tomer~ for other materisl~ and by the constant flexing of ehe fuser roller during u6e.
As ~ con~equence of the foregoing problem6 s660cisted with known fu6er member6, ~he ~eed hB6 20been present for 8 fu6er member to whlch fu6er oll may be applied without ~welling of the ~ember snd re6ultant ~tep format$on therein. The member ~hould have a long operating life and be ~ble to f~nction at high fu6ing temperatureE withoue 6tructural 2sfailure. A multilayered fu6er roller sho~ld not have interlsyer ~eparation over it6 u6eful life.
SUMMA~Y OF THE INVENTION
In accordsnce wlth the pre6ent inventlon 9 there i6 provided an improved fu6er ~ember and 30method of meking ~nd u~ing ~uch member which ~
re~l~tent to the formation of 6tep6 in the surf~ce of the member eau6ed by the ~b60rptlon of fu6er oll applied to it. The fu6er member l~ provided with long life cspable of proce66~ng 6everal hundred 35thou~and copy 6heet6 without ~ noticeable deterioration ln the ~mage quality of fu6ed ~mage6 and wlthout dsm~ge eO the 6heet~.
According to one ~6pect of the invention, n method of forming a member for fu6ing ~oner ~mAge6 ~0 B receiver i6 provided in which ~ ba6e member ~6 5 6prayed with a fir~t ~a~eri~l ~hich 1~ ~n ela6tomer. After ~ layer of ehe fir~t ma~erial i6 $ormed, the fir6t materi~l i6 continued to be ~prayed while 6prsying a gradually lncreR~ing proportion of a 6econd material with the fir~t ma~erial until only the ~econd materisl 16 6prayed.
SprPying of the 6econd materi~l 16 eheresfter contlnued to form a layer of only the ~econd materisl. Preferably both ~he flr~t ~nd 6econd ma~erial6 ~re high-temperature re6i6tent ela~tomer6 ~and the 6econd material ~ re616t~nt to sb~orpeion of fu6er oil to ~ct ~6 a b~rrier to ~b60rption of fu6er oil by the fir~t material.
According to another ~6pect ~f the invention, ~ fu~er member i6 provided which ha6 a 2ocompo6ite layer including (1) ~ fir~t l~yer of 8 flr6t material which i6 ~n ela6tomer; (2) 8 cecond layer of a 6econd materisl diferent from the fir6t materi~l; and (3) a layer intermediate to ~nd contlnuou6 wlth the fir6t ~nd second layere ~n which 25the proportion of the fir6t ~aterial to the second msterial gradually varie6 from ~ub~t~ntially only the fir~t material to 6ub~tsntially only the 6econd material. Preer~bly both the fir6t nnd 6ecoad materiAl6 are high-tempersture re6i6tant ela~omer6 30and the ~econd materi~l i6 re~istAnt to ab~orptlsn of fu6er oil to prevent ~bso~ption of fu~er oll by the first materl~l. According to snother a~pect of the lnvention the fuser member compri6e~ ~ u6er roller having ~ composite l~yer a~ descrlbed ~bove.

SSll Another s6pect of ~he invention pro~de& a method for fu6ing toner lmage~ to ~ receiver by cont~cting a toner image wi~h ~ fu~er member ~Aving a compo6iee layer ~6 de6cribed above.
The inventlon ~nd ~t6 feature~ ~nd sdv~n-t~ges will be 6et forth ~nd become more app~rent in the detAiled descriptlon of the preferred embodimen~
pre~e~ted below.
BRIEF DESCRIPT10~ OF THE DRAWINGS
In the de~ailed de~cription of the preferred embodiment of the invention pre6en~ed below, reference i6 made to the accompanied drswing~
in which Fig. 1 i~ one embodiment of ~ fu6er roller member according to the pre6ent lnvention;
Fig. 2 i6 another embodiment of ~ fu6er roller member according to the pre6ent invention;
Fig. 3 6how6 the fu6er member of Fig. 2 a6 used ln a roller fu~er for fixing 6implex im~ge~;
Fig. 4 i6 an app2ratu6 which m&y be u~ed in effectin~ the method of ~he present lnventlon;
Fig. 5 i6 another embodiment of the fu~er member of the pre6ent invention; and Fig. 6 i6 B fu6er roller incorporating two 2sfu~er member6 accordlng to the embodiment of Fig. 2 in fixing duplex images ~o a receiver.
DESCRIPTION OF THE PREFERRED EMBODIMEN~S
_ According to ~he pre~ent invention, ~ulti-layer fu6er member6 of different configuration6 ~ay 3Cb~ provided. For example, the u6er member l!Day compri6e 9 flat pl~te, a belt, or ~ roller.
However, ~n commercial elec~rophotographic copier6, the mo~t common configurstion of fu6er ~ember i6 a roller. Accordingly 9 the embodiment ~hown ln Fig ~ 1 3sinclude~ a fu~er roller 10 wh~ch m~y be heated internally~ Roller 10 include6 ~ core 12 of heat ~21~51~

conductive materisl 6uch ~6 ~luminum, br~6 or htsinle~ 6teel or heat tr~n~mi6~ive msteri~ ch a~ glas6. A compo6ite l~yer bonded to core 12 ~nclude~ l~yer~ 14 ~nd 16 of el~6tomerlc ~steri~læ
5 which are re~i6tant to degr~d~tion ~t h~gh tempera~ure~, e.g. in the r~nge of 100C to 200C. According to one embodiment of the pre6ent invention, the materi~l of l~yer 14 i6 ~
poly~iloxane els~tomer ~uch a6 6ilicone els6tomer.
lOThe maeerial of layer 16 i~ prefer~bly an ela6tomer which reslst6 ~b~orption of ~ilicone fu6er oll ~nd may, for exemple, compr~6e ~ fluoroela6tomer 6uch ~6 fluoro- 6~1icone or a fluoropolymeric ela~tomer such a6 the vlnylidene-fluoride ba~ed fluoropolymer~.
According to the pre6ent lnvention9 a layer 15 i6 intermedl~te to snd continuou6 with l~yers 14 and 16 snd compri6e~ ~ ~r~dually v~rying ~lxture from only the materisl of l~yer 14 to only ehe material of layer 16. Layer 14 mfly be previou61y 20formed on core 12 by known eechnlque6 6uch ~G
molding, before ~pplication of lsyer 16 or l~yer 14 m~y be formed during the proce~s ln which layer 16 i~ formedO Where ~ thickne6~ of l~yer 14 ha6 ~lre~dy been formed on core 12, preferably a thin 2scoating of the 6sme ela6tomer A6 lByer 14 i~
in~ti~lly 6prayed ~nto layer 14 to form 8 continuou6 lsyer therewith. While the msterisl of l~yer 14 i6 continued to be 6prayed, the msteriRl which ~6 to form leyer 16 i6 ~imultsneously ~prayed in gr~du~lly 30vsrying proportion wlth the layer 14 msterisl~ A6 6praying continue~, the proportion of ~he layer 14 m~ter~l decre~6e6 while the proportlon of l~yer 16 m~teri~l increa6es until only the l~yer 16 m~terl~l 16 being 6pr~yed. Only th~ material 16 then 3s6pr~yed to the de~red thickne66 of lsyer 16.
Altern~t~vely, the leyer 14 material m~y be 6pr~yed ~2~

directly upon core 12 and a desirable thicknes6 thereof built up before the formation of l~yer 15 i6 initiated.
The gradually varying layer 15 formed 5 between layers 14 and 16 may be effected in ~everal ways. In one method, the propor~ion of the layer 14 material and the layer 16 material being sprayed ls continuously changed ~o that initiAlly only layer 14 elastomer is sprayed and finally only 1 yer 16 10 elastomer is being sprayed with the propor~ion of the two materi~ls continuously varying during the spraying process 60 that the proportion of the layer 16 material to layer 14 material gradually increases, In another method, the proportions ~re 15 changed in fixed steps 80 that, for example 9 inltially only layer 14 elastomPr i8 sprayedg then say, a mixture of 75% of layer 14 elastomer and 25%
of layer 16 elastomer is 6prayed; then a mixture of 50% of each elastomer is 6prayed; then a mixture of 20 25% of layer 14 elastomer and 75% of layer 16 el~stomer is sprayed; and then only layer 16 elastomer is sprayed. Other variatlons in the proportions of materials and number of layers may be effected within the æcope of the present invention.
The layer 14 elastomer and layer 16 elnstomer are preferably dissolved in the ~ame solvents or solvent6 or ~nsolvents in which both elastomers are soluble prior to spraying in order to maximize compatability of the material6 once spr~yed 30 on the roller. The 601vents u6ed are preferably a suitable mixture of low boiling point and high boiling point 601vents, the ratio of one æolvent to another being selected to obtaln proper drying time to insure acceptable roller properties 6uch as the 35 ability to resist delamination between layers.

~2~5~1~
g In the embodiment of ~Fig. 2, a ehird l~yer lB of toner off6et preventing els6tomer 16 prov~ded which cont~ct6 a toner ima~e c~rried by 8 rece~Yero A layer 17 iE intermedia~e to ~nd continuous w~h 5 l~yer6 16 ~nd 18 ~nd compri~e6 e gradually v~rying proportion of the layer 16 el~stomer snd ehe layer 18 ela~tomer from 6ub6tanti~11y only the layer 16 ela6tomer to 6ub6tantl~11y only the l~yer 18 el~6~
tomer. ~he el~tomer of layer 18 i6 prefer~bly the ~ me s6 the el~stomer of leyer 14 ~nd m~y, for ex~mple, compri6e ~ilicone el~6tomer. L~yer 16 i6 preferably of fu~er oil re~i6t~nt ela6tomer 6uch as fluoroela~tomer ~nd 6ub6t~ntially prevent~ ~ny o~l ab60rbed by l~yer 18 from penetrating to lcyer 14 lSand thereby 6welllng it.
Referring now to Fig. 3, there i~ 6hown ~
fu~er roller ~ccording to the embodiment of Fig. 2 incorpor~ted into ~ roller fu6er u6ed ln ~n electro-gr~phic copier for fu~ing receiver6 c~rrying toner 20image~ on one ~ide thereof. A~ 6hown, roller 30 includes ~ met~llic core 3~; ~ fir~t layer ~4 of high~temper~ture re~i6tant 6ilicone ela6tomer bonded thereto; ~ 6econd l~yer 36 of ela6tomer which ~6 impervious to 6ilicone fu6er oil snd re~i6t~nt to 2sdegr~dstion ~t high tempersture6 ~uch ~6 fluoro6ilicone or a fluoropGlymeric ela6tomer ~uch s6 the vinylldene-fluoride b~6d fluoropolymeric ela6tomer~; ~nd d layer 35 intermedint~ to snd cont~nuou6 with layers 34 and 36 ~n which the 30proportion of the ~llicone ¢ls~tomer to the fluoroela6tomer grsdually varie6 rom sub6tantially only the 6ilicone ela~tomer to ~ub~tantlfllly only the fluoroelsstomer. A third l~yer 38 i6 provided which m~y be ~ny high temperature re6i6tant ~Ateri~l 35which has ~ood toner off6et preventing oh~racter~ ~tis:~ . Preferably lnyer 38 i6 of the same ~;~@~S5i 1~

~lo-material a~ layer 34 ~nd therefore ~ay co~prl6e 6ilicone el~stomer. However, thl6 ~teri~l ~ay ~e ~ny other hi~h temperature resl~t~nt el~omer vhlc~
~how6 ~ood ~oner off6et preventlng chRraceeri6ticc 5 or ~By be a flexible polymer ~h~ch i6 noe el~6tomerlc but which ha~ good toner of~et preventlng cheracteri~tic~ ~nd which 16 he~t re~i6-tent, ~uch ~s the fluoropolymer which cGmpr~6e6 ~
copolymer ~f tetrsfluoroethylene and polypropylene.
1~ L~yer 37 ~6 intermediste ~o and contlnuou~
w~eh layer6 36 snd 3B ln which the proportion of the lsyer 36 maeerial ~o the layer 38 ~sterial ~sadually vsrie~ from ~ub6~anei~11y only the lAyer 36 ~eterisl to ~ub6t~ntially only the layer 38 ~terl~l.
In order to enhance the toner off6et preventing charscteri6tic6 of the curface of lsyer

3~, fu6er oil i~ ~pplied by ~e~n6 of a wick 40 held again6t r~ller ~0 by member 42. ~ick 40 16 ~atursted with fu~er o~l cone~ined ln ~ump 44. A
201~rge number of known fu~er ~ are commerclally avallsble and ~ultsble for such u6e. For ex~mple9 a 6erle6 o ~ilicone glycol copolymer liquids ~6 well a6 ~n alky1Aryl 6il~cone liquid, ~ chloro-phenylmethyl silicone liguid, a dimethyl cilicone 2s1iquid ~nd ~ fluoro6i1icone liquld are commerc~lly av~1able from Dow Cornlng Compnny. Additlcnnl u6eful materi~l6 would include polyvinyl$dene fluoride liquid6, pol~oonochlorotrifluoroethylene llquid6, hexsfluoropropylene viny1idene ~luoride 30copolymer6, perfluoroalkyl polyether~, fluoroalkyl esters, block copolymers of cli.methyl siloxane with a variety of materials such as Bisphenol A, tetramethylspirobi(indan)diol and the like.
Of course, other fuser agents exhibiting good 5S~

therm~1 6tsbility ~re ~l~o u~eful. Obviou~ly, ~n 6electing an off6et-preventlng liquid, csre should be t~ken to 6elect a l~quid which ~6 ~hem~c~lly comp~tible with the toner off~et preventing layer on which it i~ 8ppliedO
A pre~sure roller 50 16 held ln pre6~ure engagement w~th fu6er roller 30 by 6uitable force-~pplying me~n6 6uch ~ thst di6clo6ed ~n Re6eareh Di6clo~ure N~. 13~703, Sept. 1975, publi~hed by lndustri~l Opp~rtunitie~, Ltd., Homewell, Hav~nt, H~mp6hire, UK. Pre~sure roller 50 ~nclude6 ~ core 52 of me~&llic materi~l mounted on Ehaft 54 ~nd ~n outer l~yer 56 of materlal having good toner ofi6ee preventing ch~racteri6tie~ ~uch a~ polytetr~-fluoroethylene, ~ilicone el~tomer or fluoroelas~omers ~uch n6 the vinylidene-fluoride b~6ed fluoropolymeric el~6tomer6. Roller~ 50 snd 30 form ~ nip through which i6 p~s~ed rece~ver 58 c~rrying an unfixed toner im~ge 60 on it6 under61de. Through hest snd pre6~ure, toner i2~ge 60 i6 fixed perm~nently to receiver 58 ~6 it p~66e6 th~6 nip. Due to the toner off~ee preventing propertie6 of l~yer6 56 snd 38, any fuser oil ~pplied to l~yer 38 by wick 40~ roller6 30 ~nd 50 wlll not be cont~min~ted by toner from receiver 58 ~nd eopy 6heet 58 will exit the roller nip without 6ticking to either of these roller6. Thu6, ~am6 snd fu6er m~lfunction ~re obvi~ted.
The line~l pre~ure between roller6 30 ~nd 50 ~y v~ry, but typicAlly ~6 within the r~nge from ~bout 0.05 to ~bout 4 kllogr~m6 per centimeter of roller length. The temper~eure m~lntained in the oip which 6erve~ ~6 the he~e fixing zone of the roller fu6er i6 generAlly withln the rsnge of rom About 110~ to abou~ 2~0C. The eemper~ture cho~en 16 ~ functlon of the softenlng temperseure of ~ 5 S~'~

the toner powder, the rate at wh~ch the recelver material carrying the toner powder ~m~ge ~ p~6Eed through the nip of the fu~er roller, the length of the nip, and the force of roller engagement~
To further enh~nce the variou~ proper~ie~
of fu6er roller 30, lt may be u~eful in certain ~ituations to provide vAriou6 flller6 to urther enhance thermal propertie~, mechsn~cal 6treng~h, or toner off6et preven~ing propereie6 of the outer lsyer of the fuser member~ Typically, the thick ela~tomeric layer 32 may cont~in varlou~ filler~
~uch a~ carbon black or 611ica for 6trength and variou~ metal oxides, metal part1cle~ or ~he l~ke to enhance the thermal conductivity of the ela~tomeric material. In addl~loD~ vsrlou6 pla6ticizer6 or the like msy be u6ed where ~ece6~ry or where de~irsble.
Although fu6er roller 30 o Flg. 3 i~ shown a6 ~ncluding an internsl he~ting 60urce ~uch ~6 20qusrtz lamp 62, other internal heRtlng source6 msy be provlded ~uch a6 a heated liquid or a re6i6tance elemen~ located wi~hin the roller core. In the slternative, sn extern~l 60urce of thermal energy may be provided to heat the 6urface of fu6er roller 2S30 .
Referring now to Fig. 4~ there ls shown app~rstu6 which 16 u6eful for carrying out the method of the pre6ent lnvention ln ormlng u~er roller6. A6 ~hown, ~ fu~er roller 70 to be ~prsyed 30according to the methot of the pre6ent inventlon i6 rotatably mounted in bearln&6 72 ~nd 74 by gudgeon6 71 And 73 re6pec~ively. A mo~or 76 i~ connected to roller 70 to rot~te it ~t a predeter~ined rot~tlon~l ~peed. Spray a66embly 78 i6 provided and includes a 3Scarriage 80 upon which are mounted spray head6 82 ~nd 84. C~rriage 80 i6 driven for movement ln dlrections 86 by mefin6 of 6crew thread 88 rot~t~bly mounted ln bearing6 90 ~nd 92 hnd driven by ~otor 93. The spr~y ares of ~pray head~ 82 ~nd B4 ~re contiguou~. Spray head 84 i6 6upplied with flrst 5 mAteriRl to be 6prayed from re~ervoir 95 by oean6 of flexible conduit 94. In like msnner, 6prsy he~d 82 i6 6upplied wlth 6econd materisl to be sprayed ~rom reservoir 96 by mean~ of flexible conduit 98.
Valves 100 and 102 in conduit6 94 and 98 re~pectively control ~he amount of msteri~l 6upplied to 6pray head~ 84 and 82. A ~ource 104 of pre~6uri~ed fluid 6uch ~6 ~ir provlde6 pre66ure to drive fluid motor6 76 and 93 to prov~de ~ pneumatlc source for oepraying m~ter~ al~ from 6pr~y he~d~ 84 and 82 ~nd tv provide pres~ure to re6ervoir~ 95 and 96. Conduit~ 100 and 101 having regulstor6 102 ~nd 103 6upply pre6~urlzed ~lr to re~ervoir6 95 anB 96 re6pect~vely. Condu~t6 106 ~nd 108 6upply pre6surized air to spray he~d~ 84 and 82 20re6pectively. V&lve6 110 and 112 control the amount of sir ~upplied over conduit6 106 and 108 re6pectively; while valve6 114 snd 116 control the actuation of 6pray head6 B4 ~nd 82.
Following is ~ de6cription of the format~on 2sof a fu6er roller 70 accordlng to the ~ethod of the pre6ent invention u6ing the ~pp~ratu6 of Fig. 4.
The ~praying operation $6 carried out ~t ~mbient temperature but both temperature ~nd hum~dity are preferably con~rolled to avold extreme~ of e~ther or 30both. Fu6er roller 70 will be ~6~umed to have ~
final 6tructure in accordsnce with the multi~l~yer roller 6hown in Fig. 2. In such c~6e, the fu6er roller may eompri6e fir6~ and third layer6 ~f silicone ela6tomer and a 6econd l~yer of a 3sfluoroela~tomer 6uch the eerpoly~er of vl~ylld~ne fluoride, hexafluoropropylene and -~4-tetr&fluoroethylene ~old under the n~me of Vlton~
B, a trademark of the DuPont Company. The latter material is highly ~mpervious to silicone fuser oil and is resistant to degradation while operating at 5 high temperatures in the range of 100-200C. Silicone ela6tomer ~ o highly resi6tene to deterloratlon B~ high operatin~ temperature6 but exhiblt6 B
greater tendency to ab~orb 611~cone fu6er oil6 thu6 cau~ing unde6irable ~ell~ng and ~ormat~on of tepllke pattern6 over prolon&ed u6e. Thu6, the fir6t layer i6 formed of 6il~cone ela6tomer ~nd provide6 the thicke6t lAyer of ~he ~ultilayer fu~er roller. The third l~yer ln contact with a eo~er lma~e ~6 of 611icone els~tomer 61nce 6~11cone lsgener~lly ha~ beteer off~et preven~ng chærecteri6t~c6 than v~nylidene fluoride b~6ed fluoroela6to~er. The 6econd l~yer of fluorcela6eomer pro~ide~ ~ bsrrier layer ~o prevent ab60rption of fu6er oll by the fir6t elss~omer layer.
Re6ervolr~ 95 ~nd 96 6hould contsin 6ufficlent quantitie6 of ~ cone els6tomer ~nd fluoroela6eomer 60 ~hat fu6er roller 70 ~ay be formed wlthou~ repleni~hment ~f reservolr6 95 ~nd 96 durlng ~he spraying proce~6. Where seversl fu6er 2sroller~ ~re to be made in 6ucce66ion~ the c~pacity of re6ervo~r~ 95 ~nd 96 ~hould be gre~t enough ~o th~t they need be repleni6hed le66 frequently ln order to ~Gint~in productlvley.
An exempls~y fu6er roller 30 ~ayp for 30ex~mple, include a core 32 of ~luminum h~ving ~n oue6ide di~meter of three Inche6. ~ fir6e layer of ~llcone ela6tomer of orty to eighty tpou6~ndth~ af ~n inch thickne66 i6 lniti~lly applied to the core.
~ 6econd layer of fluoroeln6tomer ~aterl51 which 16 35re~16tent to 611icone fu~er oll ~nd which ~
- ~pproximately two to ~ive thou~ndth6 of a~ ~nch .~ r~
`~"~, ;f,~

5Sl~

thick i6 6ubsequently ~pr~yed on the 6illcone el~tomer lsyer according to the method of the pre6ent ~nvention. A thfrd l~yer of ten to twenty thou6sndth6 of ~n inch of 6ilicone el~6tomer ~6 then 5 appl~ed to the fluoroelatomer layer by ~ean6 of ehe method of the pre6ent invenelon.
A fuser roller i6 ormed by the ~pp~ratu~
of Fig. 4 ~s follow~:
An aluminum cylinder 70 which ~y be pretreated to promote adhe~ion of the 6ilicone el~stomer i6 rotatably mounted ~n bearing6 72 and 74 by me~n~ of gudgeon6 71 ~nd 73. Moeor 76 i~
connected to gudgeon 73 ~nd c~u~e6 cylinder 70 to rot~te ~t a predetermined velocity. Si~uleaneou~ly, lSmotor 94 c~u6e6 6prBy hesd6 84 ~nd 82 cArrled by carr~ age 80 eO move back and forth ~cro66 cylioder 70 a6 it i~ rot~ted by motor 76. The rotstional veloclty of roller 70 ~nd velocity of carrlsge 80 ~re ~ynchronized to effect the de~ired buildup of 2olcyer6 on roller 70. L~yer buildup i6 ~180 ~
function of the rate of ~prsying by 6pray he~d6 84 ~nd 82 ~nd of the chsracteri6tic6 of materi~l6 being 6prayed.
~6 roller core 70 i6 rot~ted ~nd c~rrisge 2580 i6 cau6ed t~ move back and forth ~cro66 the width of roller 70, 6ilicone eln6tomer i6 6prayed upon core 70 to build up the $ir6t l~yer to the de~ired thickne66 of, e.g. forty thou~andth6 of ~n loch.
Since 6praying technique6 ~ight require en 30unneces6~rlly long time for building up cuch a thickne66, ~t m~y be desir~ble to provide a core 70 upon which ~ lsyer of silicone el~6tomer hs~ ~lready been ormed by other technique6 6uch ~18 moldirlg.
Then, only ~n ~nitisl t:hin l~yer of ~ilicone 3sel~6tomer need be sppïied over thi~ l~yer ~o thst the time required for ~pr~ying i~ 6ubstanti~11y -1~6-reduced or ~ mixture of 6ilicone el~6tomer and fluoroel~stomer m~y be 6prsyed lmmed~tely on the Gilicone layer, After the de~ired thickne~6 of slllcone 5 el~tomer ha~ been 6pr~yed onto core 70, 6illcone ela6tomer i~ continued to be ~pr~yed upon roller 70, valve 116 i6 gr~dually opened to ~ctuate 6pr~y he~d 82. V~lve 114 which hs~ been fully opened during spraying of s~licone ela6tomer only by head ~4 i6 now gradually clo~ed ~ vfllve 116 i6 gr~dually opened 60 that the mixture of the ~ilicone elastomer ~nd fluoroela6tomer 6pr~yed by he~d6 ~4 snd 82 will gr~duslly vary from only ~illcone elsstomer be~ng 6prayed to only fluoroela6tomer being ~pr~yed. When only fluoroel~6tomer ~6 being ~pr~yed, v~lve 114 wlll h~ve been closed, v~lve 116 will be ully opened, ~nd fluoroelafitomer will continue to be sprayed unt~l the de6ired ehickne66 of the floroela~omer layer i6 built up.
2~ To build up ~n outer l~yer of 6ilicone ela6tomer, the rever~e proce66 is now effected. A6 fluoroela~tomer i~ eontinued to be 6prsyed upon roller 70 6ilicone ela~tomer 16 progre~ively Added to the 6prsy mixture until only 6illcone ela6tomer 2si6 bein~ ~pr~yed to ~ desired thlckne~s. The multilayer fu6er roller $~ then re~oved from the 6prsying ~pp~ratu6 snd cured by known curing technique~ e6 will be more fully evident to thoGe ~killed $n the ert rom the herelnafeer de6cribed 30example.
Referring now to Flg. 5, there i~ ~hown snother embodiment of the preseDt invention. ~
6hown, a belt 120 i6 di6po~ed ~bout roller6 122 ~nd 124 for movement ~n the direction of ~rrow 126.
35Belt 120 compri6e6 ~ 6uppor~ l~yer 128 of heat conductive mater~sl ~uch R8 metal. Upon layer 128 5~

16 bonded heat conductive ela~tomer~c l~yer 130 of 6uitsble m~terial 6uch 86 6ilicone el~6tomer. Al60 provlded ~re outer l~yer 132 of fu6er cil-imperviou6 ela~tomer ~uch ~ a vinylidene fluoride b~6ed 5 ela~tomer Vi~on- ~nd l~yer 131 intermedi~te Eo and continuou6 with layer6 130 ~nd 132 ln ~hich the proportion of the 6ilicone ela6tomer to the fu~er-oll imperviou6 ela6tomer gr~du~lly v~rie~ from ~ubst&ntially only 6~11cone el~6tomer to 106ubstantially only oil ~mperviou~ ela6to~er-Po~itioned w~thin roller 122 i6 a 60urce of hea~
6uch a6 quartz tube 134. A pre66ure roller 136 hs6 a core 13~ &nd ~n outer l~yer 140 of toner of6et preventlng ~ter~sl 6uch a6 polytetr~-fluoroethylene~ A wlcking a~6embly 142 ~pplieæ
fu6er oil to the outer ~urf~ce of layer 132 to prevent off6etting of toner particle6 rom proce~6ed receiver~ onto bel~ 120. In oper~tion, ~ receiver 58 c~rrying a toner im~ge 60 on it~ lower 6ide i6 20moved through the nip between pre~6ure roller 36 ~nd hea~ed fu6er belt 120 eo permanently flx im~ge 60 to receiver 580 Referring now to Fig. 6, there i6 ~hown ~nother embodiment of the pre~ent invention whereln 2sduplex im~ge~ on a copy sheet ~re flxed by ~ pair of fu6er roller6 made sccording to the preæent invention. A6 shown, a roller fuæer 150 include palr of identical roller6 made ~ccordlng to the embodiment of Fig. 2. Vpper fu6er roller 152 30include6 B heat conductive core 154 upon which i6 bonded a fir6t layer 156 of ~llicone els6tomer o de~ired thickne66, ~ second l~yer 158 of ~ 611icone fuæer oil-imperv~ous fluoroela6tomer ~nd ~ th~rd outer l~yer 160 of ~ilicone ela6tomer. Gr~du~
35varying lsyer6 157 and 159 ~ccording to the pre6ent ~nvention ~re respectively intermediflte tv ~nd S~l~

continuou6 with l~yer6 156, 158 ~nd lnyer6 158, 160. Lower r~ller 162 ~6 identlcAl to rolle~ 152 And include6 heat conductive core 164, f~r6t l~yer 166 of 6ilicone els6tomer~ second l~yer 168 of 5 oll-impervlou~ fluoroel~s~omer and ~hird l~yer 170 of ~ilicone ela~omer. Gr~dually v&rying layer6 167 ~nd 169 ~ccording to the pre~ent inventlon ~re re6pectively ~ntermed~ste to and continuou6 with layer6 1669 168 And 168, 170.
Di6po6ed within roller~ 152 snd 162 are he~t 60urce6 6uch 86 quartz tube6 172 ~nd 174 re~pectively. Fuser Gil ~uch ~6 d~methyl m~y be ~pplied ~o the 6urfuce6 of roller6 152 ~nd 162 by ~pplic~tor roller6 17b ~nd 178 re6pectlvely.
A copy ~heet 180 having unfi~cd lmage~ 182 ~nd 184 on oppo6ite ~lde6 thereof i6 p~6ed through the nip formed by roller6 15~ and 162 ~hich Bre held ln pre66ure engagement with e~ch other. The temperature ~nd pre66ure of fixing ehe fu6er ima~e6 20is a function, ~mong other, of the char~cteri~tic of the toner m~ter~ nd the ~mount of time th~t the toner image6 are ln the nlp fonmed by roller6 152, 162.
Example The following ~ ~n example of ~ fu6er roller accsrding to the pre6ent invention whlch 6howed excellent relea~e snd fu6ing qu~lit~e~. The fu6er roller proce66ed ~pproximately 600,000 unimaged copy ~heet6 copie~ w~thout appreci~ble Btep 30form~tion ~n the outer 6urf~ce layer ~nd without del~min~tlon between the l~yers of the roller~ The fu6er roller wa~ produced by mesn6 of ~ppAr~tu~
6imil~r to eh~t 6hown in Fig. 4. The fu6er roller included ~ eore of ~luminum which hsd formed ehereon 3sa $1rst layer of a polydimethyl~ilox~ne ~ilicoDe ela~tomer av~ ble from the Emerson Cummirlg Co.

~æos~

under the for~ul~ No. EC49520 In order to enh~nce thermal conductivity, the 6illcone ela6tomer 1 fllled with thermslly conductive m~teriul6 such a~
alumlnum oxide ~nd lron oxide. Accordlng to the 5 meehod of the pre6ent lnvention, ~illcone el~6tomer W~6 in~tially sprayed onto the fir~t layer to form an intimate l~yer therewith. A6 6111cone els~tomer was con~nued to be ~prayed, ~ fluoroel~6~0mer COmpri6iDg ~ terpolymer of vinylidene flunrlde, hexsfluropropylene ~nd tetrafluoroethylene (VITDN-B50 available from DuPont3 W~E gr~dually ~dded to the 6pr~y mixture until only the fluorel~tomer WL~
6pr~yed ~o ~ de~ired thickne~6 to provide ~ b~rrler layer to ~b60rption of fu6er oil lnto the silicone el~6tomer l~yer. Thenl ~6 the fluoroels6tomer only W~6 continued to be 6pr~yed, 6ilieone elastomer wa6 gradually Ad~ed to the 6pray mixture untll only ~ilicone ela6tomer wa6 6prayed to build up ~ l~yer of 6ilicone els6tomer which would provide good 2orelea6e chsracteri6tic6 for the fu6er roller.
The ~ilicone elfi6tomer ~nd ~luoroel~6tomer were prepsred for 6prsying a6 follow6:
lo To ~ mixture of 150 gr~m6 of the low-boiling point ~olvent methylethylketone and 5Q
2sgr~m~ o the high-boiling point 601vent methyli60butylketone wa6 ~dded 400 gram6 of ~mercon Cumming~ polydimethyl6iloxsne 611icone ~l~stomer identified ~6 Emer60n Cumming6 formula No. EC4952.
Ju6t prior to 6prsying; two gr~ms of ~ cat~ly6t were 30added to the s~licone ela~tomer mixture.
2. A mixture of 30 gram6 of c~rbon blsek, 100 gram~ of methylethylketone solvent, 200 gr~m6 o methyli60butylke~0ne ~olvent, ~nd 10 gr~ms of magne~um oxide ~cid ~ccep~or were mixed together 35well and filtered to remove gro6~ particle6. To the filtered mixture W~6 ndded 100 gr~m6 of methyliso-55i~L

-~o-butylketone 601vent ~nd 100 gr~m~ of ~ fluor~-els6tomer compri~ing a low vi6c06ity terpolymer of vinylidene fluoride, hexafluoropropylene, ~nd tetr~-fluoroethylene av~ilable from ~he DuPoDt Company B6 5 VITON~ B50. Thi6 601uelon wss then ~ixed on ball mill for two hour6. A 6epsrately ~ixed 601ution of 3 gram6 of Cure 20 (8 cure sgene compri6ing 33% orgsnophoæphonium ~nd 67a fluoroel~6tomer), 4 gr~m6 o Cure 30 (~ cure ~gent comprl6ing 50% dihydroxyaromatlc compound ~nd 50 $1uoroel~tomer), 50 gr2m6 of methylethylketone 601ven~ ~nd 100 gram~ of methyli60butylkætone ~olvent were 6ep~r~tely mixed and ~dded 6hortly before ~pr~ying. Thi6 mix~ure ws6 filtered and the filtered m~x thinned by meen6 cf the ~ddit~on of 150 gram~ of ~ethyle~hylke~one solvent ~nd 200 gram6 of methyli~obutylketone solvent. Ihe ~hlnned fluoroels6tomer wa6 then 6ult~ble for ~praying.
Production of ~ multilayer fuser roller ~ccording ~o 2~the pre6ent invention wa6 effected by mean6 of a tWo-hPAd 6pray ~pp8r8tu6 61milar to th~t ~hown ln fi~. 4 ~ follow6:
A roller ~hlch included ~ cylindrlc~l sluminum core h~ving h . 040" ba6e lsyer of 611~cone 2sel~6tomer W~6 mounted and rotated rApldly while the two 6prsy gun~ were reciprocated ~crc~6 the length of the roller. The rotstion~l ~peed Df the roller, the later~l ~peed of the ~pr~y gun~ and ~he rAte of flow of the ela~omer~c ~terl~l being ~pruyed were 306ynchronized 80 that t~e ~nt~re 6urfsce of the roller wn~ covered with ~ co~ting durin~ e~ch 0pr~y cycle (B cycle being efected durlng a back-~nd-forth reciproc~tion of the 6pray he~d~).
A gr~dually v~rying mixture of 6ilicone 35ela6tomer and vlnyl~dene-1uorlde b~6ed fluoroelas-tomer were ~ppl$ed eo the rot~ting roller by ehe two ~ ,2~5 6pr~y he~d6 ln the following p~ttern of elastomer mixture, e~ch 6pr~y heAd belng ~upplied with the lndic~ted proportion of elaseomer.
Table I
-Sil~cone Fluoro-Cycle No. Ela~tomer El~tomer 1 ~/8 0 3 ~/8 2/~

4 ~/8 3t8 818 4t8 6 8/8 5/~
7 ~1~ 6/8 7/8 8/~
11 6/8 ~/~
12 5/8 ~/8 13 4/8 8/~
14 3/~ ~/8 16 1/~ 8/8 17 ~ ~/8 Thereafter, thirty cycle6 of fluoro-25elaseomer only w~ ~pr&yed onto the roller. An outer layer of 6~1icone el~tomer wa~ formed on the fluroelastomer layer by rever6ing the gradu~lly v~rying 6pr8y cycle of T~ble 1 ~8 follow~:

~Z~Sl~
--~2-T~ble ll Sillcone Fluoro-Cycle No. El~tomer Els6tomer 2 l/8 ~/8 3 ~/8 ~/~
4 3t8 8/8 6 5t8 8/~

9 ~/~ 8/8 ll 8/8 6/~
12 8/8 5/~

14 8/8 3/~

16 ~/~ l/8 Thereafter, twenty cycle~ of 6ilicone el~tomer only w~ 6pr~yed onto the roller. The roller W~6 ~llowed to dry overnight. The next d~y 65 cycle~ of 6ilicone ela6tomer only w~ ~pr~yed onto the previou~ 6ilicone ela~tomer l~yer~
The roller W~6 then ~ir cured ~ room temper~ture overnight. The next day the roller wa6 po~t eured a~ follow6: 1 hour ~t 60C; l hour at lODC; l hour ~t 150C; 59 hour6 ~t 205C.
Thi6 roller Wfl~ then mounted on ~ ~u~er soller fixture w~th A roller h~ving ~n aluminum core ~nd an outer l~y~r of .010" of 6ilicone el~6tomer EC4952. Silicone fu6er oil wa6 applied eo the surf~ce of both roller6. The rollerfi were ~n~er~
3sn~11y he~ted to ~ eore ~emperAture of 340F ~nd n~p force of 18 pound6 per l~neal inch of roller ~ 23-length W~6 applied to the roller6. Bl~nk copy ~heets were fed lnto the nlp of the roller6 st a rate of over SOOO 6heet6 per hour.
~fter 600,000 6heet6 were p~6sed through by

5 the fu6er roller, 6eep growth ~n ehe muleil~yer roller WA6 found to be one-h~lf of ehat expected to be found in a fu~er roller hsv~ng a 6ingle ~illcone ela~tomer l~yer of compar~ble thicknes6. Adhe6ion between the fluoroel~6tomer layer ~nd ~ilicone b~6e l~yer w~6 found to be comp~rable both beore ~nd ~fter proce~lng, indicating no deter~or~tion ln ehe ~dhe~ion between the6e layer6 after the 600K ~heet6 were proce 6 fied -The ~nvention h~6 been described ~n dees~lwith psrticul~r reference to the preferret embodiment thereof, but it will be understood thae v~ris~ion6 and modificAtion6 can be effected wlthin thR 6pirit and 6cope of the invention.

Claims

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE PROPERTY OR
PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:

1. The method of forming a member for fusing toner images to a receiver, comparing:
spraying a base member with a first material which is an elastomer;
after a layer of the first material has been formed continuing to spray said first material while spraying a gradually varying proportion of a second material with said first material until only said second material is sprayed; and continuing to spray said second material only to form a layer of said second material.

2. The method of forming a member for fusing toner images to a receiver, comprising:
spraying a base member with a first material which is an elastomer;
after a layer of the first material has been formed continuing to spray said first material while spraying a gradually varying proportion of a second material with said first material until only said second material is sprayed, said second material being impervious to absorption of fuser oil which is absorbed by said first material; and continuing to spray only said second material to form a layer of said second material which acts as a barrier to absorption of fuser oil by said first material.

3. The method of Claim 2 including continuing to spray said second material while simultaneously spraying a gradually varying proportion of a third material which prevents offset of toner thereto; and continuing to spray only said third material to form a layer thereof which contacts toner image to be fused to a receiver.

4. The method of Claim 2 wherein said second material is an elastomer.

5. The method of Claim 2 wherein said first and second materials are high temperature resistant elastomers.

6. The method of Claims 2, 4 or 5 wherein said first material is s silicone material and said second material is a fluoropolymeric-based material.

7. The method of Claim 5 wherein said first material is a silicone elastomer and said second material is fluoroelastomer including fluorosilicone elastomers and vinylidene-fluoride based fluoropolymeric elastomers.

8. The method of Claim 7 wherein said second material is selected from the group con-sisting of the copolymer of vinylidene fluoride and hexafluoropropylene and the terpolymer of vinylidene fluoride, hexafluoropropylene and tetrafluoro-ethylene.

9. The method of Claim 3 wherein said first and third material comprise silicone elastomer and said second material comprises a fluoroelastomer.

10. The method of Claim 9 wherein said fluoroelastomer comprises a vinylidene-fluoride based fluoropolymeric elastomer.

11. The method of Claim 1 or 2 wherein said member comprises a roller and includes rotating said roller while spraying said materials thereon.

12. The method of Claims 1 or 2 wherein said second material is sprayed in a gradually increasing proportion of said second material to said first material until only said second material is sprayed.

13. The method of Claims 4, 5, or 7 including curing said member after completion of said spraying of said elastomer material.

14. The method of Claims 4, 5, or 7 wherein prior to spraying said first and second elastomer materials are respectively dissolved in the same solvent or solvents or in solvents in which both elastomers are soluble.

15. A member for fusing toner images to a receiver comprising:
a composite layer including:
(1) a first layer of a first material which is an elastomer;
(2) a second layer of a second material different from the first material; and (3) a layer intermediate to and continuous with said first and second layers in which the proportion of the first material to the second material gradually varies from substantially only the first material to substantially only the second material.

16. A member for fusing toner images to receiver comprising:
a composite layer including:
(1) a first layer of a first material which is an elastomer;
(2) a second layer of a second material which is resistant to absorption of fuser oil which is absorbed by said first material; and (3) a layer intermediate to and continuous with said first and second layers in which the proportion of the first material to the second material gradually varies from substantially only the first material to substantially only the second material.

17. The member of Claim 16 wherein said second material is an elastomer.

18. The member of Claim 16 wherein said first and second materials are high temperature resistant elastomers.

19. The member of Claims 16, 17 or 18 wherein said first material is a silicone material and said second material is a fluoropolymeric-based material.

20. The member of Claim 18 wherein said first material is a silicone elastomer and said second material is a fluoroelastomer selected from the group consisting of fluorosilicone elastomer and vinylidene-fluoride based fluoropolymeric elastomers.

21. The member of Claim 16 wherein said composite layer includes a third layer of a third material which prevents offset of toner thereto and a layer intermediate to and continuous with said second and third layers in which the proportion of the second material to the third material gradually varies from substantially only the second material to substantially only the third material.

22. The member of Claim 21 wherein said toner offset preventing material is a silicone elastomer.

23. The member of Claim 16 wherein the thickness of said first layer is substantially greater than the thickness of said second layer.

24. The member of Claims 15 and 16 wherein the proportion of the first material to the second material in said intermediate layer gradually increases from substantially none of said second material to substantially all of said second material.

25. The member of Claims 16, 17 or 18 wherein said member has been cured.

26. The member of Claims 17, 18 or 20 wherein prior to spraying said first and second elastomer materials are respectively dissolved in the same solvent or solvents in which both elastomers are solvent.

27. A fuser roller for fusing toner images to a receiver comprising:
a cylindrical core;
a composite layer on said core including:
(1) a first layer of a first material which is an elastomer;
(2) a second layer of a second material which is resistant to absorption of release oil which is absorbed by said first material; and (3) a layer intermediate to and continuous with said first and second layers in which the proportion of the first material to the second material gradually varies from substantially only the first material to substantially only the second material.

28. The roller of Claim 27 including a second roller forming a nip with said first roller through which is passed a receiver carrying at least one toner image to be fused by said rollers.

29. The roller of Claim 27 wherein said core comprises a cylindrical shell of heat conduc-tive or heat transmissive material and inluding a source of heat located within said shell.

30. The roller of Claim 27 wherein said second material is an elastomer.

31. The roller of Claim 27 wherein said first and second materials are high temperature resistant elastomers.

32. The roller of Claims 27, 30 or 31 wherein said first material is a silicone elastomer and said second material is a fluoropolymeric-based elastomer.

33. The roller of Claim 31 wherein said first material is a silicone elastomer and said second material is a fluoroelastomer selected from the group consisting of fluorosilicone elastomer and vinylidene-fluoride based fluoropolymeric elastomers.

34. The roller of Claim 27 wherein said composite layer includes a third layer of a third material which is an elastomer which prevents offset of toner thereto and a layer intermediate to and continuous with said second and third layers in which the proportion of the second material to the third material gradually varies from substantially only the second material to substantially only the third material.

35. The roller of Claim 34 wherein said first and third material are silicone elastomers and said second material is a vinylidene-fluoride based fluoropolymeric elastomer.

36. The fuser roller of Claim 27 wherein the proportion of the first materal in said intermediate layer gradually increases from substantially none of said second material to substantially all of said second material.

37. The fuser roller of Claims 27, 30 or 31 wherein said fuser roller has been cured.

38. The fuser roller of Claims 30, 31 or 35 wherein prior to spraying said first and second elastomer materials are respectively dissolved in the same solvent or solvents or in solvents in which both elastomers are soluble.

39. The method of fusing a heat-softenable toner image to a receiver which comprises pressure contacting a heat-softenable toner image carried by a receiver with a fusing member at temperature effective to fuse said toner image to said receiver member, said fuser member having a composite layer including:
(1) a first layer of a first material which is a high-temperature resistant elastomer;
(2) a second layer of a second material which is a high-temperature resistant elastomer; and (3) a layer intermediate to and continuous with said first and second layers in which the proportion of the first material to the second material gradually varies from substantially only said first material to substantially only said second material.

40. The method of Claim 39 including applying fuser oil to said fuser member.