Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
~OG73Z6
~ackground of the_Invention
With the increased use of plain paper copiers, development
powders have en]oyed an increased popularity over liquid toners.
~long with the increased use of development powders, magnetic
brush units are becoming increasingly popular as opposed to cas-
cading methods. Development powders used with magnetic brush units
usually have an iron powder which serves as the carrier material.
,; , . .
Inexpensive, untreated iron powders cannot be used in magnetic
brush systems since such iron does not have sufficient stability
toward rusting and has color and triboelectric charging properties
adv~rsely effected by variable humidity conditions. In order to
solve this problem, those in the art have resorted to chemical
plating and coating of the iron particles with polymers, oils,
waxes and the like.
Prior art developer materials, which are employed in
automatic copy machines, have carrier filming problems due to the
.:
mechanical rubbing of the carrier surface with the soft toner resins.
The gradual accumulation of permanently attached film impairs the
normal triboelectric charging of the toner particles in the toner
mix. As a result, the toner is either less hlghly charged or ~ , ;
sometimes oppositely charged giving rise to poor copy quality
with a high degree of background.
In the literature, several types o~ plastic coating and
electroplating o~ the carrier have been suggested to overcome ;
the filming problems. Most of the prior art coating methods
result in high cost and have other disadvantages such as yielding
improper triboelectric charge properties and imparting a very high
::.
electrical resistance to the carrier that reduces its development
electrode e~ect and results in poorly filled-in large image areas.
:,,:,. .
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;''.' ':J ' ' ~;
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7326
Summary of the Invention
In the art of electrostatographic imaging proceq~, an
el~ctrostatic latent image is formed on a recording surface of a
photoconductor. The electrostatic image may then be deveioped
by finely divided toner particles electrostatically attached to the
surface of carrier particles. Preferably, the carrier particles
are iron powder or beads.
It has be~n found that a simple perfluoro adsorption -
. :
treatment of iron powder from a solvent produces a treated
iron which has good stability to rusting under high relative
humidity, a constan~ triboelectric charge property under all
conditions when mixed with standard toners and very low dusting
of the toner in a magnetic brush unit and allows the use of
lower reverse biased voltage during development which improves
the reliability of machine performance.
By using the treated carrier particle~ of this invention,
an improved electrophotographic process is obtained. In this
improved process, a latent electrostatic image is contacted with
J`' .`
a developer mixture including the treated carrier particles
of this inventio~.
s; Brief Description of the Drawing
The single figure is of a graph showinq the effect of
perfluoro component solvent concentration on the charge to weight
, ~; ratio of treated iron powder.
Description of the Preferred Embodiment
,~ ~he core of the carrier particle formed by the present
' ~ ~ invention may be any material which can react chemica}ly with the ~-
perfluoro compounds of this invention. Thus, by way of example,
. " ,.~ .
~- the material of the core of the carrier particle may be sand, gla8s
~,$ beads, metallic beads or metallic powdersO As used in this
~ specification, including the appended claims, the term metal ;
G ~ :
,~ 3
.".-." ' ,'
~' .
~r~ ~
., . . .. . . . . .
.. ,...... . . . . . . . .. . ~.
~ ..... . . ., . . ~ . ... . . .
, .. ,.. , , . , . . ~ . , .. ~ .
, . ~ . .. ..
~ ~; . . . . . - .
~0673;26
~ and metallic is in~ended ~o incl-ldc cleme1ltal metals a5 well .lg
.,3 ' their oxides, carbide~ and other forms of mctallic compounds
~; and alloys which have a solid form.
.. .
The core o carri~r particles o the preferred ~mbo~iment -
.:. . ~ .
is a ferromagnetic material such as iron or steel. Other suitable
~, ferromagnetic materials such as ma~netic oxid~s and alloys of
copper-nickel-iron, for example, also may be employed. The
`~ size of the core may be between 40 and l000 microns with the
preferred size range being between 50 and 400 microns.
;, 10 The perfluoro compound is selected from a number.of classes
including perfluoro alkanes, perfluoro alkyl ethers, perfluoro
; alcohols, perfluoro amines, perfluoro amldes, perfluoro es~ers,
:!~ ': : - '
perfluoro acids, and the like.
Perfluoro alkanes of the formula F.(CF2)n.F, where ~ is
equal to or greater than 6, can be used. ;Compounds of the type
lH perfluoro alkane H.CF2.(CF2)n.CF3 can also be used. Speclfic
~; examples of the first class are~perfluoro hexane, perfluoro~
heptane, pèrfluoro alkane-70,~perfluoro alkane-80, perflaoro .
~ alkane-llS, perfluoro alkane-l95,~perfluoro kerosene-L, perfluoro
~" 20 ~ kerosene-H, e~c. Examples of the~ perfluoro alkane are 1
perfluoro heptane, lH perfluoro octane, etc.
oi ~ Examples of perfluoro alkyl po~y~ethers aré-flQrinated
oils such as KRYTOX~143* available from~DuPont de Nemours & Co.
~'t"'~ and FOMBLIN-L*, FOMBLIN-M*, ~OMBLIW-H* and FO1~LIN-U*, all
avail~ble from PCR Inc., Gainsville, Florida.
Fluoro alcohols suitable for the treatment~are perfluoro ~ ~`
alcohols of the formula: ~
- ~ ( 2 CF2)n C'~2~1 or ~1.(CF2-cF2?n.cl~2Oll where ~ 7
such as lH, l~1-perfluorooctanol; l11, l11, 911-perfluorononanol;
lH, ll1, l1H-perfluoroundecanol; l11, 111,~311-porfluoroyropanol;
*TradPmark
.~ ., " ~
73Z6
and 111, 111 511-perfluoropentclnol. ~lso suitabl~ are ~econdary
and branchcd chain alcohols such as H. ~CF2) 4.C110H.C~13,
.(CF2)4.COII(C113)2 and 1~(CF2)8C~I~CH3) C112OII- Other
.::
~'" . fluorinated alcohols useful in this invention are o~ the - /.~
formula F. (CF2)n.(C112)m.C1~2OI~ where n is an integer from l-9 .. :
and m is an inteyer from 2 10. ' - .~:
Fluoro amines sui-table for the treatment are primary,~ :
secondary and tertiary perfluoro'amines, for example perfluoro
tributyl amine.
. , ~ , - . . . :
' Also usable are fluoro amides of tlle composition
F.(CF2)n.CONH2 where n = 4 to 10, for example perfluoro ' ~
' sctanamide. Branched as ~ell as.-C1~2-~sequented amides can
.. ' ~ be used.'
~' : Partially fluorinated aliphatic diesters with surface~
.:,; . ~ . ~ .
active compositions may be employed and have the.~f~rmulae~
P (cF2)mOoc CH (CH2)xcOO(cF2)m
. and ' :~
~20 ~ H (cF2)nooc CH(CH2)xcOO(cp2)n ~
where R ls hydrogen, C2 to C12~straight~chain alkyl, C2 to C12
1?'~ straight chain alkenyl or phenyl, m is~:an~inte~er from 5~'.to~
;. ~ x~is an integer from 1 to 7 ,~ and n is an integer~from 4~-to 10.
The acid portion of such dlesters may~be, for example, a:
:. succinyl, glu taryl, adipyl, pimelyl, sùberyl, azelayl or:~
. : sebacyl radical; a methyl-,'n-propyl, n-butyl-, n-dodecyl-, -
' n-octenyl-, or n-dodecenylsucclnyl~ rndical; a phenylsuccinyl
: radical, a 3-methyl-, 3-butyl-,:.3-dodecyl- or 3-~octenylglutaryl
radical, a 3-phenylglutaryl radical;:a 4-mçthyl-, 4-octyl or
:::............. , , . ~ i " .
?'~
~ ~0~73~;
4-phenyladipyl radical; a 7-mcthyl-- or 7-ethylazelnyl radical;
or a 7-phenylazelayl radical. Typical esters within the above
formula are bis-(perfluorooctyl) n-dodecenyl succinate, bis-
~perfluorohexyl) 3-methylglutarate, bis-(perfluorooctyl) 3-
methylglutarate, bis-(7-hydroperfluoroheptyl) 3~methylglutarate
and bis-(7-hydrop~rfluoroheptyl~ 3-phenylglutarate.
Fluoro acid compounds suitable for the treatment are
.. . . . .
perfluoroalkyl monocarboxylic acids of the formula:
i F(~F2)nC
0 where n is an integer from 1 to 13, for example: trifluoro
~ acetic acid, heptafluoro butyric acid, ~erfluoro decanoic -~
. - . , . .: , ~
-~ acid, perfluoro-n-octanoic acid, etc., branch chain perfluoro ;
alk~l monocarboY.ylic acids of the formulae~
~ ~ (CF3)2.CF(CF2)n.COOH and (CF3).(CF2Cl).CF.(~F2)n.COOH
t'.'.. ' where n is an integer from 1 to llj and includes 3-tr-ifluoro-
methyl perfluoro butanoic acid,~ 3-dlfluorochloro methyl per-
fluorobutanoic acidl 13-trifluoromethyl perfluorotetradecanoic acid,
etc partially fluorinated monocarboxylic;acids of the formula:
t ~ (CF2)n-(CH2)~;m-~cOoH
~;D~ ~ ~ where n is an integer from 1 to 10 and m is~ an~integer from 2~to
16,~and includes 4-trlfluoro methyl-butanolc acid, ll~(heneico~
fluorodecyl)-undecanolc acid, l7-(penta deca1uoro~heptyl) hepta - ;
~ decanoic acid, etc., and partially fluorinated monocarboxylic
t; ~ acids o the~formulaO .
I(CF ) COO~
where n is an integer from 1 to~l4, for example 2~1-difluoro-acetic
acid, 7H-dodecafluoro heptanoic aoid, 1111 eicosafluoro undecanoic
: acid, etc.
6 -- -
cm/p~
r ~ ;:
. -.
~:
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.. . .
;73;~6
The abovc classiflc~tion of the perfllloro compound~
that can be used ln the prcscnt invention ls not llmiting. Othcr
p~r~luoro compounds such as ke~ones, aldehydes, nltriles,
- sulphon$cs, etc. can also be used.
The perfluoro alkanes, ethers, seem to give only
temporary protection to the carrier surface. The perfluoro
.
amines, amides and esters seem to give fairly lon~ life to the
carrier. The longest life is obtained with the acids and
- alcohols.
As a typical carrier, ANCOR STEEL~ (Hoegen~es) ?oO0s
~. .
(-80/+230 mesh) Hoegenaes9 Inc~, New ~ersey was used. Spherical ~-
; lron powder from ~uclear Metals~Division ~hittaker Concord,
Massachusetts was a l s o u s e d .
Commerical toners may be~used iD~conJ~1nction ~ith
perfluoro treated iro~a powder. ~Examples o f such commerical toner
are ISC l00g-l4A toner made by~Imaglng Systems Corp., Toner
67-146 made by Phillip A. Hunt~Chem1cal~Corp~, and~IBM Toner
H 1162058. A non-comr1e~rclal toner~used in combination with tbe ~;
perfluoro treated iron was a composition of 45.~ parts styrene- -
~20~ butylmethacrylate copolymer, 45.5 parts Pliolite VTLb (Goodyear
Chemclals), 6 parts ~logul-L* (Cabot Corp.3~and 3 parts nigrosine
bas~e NB (GAP Corp.).~ This non-commerical toner is herei11after
- referred to as PB toner. The p~r~epared toner coTIcentrate in~the
, ; ; devel~per mix is between l and~3X, the bnlanco being p~rfluo;ro
treated powder.
The perfluoro treatmene of the carrier particle is~ ;
~ccomplshcd by tumbling tl1e core materinl for about 30 to 45
~minutes in nn approprlate solutlon~cnntaining ~y of tho
; per1uoro compounds enumern~ed previously.~ After tumblin~, t11e ~;
Tradcmark ~ ~ 7 ~
d a p~
: - . : F :
, :', ~ ' - ' ' ': ' -
i. - . ~ '
r ~70673Z6
solution is decanted and filtered and the core m~terial is
heated in an oven, for example at 50-75C, untii dry. The
treated core material may then be used as a carrier particle
,
. in.a developm~nt powder.
-Suitable volatile solvents for the l.iquid con.~ositions
of the invention are halocarbon solvents such as liquid perfluoro-
alkanes and fully fluorinated bromo and chloroalkanes, for example,
perfluoropentane, perfluorohexane, trlchlorofluoromethane, dibromo~ ~ ~
: difluoromethane, tribromofluorome~hane, l,l,2-~richloro-l,2,2-tri- : .
fluoroethane, l,2-dibromo-l,l,2,2-tetrafluoroe-thane,l,L,l-trichloro-
- 2,2,3,3,3-pentafluoropropane, l,l,1,3-tetrachloro-2,2,3,3-tetra-.
- fluoropropane and 2,2,3-trichloro-ljl,l,3,4,4,4-heptafluorobutane, :~
mixtures thereof, and l,l,2,2-tetrachloro-l r 2-difluoroethane, M.P. ~
26 C., in liquid form or in solution in one of the liquid perfluoro-
~-:alkanes or liquid fully florinated bromo or chloroalkanes. : ..
~ Other solvents which may be used include MEK, acetone, ::::
mineral spirits, naptha and the like. It has been found that :
~ . these latter solvents may be mixed with the halocarbon solvents.
listed above for better coating results at.lower cost.
~20A typical concentration range for the perfluoro compound
,
- to solvent is o. ui - 10%t the preferable range being 0.1-0.2%. ;~
The following perfluoro compounds have been used ~ :
successfully to treat iron powders which are used as carrier~
,.. ~ particles: Perfluorokerosene-L;~ 1,lH, 911-perfluorononanol3;
..(lH, l~-perfluorooctanol); perfluoro decanoic acid; (llH-per~
~:fluoroundecanoic acid)1 perf1uoro-n-octanoic acid ~erfluoro~
octanamide; perfluoro tributylamine; (lH, lH, ll~1-perfluoro~
- undecanol); and perfluoro esters.~- bis ~2,4' pentoxy~
. : -
~ cm/~7h - 8-- -
.c~
. : . . .
,, ,- ~ - ,, ~
., ,
, . ., : , .
.'' . . ;
. - ' , ., .
. . .
~L~6~73Z6
;~etra1uoro propyl)-3-me~lly]~ r,~c all o~ which arr available
from rCR, Inc., Gnlnesville, Florid~. In addition, perfluoro
.. . .
allcyl ethers, avalla~le from E.I. ~uPont de'Nemours Chemical
Corporation, Wlll~ington, Delaware, und'er thc trademark KRYTOX.
Preferably the perfluoro treatcd iron is mixed with
a toner at a ratio of 98:2 respectlvely. These ratios are hased~ ~'
on weight as are all ratio and percentage fi~llres in this '~
specification. The developer powdcr is evaluated using the-
~' following tests~
' 10 A. Faraday Cup measurement: these are carried out `
'- as a function of perfluor~o treatment and expDsure to
~- various humidity conditions. It yields a charge ~o
mass measurement that indicates the effecti~erLess
of the treatment.
I . . .
:~ B. Step tablet measurements: this~gives an indication
- as to toning'characteristics oi~ the developer powder.
lectrica].ly insolated spots o 1 CD ~1n diamete~r nre~
` ' back charged in potentials of increasing ~oltage end
~; ~ ' increments of 10 V. These spots are developed to
~- 20 ~ completion with the developmel~t powders flom a manual
magnetic brush. The spots are evaluated for print
.. : . .: : :
' ~ ~ - de~sity fill ln and other'visually observab-le ~ '
Ç ' charocteristics,~
C. Machine evaluation of the developer powder in a - '~
'`~ plain paper copier such as the PBC~4500 Copier*,
'~ Copier Division, Pi~ney-Bowes, Inc., Danbury, Conn.
: : , . . ~ : .
~-~ Table 1 lists the Faraday~Cup measurements. It is ~ ;
seen that the treatmen~ affects the triboelectric property of the~
lron sur~ace a;ld as a result, one may obtaill any deslred CIM
.; ~ , .
* Trndemark
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'' : ' - . :
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~i73Z6
ratio by choo9in~ the propcr pcrfluoro compound. The third
colu~n glve9 the C/M aftcr the dcveloper~ havc be¢n ex~oce~ ~D
75Z/R'l at 68 F. for 3-4 day6. The ~st column gives the per- .
centage drop ln C/~ whQn the deveioper powder is exposed to hi~h
: . ' ' . :: '
: R.H. .
Ideally one would like to have no drol? in CJM at hi~l
;~ R.H.
TABLE I
Charge Charge
coul/g ~-coulJg ~ Percent ::
~ Room 75/RH 68 F ~ Char~e
: Compound . Condition for 3-4 days: of Char~e :::
Untreated Iron . 4.8 .~: 3.4 ~ 29.7
~ Washed~with Solvent ~ 4.0;~. ~ 3.3 16.0
; ~- Perfluorokerosene.L ;~ 4~.6~ 2.4~ ~~ 32.6 ^~
- : Perf].uoro Alkyl Ethers ~ ~6.. 4~ S.O -~ 22.4 :~
Krytox from DuPont)
, lH, 9ll-Perfluorononanol ~ 5.6~ 4.0 ~ ~ 28
20 ~. lH, lH-Perfluorooctanol: 7.8 ~ 6.3 : 19.6
Perfluoro Decanolc Acid ;~ ll.9 :~ 9.3 ~ ~ 21.8
: : llH-Perfluoroundecanoic .: :9.1 :~ 9.2 ~ ~1.4 :
Perfluoro-N-Octanoic Acid ; ~ Cha~rge Reversa}
Per~luoro.Octanamide ~ ~10.9~ .;9.5 ~ . 12.8;::~
:: Perfluoro Tributylamine 5.0~ 4.0 ~ 19.4:~
lH, lH, ll~-Pereluoroundecanol 7~.~8 ~ 6.5 19.5
:.:: . . , : . , ~: ~
~ The perfluoro concentrate in~tlle soluLion was 0.2% in
all cases except in ~5 where it was .O5
The ~raph~of the dra~lnE~shows the ~ypical eE~fect o f ~
: . . :conccntrate of perfluoro compoun~ on C/M. The curve ~a~ obtained
8p ~
"'' '' ' ' .. ' ,',.:' ' , ,, ''
'' ' - , - . '`''
, , , . ~ .
'.' ~ : ' ' '' , , ', : ` : , ~:-
~1~)673Z~
for iron pol~cr tr~c~l wltll 1111 ycr~luorollndecanoic acld.
It i8 secn th~t the C/M incrcns~s r~pldly, rcacllc~ a
pla~enu until hl~her concentrations are reac!led, tbcn the C/N
.dec~eases. . . .
: - Example.I
s A quantity of 0~05 gms. of ll~ perfluoroundccanoic
acid W~5 dissolved in a mixture of 20cc trichloro hept~luoro
butane (HALOCARBON # 437, Haloc~rbon Co., New ~ersey~ and 10cc
. ~ . '
- -
;. . - .- - . , : -
.
10a
~: dup/p~
~.. ,.:, :~ .. , . . . :
~': '' . :' .
- ~673Z6 ~
of me~h~l ethyl ketone. To this solvent wai~ added 30 gm. of
iron powdes (Anchor Steel lOOOS) having a mesh of -80~230. The
ci~ntents were mixed for 1/2 hour and then the supernatent wais
~ecanted. The remaining treated iron powder was dried in an
oven at 100 C. for two hours. This treated iron powder was mixed
with tha ISC toner lOOg-14A in a ratio of 98:2 respectively. The
davelop-ent powder wa~ used intermediately over a 6 month period and
t.:
was ~o~-d to retain its excellent propertie Good results were
achieved when used to produce plain paper copi~s in a P~C copierO
Example II
. . - .
guan~ity of 0.05 gms. of tper~luoro kerosene-L) was~
~,~ dissolvad in a mixture of 20cc trichloro heptafluoro butan~ and
lOcc of ~ethyl eth~l ketone. ~o thii3 solvent was added 30 gm.~ of~
iron po~de~ (A~chor Steel lOOOs) having a~mesh of 80+230. The
contents were .~ixed for 1/2 hour and then~the supernatent was
` dicanted. The re~ininS treated iron powder was dried in ~
oven at 100 C. for two hours. ~This treated~iron powder was mixed
wlth the ISC toner lOOg-14A in a ratio o~ 98:2 respectively. ~ s
si~ ~ A quantity of 0.05 gms. o~ (Xrytox) acid was~dissolved in
a ~ixturs of 20cc~trichloro heptafluoro butane and lOcc o~ methyl
ethyl ke~one. To th$s solvent was added 30~gm. oS lron powder
nchor Steel lOOOS) having a mesh o~ -80~230. The content3 ~
~; were mixed ~or 1/2 hour and then the i~upernatent was decanted.
The ~e~aining treate~ iron powder was dried in an oven at 100 C.
or two hours. This treated iron powder was mixed wlth the ISC
$ - toner lO~g-14A in a ratio o~ 98:2 respectively. The developm~nt~
.~J" po~der waY used intermediately over a 6 Nonth period~and was ~ound
to ret~in its excellent p~opertie~. Good~results were achieved
when used in a PBC copier.
- r_~ ~
.~' ' - ~
-
673Z6 - ~
ExampJc IV
A quantlty of 0.05 ~ms. of lH, 1ll,, ~ pcrfluorononanol
wa~ dissolved in 30cc o~ a solvent made up of 67 parts Freon-ll*
(DuPon~) and 33 part~ methyl cthyl ketone. To this solution was
added 30 gm. of iron powder (Anchor Steel lOOOS~ having a mesh
of -80+230. The contents were mixed for 1/2 hour and then the
supernatent was decnnt~d. The remaining treatod iron powder was
dried in an oven at lOO~C. for two hours. This t'reated iron
po~der was mixed with the ISC toner lOOg-14A in a ratio of 98:2,
respectively. The development powder ~as used intermedia~ely'
:, . . : . ,
'- o,ver a 6 month period and was found to retain its excellent
propert$es. Excellent plain paper copies were produ~ced in a
. .
,' ~- PBC copier uslng this development powder. -
' ~ Example V
~ A quantity of 0.05 gms. of perfluDro decano$c acid uas
,''~ diss'olved in 30cc of a mixture made up of~67 parts Freon-ll
~'' (DuPont) and 33 parts methyl ethyl ketone.'~ To this~solven~
was added 30 gm. of iron powder~(~Dchor Steel~lOOOS) having a,
.mesh of -80+230. The contents were~mixed ~or 1/2 hour and~Lhen
~,20 the supernatent was decanted. The~remain~ing~ tre=ted iron poader
was dried in an oven at 100C.'for two hours. This treatcd iron ~-'
powder was mixed with the ISC toner~lOOg-lbA~in a ratio of 98:2 ,~
respectiveiy. This development powder was used in a PBC copier
,-' intermediately over a six month per~iod and gave good results.
Example VI
~ A quantity of~O'.05 gms. of perfluoro n-oceanoic acid ~" ;'
." ~ was dissolved in 30cc of a mixture of 67 pnrts Freon-ll* (Duront~
k : and 33 parts methyl ethyl kctone. To this solvent was added
,,~ 30 gm. of iron powder (~nchor S~e'ol lOOO.S) having'a mcsh ' '~
~, * Trndemark - 12 -
' dRp/~
F
',, , ' - ; ,: '
', ' .
, ~ - ,, :. . .. ,.: ... .
~ 73~26
~f 80t230. Thc ~on~cncs wcrc ml~cd for 1/2 hour .Ind tllcn ~he
supern~tent w~ decan~ed. Tha rem~inln~ t:re~ted lron powder was
dried in ~n ovcn, This treated lron powder was mlxed wlth the
ISC toner 100~-14A in a r~tio of 98:2 respectlvely ~nd tlle
development powder was te~ted. ~ood propcrtles resul~ed.
Ex~mple VII
A quantity o 0.05 ~ms. of perfluoro octanamlde acid -
was dlssolved in a mix~ure made up of 67 parts Freon-ll (DuPont) ~
and 33 parts methyl ethyl ketone. To this solvent ~las added
: ,
30 gm. of iron powder (Anchor Steel lOOOS) having mesll of
-80+230. The contents were mixed for 1/2 llour and then the
supernatent was decanted. The remaining treated iron powder was
dried in an oven at~100C. for two hours. ~This treated iron
powder was mixed with the ISC toner lOOg-14A in a ratio of 98:2
respectively. The development powder was~ used in a~PBC copier
intermediately o~er a six month period and wa~ found to yield
good results.
Bxample VIII
A quantity of 0.05 gr,ls.~ of (perfluoro tributylamine)~
was dissolved~in a Freon TA (Du~o~t). To~thls solv;en~t was added
30 gm. of iron powder (Anchor Stee~l lOOOS) having a mesh of :
80+230. The contzllts were mixed for 1i2~hour, the supernatent
was decanted, and the remaining trèated`i~ro~n powder wae dried. ~-
This ~reated iron powder was mixed~ Witll the ISC toner lOOg-14~ -
in a ratio of 98:2 respectively,~ Good properties wDre obtalned
vhDn the development powder wDs t~sted.
x~mple_IX
A quantlty of 0.05 gms. of 111, 1}1, llll-perfluoroundecaDol
wa8 dissolved in 30cc Preon TA (DuPon~). To this solvent aDs ;~
* Trademark ~ - 13
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s~B - ~ ;
.. . . . ~ . -
. ~ ~ ~
~ . ~ .. . . .
;
., .
....
/ ......... . ; ~ , ~
..
' ~673~6
n~d~d 100 E~ of lron powdf~r (Ancl~or S~ccl lOOOS) havLn~ .i me~h
of 80+230. The contellt~ were mixed for l/2 hour a,nd then ~lle
supernatent was decanted. The remalnin~ treated iron powder wns
drlbd ln an ovcn a~ 100C~ for two hours. This treated iron
powder was m'ixed wlth the ISC toner 100~-]4A in a ratio of 98:2
ref~pectively. The development powd~r was tested in a PBC copier
intermediately over a six month period and was found to yield
good results as well as retain its excellent properties.
.. . .
' I xample
-A quantity of 0.05 gms. of llll-perEluoroundecanoic
'acid was dissolved in Q mixture of 20cc trichloro lleptafluoro
butane (HALOCARBON #437, ~alocarbon Co., New~Jersey) and lOcc
of methyl ethyl ketone. To this solvant was added 50 g~. of~
~hitaker iron powder having a mesh'of -80~230. The iron is mixed
.. - - , ~ : ,: . .
' ~ with ISC lOOg-14A toner at a concentratlon oE 2X~and evaluated~
',~ in a PBC copier. The contents,were' mixed for i~2 hour and then
'' ~' -~ the supernatent was decanted. The remaining treated iron powder ,
was dried in an oven at 100C. for'two hours. Tliis treated iron
powder was mixed ~ith'the ISC lOOg-14A~toner~at a concentration~
.: ~ . : , . - ,~
of 2%. The development powder was~evaluated in a PBC copier '
and~used intermediately over a six month period. Excellent
resules wero achieved.
~XAMPLE XI
'' ~ A quantity of 0.05 gms. of llH-perfluoroùndecanoic
', ' scid ~as dissolv~d in a mixture of 20cc trichloro heptafluoro ,. . . .
' butane (HALOC~RBON #437,-!l locarbofn Co., New ~ferseyj and lOcc
- _ . , ~ . . . -
$ -~ ; ~f mechyl et!~yl ketone. To~thi6 solvent~was added lOO gm. of '~
~' ~ron powder ~Anchor Stcel lOOOS) havin~ a mesh of -80~230. The~
'" ~ contents were mixèd for~l/2 hour and tben th~e supernaeent ~fas ,~
f" - -
14
d~pir~
,
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,. .. . ~
~.. ' ~ : ~ . ' .. ' :
. -; : . . .
.. . . . . .
- , ~
3;~6
dec~nted. The r~m~inlng tre~ted iron powdcr was dri~d ln ln OVCII
a~ 100C. for two hcurs. Thl~ ~reated lron powder was blol~dc~ -
with PB toner ln a ratio of 97.6:2.4 respectively. The resultlne
devclopment powdcr was t~sted in a PBC copicr intermediatPly
. . .
over a slx moDtll period and ex&ellc~t res~llts were acllieved.
Example XII
A quantity of 0.05 gms. of llH-perfluoroundecanoic
acid was dissolved in a mixture of 20cc trichloro heptafluoro
butane (~IALOCARBON #437, Halocarbon Co., New Jersey) and lOcc
.. . . .
of methyl ethyl ketone. To this solvent was added 30 gm. o~
iron powder (Anchor Steel lOOOS) having a mesh of -80+230. Tlie
- . ..
contents were mixed for 1/2 hour and then the supernatent
was decanted. The remaining treated iron powder was dri-ed in an
oven at 100C. for two hours. This treated iron powder was mixecl ~--
with the Hunt toner #67-146 in;~a ratio of ~7.6:2.4 respectively.
- The pllysical properties of the development~powder was tested and
f~und to be hi~hly satisfactory.
~ - Example~XIlI
,` - ~ A quantity of 0.05 gms. of llH-perfluoroundecanoic
-~ 20 acid was dissolved in a mixture of 20cc~tT~ichloro heptafluoro ~~
- but~ne (HALOCARBO~ #437, HalDcarbon, Co.~ New~Jersey) and lOcc
- of methyl ethyl ketone. To this solvent~was added 100 ~m. o~f ~;
~ . iron powder (Anchor Steel lOOOS) having-a mesh of -80~230. The ;~
i~ ~ content were mixed for l/2 hour and then the supernatent was
decantedO The remailling treated~iron powder was~dr;ied in an oven
at 100C. for ~wo hours. thi8 ~reated iron powder was mix~d
with the I~M Copier II toner in a ratio of~98:2 r~spectiv~ly.
~''.` : ' ' ' ' ' ' .: ~-
~ d~p/~hJ
, - . . '
' ~ . ,': ' .
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: ' , - ' .
., , , ~ .
, . : ~:
'',':'` ' ' '' ' '. '.""'.. ',' ' ~' ,
73;~6
;~ . '
,
Copies produced in those tests above wherein the development
powder was used in a copier showed good fill-in, good resolution and
low background. The copier in each instance was operated at -100
volts bias instead of the standard level of 135 volts. The lower
bias is possible because of the characteristics resulting from the
perfluoro treatment. Additionally, iron pull-out was reduced to
10~ of what was previously experienced without perfluoro carrier
particles.
It will be appreciated that the ratios of iron powder to
toner disclosed in the above examples are for development powders
newly charged to a copier and tlqt the development powder had to
be replenished with toner and carrier particles in proper proportion -
:: .-: , .
as the same were consumed.
~:~ What is claimed is:
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