CA1306137C - Silver-based electrostatic printing master - Google Patents
Silver-based electrostatic printing masterInfo
- Publication number
- CA1306137C CA1306137C CA000535809A CA535809A CA1306137C CA 1306137 C CA1306137 C CA 1306137C CA 000535809 A CA000535809 A CA 000535809A CA 535809 A CA535809 A CA 535809A CA 1306137 C CA1306137 C CA 1306137C
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- approximately
- monomer
- carboxylic acid
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- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
- G03G5/00—Recording members for original recording by exposure, e.g. to light, to heat, to electrons; Manufacture thereof; Selection of materials therefor
- G03G5/02—Charge-receiving layers
- G03G5/026—Layers in which during the irradiation a chemical reaction occurs whereby electrically conductive patterns are formed in the layers, e.g. for chemixerography
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- Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- General Chemical & Material Sciences (AREA)
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Photosensitive Polymer And Photoresist Processing (AREA)
- Photoreceptors In Electrophotography (AREA)
- Printing Methods (AREA)
- Materials For Photolithography (AREA)
Abstract
TITLE
IMPROVED SILVER-BASED ELECTROSTATIC PRINTING MASTER
ABSTRACT
Compositions and films are provided for the preparation of electrostatic printing masters. The composition binder permits use of aqueous silver halide photographic techniques to image the master for printing, and exhibits insulation properties needed for electrostatic printing under typical conditions of relative humidity.
IMPROVED SILVER-BASED ELECTROSTATIC PRINTING MASTER
ABSTRACT
Compositions and films are provided for the preparation of electrostatic printing masters. The composition binder permits use of aqueous silver halide photographic techniques to image the master for printing, and exhibits insulation properties needed for electrostatic printing under typical conditions of relative humidity.
Description
3~7 TITL~ P~-2309 IMPROVED SILVER-BASED ELECT~OSTATlC ~ ~N~5lNC~y~
BACKGROUND OF_TH~ _NVE~ TION
Thl6 inventio~ relatefi to elec~rostatic ~rinti~g and, more par~icularly, ~o a~ i~proved electrostatic printin~ ~a~ter adapted ~or the u~e o co~ven~ional ~ilYer halide ~hotogra~hic technigue~
during ~rep~ration of the ~a6teY ~or pri~ti~g.
; Ele~tro~tatic p~inti~g i6 ~ell-know~ ~n the art and ha6 been propo~ed ae a~ alternatiYe ~o ot~er : ~ri~ting te~hnique6. In one method o~ electEosta~ic ; prin~ing, one f ir~ ~repare~ a "~a~er~ tha~ i~
capable o~ ~electively holding electro~ta~ic ~harge$
to for~ the desi~ed i~age. The master i~ expo~ed to a corona di6charye that forms a latent elec~rostatic image, and contacted with dry or liquid toner of the oppo6ite electrostatic charge to develoe the i~age.
The toned image i~ then tran~ferred ~o a sub~rate, typically paperO where the toner i6 fu6ed ev fix ~he image, a~d the ~a~ter i~ retur~ed for the ~e~t printing cycleO
It has been 6ugge6ted in U.S. Patent 4.069,759 that an i~roved electro6ta~ic p~i~ting ~a~ter ca~ be fabricated by disper~ing a ~onve~tio~al 6ilve~ halide photographic ~alt in an in6ulating polymer (e.g., gelati~)~ and coa~ing the di~persion on a conducting substrate. The coating i8 expo6ed : i~agewi6e, and i~ developed to ~au~e ~he exposed 6ilve~ halide to be reduced to metalli~ ~ilver~ The 30 u~expo6ed ~ilveE halide ~ then di~601Yed and ~emoved from the coating to fix the i~age. ~hile the ~aster 6ugge6eed in U.S. Patent 4,069,7Sg offers many advan-tage6, and per~it6 the u~e of ~onven~ib~al aqueous ~ er halide photographic che~istry whe~ gelatin iB
35 ~ele~ted a6 the in6ulating polym2r, it has bee~ Pound .
~ t7 tha~ gelatin is tGo highly 6en~itive to humidi~y to hav~ prac~ical application in a typical workplace.
~elatin rapidly ab60rbs ~oi6ture ro~ the ai~ and at ~odera~e to high humiditi~6 no lo~gel fun~tio~s a~ a~
in~ulaSing medium, bu~ provide~ a ~onclucti~e path ~hat g~ound~ ~ur ace ~hargei impoced on the master during the electro~ta~ic prin~ing ~roce~.
Thu6. ~here i~ a need for ~n improved electro~tatic printing ma6ter that will offer ~he advantage6 of being ba~ed on conventional aqueou6 ~ilver halide photoyraphic chemi6try and provide 6upe~ior in~ula~ing propertie~ u~der relative humidity condition6 commonly encountered duri~g printing.
SUMMARY OF THE TNVENTION
Thi~ invention provides a photosensitive compo~ition adapted or u6e in preparing an elec~ro æt~ti~ printing ma6teL. the ~ompo6ieion con6~6~ing e~entially of a siilYer halide phstog~aphic ~alt : di6persed in an in6ulating pol~meric binder ~ha~ i6 ~wellable in aqueou6 photographic proc~ ing solu-tion~ having a pH higher tha~ approxi~a~ely ~-1/2~
and Letain~ 6ignifi~ant in6ulating prope~ie~ under relative hu~idity condition6 normally enrou~ered during the printing proce~6. The composition ha~
an insulation value 6uch that it will ~upport an apparent macro6copic electric field of ~t least ~ive ~5) volt6/~icron, a~ mea~ured by an electro~tatic 6urface voltage probe two (2) 6econd~ following full charging of it6 surface that ha~ been allowed to equilibrate at 50% relative humidity at 20C for an hour. common photographic gelatin, practically the only medium conventionally u6ed for wet proce66ing.
3s hold~ approximately one (l) volt/micron or le6E after 6~37 equilib~ation u~der the6e te6~ condition~. 5ince the binder i~ swellable under pH condi~io~s high0r than approxi~ately 8-1~2, ConVeA~iOnal aqu~ou~ fiilver halide developi~g 801ution6 can be u6ed to proce66 the ~a~ter for u~e in electro6ea~ic prinei~g.
Copolyme~s of acrylic o~ ~ethac~ylic a~id having a~id number6 in the range of 70 to 160 are a p~e-ferred bi~dar that ~ay be 6elected in p~acticing the inve~ion. The silver halide~binder co~position i6 typically coated onto a condu~ting ~ubstra~e, which ~ay be mounted on a flexible ~upport, for u6e a6 an ele~tro~tatic ma6ter. After ~he ~a6ter i6 imaged ~ith actinic light. the ma6ter i~ developed to contain a ~ er image using conventional aqueous 6ilver halide developing and ~ixing chemistry.
In a 6econd embodi~ent. a diffu6io~ transfer film i8 p~epared by coating the poly~eric binder which contain6 development nuclei onto a conduc~ive 6upport, and o~ercoa~ing ~he binder with a co~ventional 6ilver halide photographic emul6ion. ~he photosen~i~ive element i~ expo6ed and then developed using ~onven-tional difu6ion tran~fer technique~ to p~ovide an imaged elec~rostatic ~a6ter.
A6 u6ed herein. the term ~electrostatic ~aster~ refer6 to the fil~ element that will be u6ed for elec~ro~tatic printing, whether the fil~ element contai~s 6ilve~ pa~ticle~ in the form of the de6ired i~age, and ~hu~ i~ ready for ~he printing proce66, or contain~ eilve~ halide particle6 ~hat yet have to be e~posed and/or developed.
BRIEF DESCRIPTION OF THE DRAWINGS
, , Figure 1 i6 a ~chematic 6ectional view of an electro6tatic printing ~a6ter in which a 6ilver halide photogLap~ic 6alt i~ di~per6ed in the insulating binder to form ~hoto6en6itive layer 1.
Figure 2 6how~ th~ ~a6ter of ~ig. 1 in which a l~te~t i~age ha~ been formed and developed.
FiguEe 3 show~ ~he master of Fig. 2 after the image has been fixed.
Pigure 4 show~ the master of 'Fi~. 3 after bei~g charged.
~igure 5 illu~trate~ the ~a6~er of Fig. 4 in which toner ~article6 have been attracted ~o the charged 6urface.
Figure 6 is a çchematic ~ec~ional view of a ~econd embodiment in ~hich the photo~en6i~ive layrr i8 a diffu6ion t~an6fer film.
Figure 7 6how6 the embodiment of Fig. 6 in which the diffusion tran6fer fil~ ha6 bee~ imaged and development has commenced.
Figure 8 8~0Wfi the embodiment o~ Fig. 7 after developmen~ is complete.
Figur~ 9 ~how~ t~e embodiment of Fig. B
a~ter the ~hotosensitive layer 8 has bee~ remo~ed, at ~; 20 ~hich time it i6 ~eady ~o be used as an electro6tatic master.
:~.
D TAlLED DESCRIPTION OF THE INVENTION
~he u6e of conventional aqueous silvee halide ehotographic ch~mis~ry ideally ser~es ~ha require~ent6 for the preparation of electrostatic printing master~, par~icularly when high refiolution B reguired for high-quality half-tone or con~inuous-to~e aeplication6. Sharp image resolution can be 3G obtained due to the fine qrain size of 6ilver that may be obtained when using aqueous photographic ~hemistry well known i~ the art.
ln~ulating binder6 ~hat ~ay be ~ele~ted in practi~ing the invention are "swellable~ in aqueou~
3~ 601utions having a pH higher than approxi~ately 3~7 8-1/2, typieally in the range of 9 ~o 1~, that a~e com~on ~o conven~ional aqu~ou~ developing ~olueion~
u6ed in ~ilver halide photo~raphy. ~y "~wellable" it i6 ~eant ~hat the binder readily ~ake~ up watel, and indeed 6well~ i~ thi~ pH range ~imilar to gelatin.
~he~ using preferred polymer6 de~cribed hereinaftQrO
6welli~ accompll~hed by ionizing acidic groups ~u~ually carborylic acid group6 ~hat are chemically bonded to the in~ulating binder) by ba6ic solution6 at a pH o~ approximately 8.5 or higheE. This characteri6tic permit6 the aqueous developer (reduci~g) ~olution to come in~o intimate contact wi~h the ~il~er hal~de. When negative wozking 6ilver halide emul6ion6 are used, the expo~ed silver halide 5 i6 eeduced ~y developer ~olution6 to metallic ~ilver and complexing agents di6601ve the u~expo6ed ~ilver ~alide salt. When po~itive working ~ilver halide emul~ions are used (e.g. tho~e prepared by such well-kno~n ~echniques a~ 601ariza~ion or ~hemical fogging) the unexpo~ed 6ilver halide 1~ re~uced to metallic silveE and the ~xpo~ed ~ilver halide removed.
I~ the embodime~ des~ribed in grea~er detail hereinafter in which negative workinq ~il~er halide is di6per6ed in the i~ulati~g binder~ ~ro-vided by ~he invention, developer above approximately pH 8.5 6welle the binder and reduces expo6ed ~ilver halide ~o ~etallic ~ilve~ ~nd complexing agent6, usually in a fixer eolu~ion, remove unexpo6ed ~ilver halide. I~ ~he diffu6ion transfer em~odi~ent where negative working photosensit~ve 6ilver halide ~6 in an emulsion layer (u6ually gelatin) that i6 ~eparate from the insulating binder containing a fine di6per-~ion of development nu~lei, developer solu~ion having a pH above appeoxi~ately 8.5 swell6 both t~e e~ul~ion 3'~
layer and insulaeing binder layer provided by this invention~ ~hereby developing tAe expo~d 6ilve~
h~lide ~o ~etallic silver in the emul~ion layer and difisolvi~g ~he unexpo6ed ~ilYer halide with complexing agentfi (i'6ilver 601Yents"3. The complexed unexpo6ed 6ilver halide then dif~u6es into the ~wollen binder l~yer wherein t~e s~lver ions are selectively Ieduced to 6ilver ~etal on the development nu~'Lei.
Although the in6ulaei~g binders are lQ 6wellable in the developiny 601ution, ~he in6ula~ing properties do ~ot drastically deteriorate a6 ehose of g~latin do under typical humidity conditions en~oun-tered i~ the ~orkplace. As a consequence, the binders will retain an applied cha~ge durin~ slectrostatic lS printing and it i6 not nece66ary to provide ~pecial humidity control~ or dry the ma6te.r be~ore each printing cycle. a6 would be ~eces6ary u6ing a gelatin bind~r 0 The binder~ generally are characte~ized a6 bei~g capable of 6up~0rti~g an apparent macroscopic electric ~ie}d of at lea~t 5 volt~ per micron. and preferably at lea6~ 30 volts per micron, as mea~ured by a~ electros~atic 6urface voltage probe two (2) second6 ollowing ~ull charging of the 6urface af~er the surface has been allowed ~o equilibra~e. and thus ab60Eb moi~ture, at 50% relative humidity and 20OC.
Equilibration for testing purpose6 will nor~ally occur within approxima~ely 60 minutes. In contrast, gelatin is significantly l~ferior and exhibits an apparen~ ~acro6copic electric field in the order of approximately one ~l~ volt per micron or le86 under thi~ test procedure.
Ie has been found that ~ynthetic polymers having an acid number o app~oximaeely 70 to 160 are par~i~ularly u~eful in praclicing the invention. A
~3~
preferred cla~6 of poly~er~ contain~ 10 ~o 25~ by weigh~ of ~rylic or meehacrylic acid ~o impart swellabili~y. ~he polymer typically ~ill al~o con~aih ~tyrene. or oth~r aromatic ~ono~ers, ~hat S are ~ot compatible with water, and ~hu~ resder the polymer le~ hydrophilic to moi~ur~ in the air~
Generally, the polymer will al~o con~ain ~ono~er6.
~uch a6 appropriate acrylic or methacrylic e~ter6, ~hat ~ontribute to fil~ clarity, flexibili~y, eough ne~, eroces6ibility. e~c. Other co~ono~ers~ ~uch a~
alken~6 havi~g 2 to 12 carbon ato~ aloolefin6, vinyl acetate, vinyl ether6 having 3 to 12 carbon atomsO methacrylamide. and the like can be similarly u~eful.
Preferred polymer~ ~re copolymer~ ~ontaini~g ~yrene and acrylic or ~ethacrylic acid mono~ers, and preferably also an acrylic or ~ethacrylic e6ter mo~omer. Polymer6 containing 25 to 35% by weight styrene, 10 to 25~ by ~eiyht acrylic or me~hacrylic ac;d, with ~e remainder compri6i~g a~rylic or ~ethacrylic e~teL6, are pa~ticularly pre erred. The ~ole~ular weight of the preferred copolymer~ will typically b~ in the range of 25,000 to 150,000.
'rhese polymer~ a~e compatible with silver ~alide di~per~ion~, will forr~ teasonably durable film6 that have clarity, and are readily available f~om commercial ~ou~ce6, or can be made using conventional technique6 6uch a6 free radical polymerization in ~u~pen~ion or emul~ion. Equi~alent polymer~ that will be useful in practicing the invention will be readily apparent to ~ho~e ~killed in the art. These polyme~s include acrylic acid and ~thacrylic acid polymer6 and copoly~er~, and include commercially available polymer6 ~uch as Ca~bo6et~ 525 an~ Car~s6et~
526 ~anufactured by 9. F. Goodri~h Company, and Joncryl~ ~7 manufactured by John60n ~ Johnson.
A preferred cla~6 of polymer6 consti~ute6 terpolymer~ and ~etrapolymer~ of (1) a ~tyrene-type ~onomer, (2) a~ a~rylate-type ~o~omer, ~nd (3~ an un6atu~a~ed carboxyl con~aining ~ono~er. The ~ir~t ~omponen~ lend~ hardne~s and moisture re~istance to the polymer, the ~econd, flexib~lity and pla~ticity to the polymer backbone; and the third, alkali-wellability. The ~tyrene-type ~onomer will ~y~ically be 6tyrene, an alpha-6ubstituted ~tyrene havi~g a 1 to S carbon alkyl group, and tho~e wherein th~ benzene ring ha6 f~nctional 6ubstitu~ed group~
6uch a6 ~itro. alko~y, acyl. carboxy, 6ulpho, or halo.
wi~h 6imple compound~ ~uch as 6tyrene, alphamethyl 6tyrene, para-~ethyl 6tyrene and para-t-bu~yl styrene being prefeered. The acrylate-type component i.ncludes alkyl and hydroxyalkyl acrylate6 and methacrylate6 wherein the alkyl group ha6 from 1 to 12, preferably ~rom 1 to 6 carbon atoms 6uch a6 methyl methacryla~e, ethyl~ethacrylate, ethyl acrylate, hydroxypropyl methacryl~te, ~ydroxyethyl methacrylate and hydroxy-~thyl aerylate, and mixtu~e6 ~hereof. The un~aturated carboxyl-containing ~onomer will typically be a mono~er having from ~ to 15 ~arbon atom6, prefeeably 3 to 6. and includes cinnamic acid. ~ro~onic acid, sorbic a~id, i~aconic acid, maleic acid, fu~aric acid, or more preîerably acrylic or methacryli~ acid, theie corre~ponding hal~ e6ter or the corresponding anhydr ide .
~hen thi6 clas6 o polymer i~ ~elected in ~racticing the invention~ ~he ratio of ~he three monome~ component6 i6 ~elected ~uch that the eonduc-tive film element ha6 the Pollowing propertie6 ~he ~ilver halide. when incorporated into the conductive Pilm ~lement, i8 proce~ible by conventio~ai aqueou6 photographic technique6: the electro6~a~ic ma6ter ~3~3~7 ~ade ~heIef~om ~e~ain6 applied cha~ge6 in the ~onsilve~ ~ ea6 under am~ieRt relative humidi~y condition6; and the electro~ta~ic ~a~ter i5 flexible and durable, but not ~acky. Typi~al proportions u6ed to a~hieve the~e result~ are shown in Table lo Binder Com~onent Broad Range Preferred Ra~g~
~ei~t %) (weiqht~
~tyrene-type 10-50 25-35 10 As~ylate-type 0-85 40-65 Ca~boxylic 5-50 10-2 acid-type Poly~e~ within ~hi6 class also generally offer the ~dva~tage o~ being insensitive to I60par~, the co~mGnly u6ed cacrier employed in liquid toning ~y8 te~6.
In~ulating polymeric binders described above are made by conventional free-radical polyme i2ation ~20 ~ech~ique6~ a6 illu~trated in the examples. The6e :polyme~ are ~oluble in basic solution~ and can be coated fro~ aqueou6 solutions of triethylamine.
a~onia~ or ~o~as~ium hydroxide, and ~he like. The~e polymers are ~ompatible with silver halide disper6ions and will fo~m rea60nably durable films ~hat have clar~ty. It may be de~ired to modify the binder (cros61ink, ha~den, plasticize. adju~t acidity, etc.) prio~ to aqueous photographic processing, and thereby ~ont~ol ~welling or improve durabili~y. Various modifying agents may be added for these pu~poses.
~ypical modifying agent~ include aldehydes, multi-functional aziridine6, and epoxides. The diglycidyl ethe~ of 1.4-butanediol is a preferred modifying ;agent for this class o~ poly~ers in prac~icing ~he 3~ invention.
' .
~ ~}~ 37 Equivalent polymer6 that achieve the balance of propertie~ de~c~ibed above will be apparent to thofie skilled i~ ~he art. and ~ay be selected in practicing the invention.
S The light 6en6itive 6ilver halide 6elec~ed for ~i6per6ion in the binder can be any of ~he well-known 6alt6 u6ed in pho~ographic application6.
Representati~e u6eful 6alt6 include 6ilver ~hloride, ~ilver bromide. 6il~er iodide, silye ~hlorobromide, ~ilver iodobromide, and 6ilver ~hloroiodobromide, either ~ingly or in ~ix~ure~. Precipitation of the halide i~ carried out in conventional ~anner in gela~in. The amount o~ gelatin pre~ent 6hould be limited~ or 6ub6equently reduced by rinsin~, to avoid d~feating purpo~e6 of the invention. Generally, levels of gelatin a6 high a6 3 to 15 gram6 per mole of 6ilver can be tolerated in the elect~o~tatic printing ma6ter6. without adver6e effect.
: Grain ~ize di~tribution and ~en6itizatio~ o~
the 6ilver halide can be controlled to adapt the ~ilver halide6 for ~he 6alec~ed cla~6 of pho~ographic proce~a, includi~g general continuou6 tone, X-ray, lithographic, microphotographic, direct posi~ive, and t~e like. Ordinarily, the 6ilver sale di~per6ion~
will be ~en~itized with ~o~ventional co~pound6 ~uch a~ sulur, gold, rhodlum, selenium and the like, or with o~ganic sen6itizing dye6 6uch a~ cyanine, 1.1'-diethyl-4,4'-cy~nine iodide, methine and polymethine cyanine dyes, kryptocyanine6, ~erocyanine~, and the like. Other additive6 commonly employed in 6ilver halide photographi~ com206ition6, may al60 be pre6en~
if de6ired.
To prepare the di6per~ion of ~ilver halide in the in6ulating polymeric binder, the binder i6 conveniently fir~t di6~01ved in an aqueou6 ~olution - . ~
`fil5~
containing amine6. 6uch a6 a~onia or triethyl amine.
If de~ired, a~ alcohol, 6uch aç me~ha~ol, ethanol, or i60propanol, ~ay be added ~o aid in 601ubilizing the polymer. ~e~one6, ~uch a~ methyl e~hyl keto~e, may 5 be u6ed a~ a co~olvent. ~ aqueou6 di6persio~ of the silver halide ~al~ hen added to the di~ olved binder in the de6ired quanti~ie6. The re6peceive portion~ o silver halide tD binder will depend o~
detail6 of the application~ but ~ill generally be 10 6uch that 6urface of the ma~te~ immediately above the developed 6ilYer will di~charge ~iqnificantly fa~er tha~ area6 devoid of ~ilver. ~eigh~ ratio~ of 6ilver to polymeri~ binder in the ranys of 0.5:1 to 3:1 will typically provide u6eful recult6. A p~eferred range i~ 1.7:1 to 2.3:1.
The polymeric binder containing ehe 6ilver halide i6 usually applied to a conductive substrate a6 a 601ution or di6persion in a carrier ~olvent, u~ually a~ aqueou6 601ution co~taining ba6ic amine6 o~ 60dium o~ pota6sium hydro~ide a~ de6cribed above.
The eoa~in~ procedure may be any conven~ional one including 6p~ayin~, brus~i~g. applying by a roller or a~ er~ion coater, flowing over the ~urface, picki~g up by immersion, ~pin coatiny. air-knife coa~ing, wire~bar coating or any other 6uitable mean6. The film thicknes6 can be adju6ted accordingly and after ; drying i~ u6ually abou~ O.OZ to about 0.3 mil6 ~0.5-7.5 ~icron~). p~eerably about 0.04 to about 0.20 ~il~ -5.~ micron6). Depending on the application, the conductive 6upport may be a ~etal ~late, such a~ aluminum. copper. zinc, 6ilver or the like; a conductive polymeric film; a 6uppor~ such a6 paper, gla6~. synthetic re6in and the like which ha6 .~ been coated with a metal, metal oxide. or ~etal 3s halide by vapor depo6i~ion or chemical depo6ition:
.
-- ~ 3~ 3 ~
a ~uppor~ which has been coated with a conductive ~olymer: or a 6uppor~ which ha~ been Goated wieh a polyme~ic binder con~aining a metal, metal oxide~
~etal halide, conduc~ive polyme~, carbon, or other conductive filler~.
In addi~ion to Gomponen~ deficrib@d abo~e, various ~onven~ional photogLaphi~ ~dditive~, e.g., de~eloping aqent6. ~uper additive~, antifoggant6, ~oating aid6 6uch a6 6~ponin, alkylaryl6ulfonic acid6 lo or ~ul~oalkylæuccinic aeid6; plasticizers 6uch glycerol or l,5-pen~anediol: anti~tatic agent6: agen~
to p~eve~t the Por~ation of s~ot~: antihalation dye6;
underlayer~, ~ubbing or backing laye~; a~d the like ~ay be added ~o the master a~ appropriate. Po6it~ve image6 ~ay be obtained by rever6al proce66ing of the 6ilver halide u6ing either light fogging or a chemical fogging agent: or by u~ing 6ilver halide emul6ion6 that give direct po6itive image6 UBiDg the prefoggi~g technique. Di~ect po~i~ive emul6ion6 have been de6cribed in Leer~maker U.5. Pat. No. 2,184,0l3.
Illing6wor~h U.S. Pat. No. 3,50l,307 and el6ewhere.
Referring now ~o the drawing6. Figure 1 depic~ an elect~ostatic printinq ma~ter in which hoto6en~itive layer l con~ain6 ~en6itized ~ilve~
halide di~per~ed in t~e in~ula~i~g polymeric binder in acco~dance with the invention. Layer 1 i6 generally between 0.5 and 7.5 ~i~ron6 in thickne~, but ~he thickne6~ can be decrea6ed or increa6ed for ~he 6peeific intended application. A thin layer 2 of an adhe6ion promoter ~uch a6 gelatin, which i6 o~ional, aid6 adherence of the phoeo~en~i~ive layer to the ~ondue~ing 6ub~trate 3, whi~h in ~uen i~
mounted on 6uppo~ting 6u~strate ~
The ~a6ter i~ expo6ed imagewi6e u6ing any of the proceduce6 commonly u6ed with ~ilver halide .
~L3~ l37 pho~ographic material6. such a~ by imaging with ac~ini~ light, a cathode ray ~ube, or la~er. ~or - ne~ative-working emul6ion6 ehe latent image 5 i~
then developed by reduc~ng ~he expo6ed ~ilver halide parti~le6 to metallic 6ilver u6ing a con~entional aqueou6 developing solueion. a6 illu6~rated in Figure 2. A conventional aqueou~ fixing solution, such a~ 60dium ~hio6ulfate, i6 ~hen u~ed to remoY~
the unexpo6~d 6ilver halide particles, as illu~trated ~o in ~igure 3. The deYeloped ma6~er i6 then ready for tbe electEo6tati~ printi~g proce66.
Figure 4 illu6trate~ t~e master of Fiqure 3 after it has been cha~ged by a corona discharge ~hat depo~ited po6itive charge6 6 on the ma6ter 6urface.
The area of the film that contain6 ~ilver S pro~ide~
a pathway for overlying charges to pa66 to ground, thus forming a latent image of charges that remain on : the master ~urface. Al~ernatively. charging can be accompli~hed with the u6e of a negative corona di~charge, 6hielded ~orotron~ ~corotron, radioactive 60urce. ~ontact electrode6 ~uch a6 eleet~ically bia6ed 6emiconductive rubber roller~, and ehe like.
The latent i~age i6 ~hen develop~d witb liquid or dry toner 7 of the oppo~ite polariey, a6 :~ 2~ illu6trated ~n Figure 5. Cascade, ma~e~ic bru6h, powder cloud, liquid, r~agne-dry and we~ting develop-ment te~hnique6 are 6uitable. Repre~enta~ive dry ~oner~ that may be u6ed include Kodak Ektaprint K
toner, Hitachi HI-Toner ~MT-414, Cano~ NP-350F ~oner, 30 and To6hiba T-50P toner. Exa~ple& of ~uitable liquid toner6 are Savin 24 toner~ Canon LBP ~one~ and Jame~
River Graphics TlB18 toner. The laten~ image 60 developed ("toned") i6 tran6ferred to the usual ~ub6trate, typically paper. where it i6 fixed in 3S conventional ~a6hion.
.
1'1 Figure6 6 through 9 illu6trate a 8econd embodi~en~ wherQi~ co~ventional diffu6ion ~an6fe technique~ 6u~h a ~ho6e de~cribed in U.S. Patent
BACKGROUND OF_TH~ _NVE~ TION
Thl6 inventio~ relatefi to elec~rostatic ~rinti~g and, more par~icularly, ~o a~ i~proved electrostatic printin~ ~a~ter adapted ~or the u~e o co~ven~ional ~ilYer halide ~hotogra~hic technigue~
during ~rep~ration of the ~a6teY ~or pri~ti~g.
; Ele~tro~tatic p~inti~g i6 ~ell-know~ ~n the art and ha6 been propo~ed ae a~ alternatiYe ~o ot~er : ~ri~ting te~hnique6. In one method o~ electEosta~ic ; prin~ing, one f ir~ ~repare~ a "~a~er~ tha~ i~
capable o~ ~electively holding electro~ta~ic ~harge$
to for~ the desi~ed i~age. The master i~ expo~ed to a corona di6charye that forms a latent elec~rostatic image, and contacted with dry or liquid toner of the oppo6ite electrostatic charge to develoe the i~age.
The toned image i~ then tran~ferred ~o a sub~rate, typically paperO where the toner i6 fu6ed ev fix ~he image, a~d the ~a~ter i~ retur~ed for the ~e~t printing cycleO
It has been 6ugge6ted in U.S. Patent 4.069,759 that an i~roved electro6ta~ic p~i~ting ~a~ter ca~ be fabricated by disper~ing a ~onve~tio~al 6ilve~ halide photographic ~alt in an in6ulating polymer (e.g., gelati~)~ and coa~ing the di~persion on a conducting substrate. The coating i8 expo6ed : i~agewi6e, and i~ developed to ~au~e ~he exposed 6ilve~ halide to be reduced to metalli~ ~ilver~ The 30 u~expo6ed ~ilveE halide ~ then di~601Yed and ~emoved from the coating to fix the i~age. ~hile the ~aster 6ugge6eed in U.S. Patent 4,069,7Sg offers many advan-tage6, and per~it6 the u~e of ~onven~ib~al aqueous ~ er halide photographic che~istry whe~ gelatin iB
35 ~ele~ted a6 the in6ulating polym2r, it has bee~ Pound .
~ t7 tha~ gelatin is tGo highly 6en~itive to humidi~y to hav~ prac~ical application in a typical workplace.
~elatin rapidly ab60rbs ~oi6ture ro~ the ai~ and at ~odera~e to high humiditi~6 no lo~gel fun~tio~s a~ a~
in~ulaSing medium, bu~ provide~ a ~onclucti~e path ~hat g~ound~ ~ur ace ~hargei impoced on the master during the electro~ta~ic prin~ing ~roce~.
Thu6. ~here i~ a need for ~n improved electro~tatic printing ma6ter that will offer ~he advantage6 of being ba~ed on conventional aqueou6 ~ilver halide photoyraphic chemi6try and provide 6upe~ior in~ula~ing propertie~ u~der relative humidity condition6 commonly encountered duri~g printing.
SUMMARY OF THE TNVENTION
Thi~ invention provides a photosensitive compo~ition adapted or u6e in preparing an elec~ro æt~ti~ printing ma6teL. the ~ompo6ieion con6~6~ing e~entially of a siilYer halide phstog~aphic ~alt : di6persed in an in6ulating pol~meric binder ~ha~ i6 ~wellable in aqueou6 photographic proc~ ing solu-tion~ having a pH higher tha~ approxi~a~ely ~-1/2~
and Letain~ 6ignifi~ant in6ulating prope~ie~ under relative hu~idity condition6 normally enrou~ered during the printing proce~6. The composition ha~
an insulation value 6uch that it will ~upport an apparent macro6copic electric field of ~t least ~ive ~5) volt6/~icron, a~ mea~ured by an electro~tatic 6urface voltage probe two (2) 6econd~ following full charging of it6 surface that ha~ been allowed to equilibrate at 50% relative humidity at 20C for an hour. common photographic gelatin, practically the only medium conventionally u6ed for wet proce66ing.
3s hold~ approximately one (l) volt/micron or le6E after 6~37 equilib~ation u~der the6e te6~ condition~. 5ince the binder i~ swellable under pH condi~io~s high0r than approxi~ately 8-1~2, ConVeA~iOnal aqu~ou~ fiilver halide developi~g 801ution6 can be u6ed to proce66 the ~a~ter for u~e in electro6ea~ic prinei~g.
Copolyme~s of acrylic o~ ~ethac~ylic a~id having a~id number6 in the range of 70 to 160 are a p~e-ferred bi~dar that ~ay be 6elected in p~acticing the inve~ion. The silver halide~binder co~position i6 typically coated onto a condu~ting ~ubstra~e, which ~ay be mounted on a flexible ~upport, for u6e a6 an ele~tro~tatic ma6ter. After ~he ~a6ter i6 imaged ~ith actinic light. the ma6ter i~ developed to contain a ~ er image using conventional aqueous 6ilver halide developing and ~ixing chemistry.
In a 6econd embodi~ent. a diffu6io~ transfer film i8 p~epared by coating the poly~eric binder which contain6 development nuclei onto a conduc~ive 6upport, and o~ercoa~ing ~he binder with a co~ventional 6ilver halide photographic emul6ion. ~he photosen~i~ive element i~ expo6ed and then developed using ~onven-tional difu6ion tran~fer technique~ to p~ovide an imaged elec~rostatic ~a6ter.
A6 u6ed herein. the term ~electrostatic ~aster~ refer6 to the fil~ element that will be u6ed for elec~ro~tatic printing, whether the fil~ element contai~s 6ilve~ pa~ticle~ in the form of the de6ired i~age, and ~hu~ i~ ready for ~he printing proce66, or contain~ eilve~ halide particle6 ~hat yet have to be e~posed and/or developed.
BRIEF DESCRIPTION OF THE DRAWINGS
, , Figure 1 i6 a ~chematic 6ectional view of an electro6tatic printing ~a6ter in which a 6ilver halide photogLap~ic 6alt i~ di~per6ed in the insulating binder to form ~hoto6en6itive layer 1.
Figure 2 6how~ th~ ~a6ter of ~ig. 1 in which a l~te~t i~age ha~ been formed and developed.
FiguEe 3 show~ ~he master of Fig. 2 after the image has been fixed.
Pigure 4 show~ the master of 'Fi~. 3 after bei~g charged.
~igure 5 illu~trate~ the ~a6~er of Fig. 4 in which toner ~article6 have been attracted ~o the charged 6urface.
Figure 6 is a çchematic ~ec~ional view of a ~econd embodiment in ~hich the photo~en6i~ive layrr i8 a diffu6ion t~an6fer film.
Figure 7 6how6 the embodiment of Fig. 6 in which the diffusion tran6fer fil~ ha6 bee~ imaged and development has commenced.
Figure 8 8~0Wfi the embodiment o~ Fig. 7 after developmen~ is complete.
Figur~ 9 ~how~ t~e embodiment of Fig. B
a~ter the ~hotosensitive layer 8 has bee~ remo~ed, at ~; 20 ~hich time it i6 ~eady ~o be used as an electro6tatic master.
:~.
D TAlLED DESCRIPTION OF THE INVENTION
~he u6e of conventional aqueous silvee halide ehotographic ch~mis~ry ideally ser~es ~ha require~ent6 for the preparation of electrostatic printing master~, par~icularly when high refiolution B reguired for high-quality half-tone or con~inuous-to~e aeplication6. Sharp image resolution can be 3G obtained due to the fine qrain size of 6ilver that may be obtained when using aqueous photographic ~hemistry well known i~ the art.
ln~ulating binder6 ~hat ~ay be ~ele~ted in practi~ing the invention are "swellable~ in aqueou~
3~ 601utions having a pH higher than approxi~ately 3~7 8-1/2, typieally in the range of 9 ~o 1~, that a~e com~on ~o conven~ional aqu~ou~ developing ~olueion~
u6ed in ~ilver halide photo~raphy. ~y "~wellable" it i6 ~eant ~hat the binder readily ~ake~ up watel, and indeed 6well~ i~ thi~ pH range ~imilar to gelatin.
~he~ using preferred polymer6 de~cribed hereinaftQrO
6welli~ accompll~hed by ionizing acidic groups ~u~ually carborylic acid group6 ~hat are chemically bonded to the in~ulating binder) by ba6ic solution6 at a pH o~ approximately 8.5 or higheE. This characteri6tic permit6 the aqueous developer (reduci~g) ~olution to come in~o intimate contact wi~h the ~il~er hal~de. When negative wozking 6ilver halide emul6ion6 are used, the expo~ed silver halide 5 i6 eeduced ~y developer ~olution6 to metallic ~ilver and complexing agents di6601ve the u~expo6ed ~ilver ~alide salt. When po~itive working ~ilver halide emul~ions are used (e.g. tho~e prepared by such well-kno~n ~echniques a~ 601ariza~ion or ~hemical fogging) the unexpo~ed 6ilver halide 1~ re~uced to metallic silveE and the ~xpo~ed ~ilver halide removed.
I~ the embodime~ des~ribed in grea~er detail hereinafter in which negative workinq ~il~er halide is di6per6ed in the i~ulati~g binder~ ~ro-vided by ~he invention, developer above approximately pH 8.5 6welle the binder and reduces expo6ed ~ilver halide ~o ~etallic ~ilve~ ~nd complexing agent6, usually in a fixer eolu~ion, remove unexpo6ed ~ilver halide. I~ ~he diffu6ion transfer em~odi~ent where negative working photosensit~ve 6ilver halide ~6 in an emulsion layer (u6ually gelatin) that i6 ~eparate from the insulating binder containing a fine di6per-~ion of development nu~lei, developer solu~ion having a pH above appeoxi~ately 8.5 swell6 both t~e e~ul~ion 3'~
layer and insulaeing binder layer provided by this invention~ ~hereby developing tAe expo~d 6ilve~
h~lide ~o ~etallic silver in the emul~ion layer and difisolvi~g ~he unexpo6ed ~ilYer halide with complexing agentfi (i'6ilver 601Yents"3. The complexed unexpo6ed 6ilver halide then dif~u6es into the ~wollen binder l~yer wherein t~e s~lver ions are selectively Ieduced to 6ilver ~etal on the development nu~'Lei.
Although the in6ulaei~g binders are lQ 6wellable in the developiny 601ution, ~he in6ula~ing properties do ~ot drastically deteriorate a6 ehose of g~latin do under typical humidity conditions en~oun-tered i~ the ~orkplace. As a consequence, the binders will retain an applied cha~ge durin~ slectrostatic lS printing and it i6 not nece66ary to provide ~pecial humidity control~ or dry the ma6te.r be~ore each printing cycle. a6 would be ~eces6ary u6ing a gelatin bind~r 0 The binder~ generally are characte~ized a6 bei~g capable of 6up~0rti~g an apparent macroscopic electric ~ie}d of at lea~t 5 volt~ per micron. and preferably at lea6~ 30 volts per micron, as mea~ured by a~ electros~atic 6urface voltage probe two (2) second6 ollowing ~ull charging of the 6urface af~er the surface has been allowed ~o equilibra~e. and thus ab60Eb moi~ture, at 50% relative humidity and 20OC.
Equilibration for testing purpose6 will nor~ally occur within approxima~ely 60 minutes. In contrast, gelatin is significantly l~ferior and exhibits an apparen~ ~acro6copic electric field in the order of approximately one ~l~ volt per micron or le86 under thi~ test procedure.
Ie has been found that ~ynthetic polymers having an acid number o app~oximaeely 70 to 160 are par~i~ularly u~eful in praclicing the invention. A
~3~
preferred cla~6 of poly~er~ contain~ 10 ~o 25~ by weigh~ of ~rylic or meehacrylic acid ~o impart swellabili~y. ~he polymer typically ~ill al~o con~aih ~tyrene. or oth~r aromatic ~ono~ers, ~hat S are ~ot compatible with water, and ~hu~ resder the polymer le~ hydrophilic to moi~ur~ in the air~
Generally, the polymer will al~o con~ain ~ono~er6.
~uch a6 appropriate acrylic or methacrylic e~ter6, ~hat ~ontribute to fil~ clarity, flexibili~y, eough ne~, eroces6ibility. e~c. Other co~ono~ers~ ~uch a~
alken~6 havi~g 2 to 12 carbon ato~ aloolefin6, vinyl acetate, vinyl ether6 having 3 to 12 carbon atomsO methacrylamide. and the like can be similarly u~eful.
Preferred polymer~ ~re copolymer~ ~ontaini~g ~yrene and acrylic or ~ethacrylic acid mono~ers, and preferably also an acrylic or ~ethacrylic e6ter mo~omer. Polymer6 containing 25 to 35% by weight styrene, 10 to 25~ by ~eiyht acrylic or me~hacrylic ac;d, with ~e remainder compri6i~g a~rylic or ~ethacrylic e~teL6, are pa~ticularly pre erred. The ~ole~ular weight of the preferred copolymer~ will typically b~ in the range of 25,000 to 150,000.
'rhese polymer~ a~e compatible with silver ~alide di~per~ion~, will forr~ teasonably durable film6 that have clarity, and are readily available f~om commercial ~ou~ce6, or can be made using conventional technique6 6uch a6 free radical polymerization in ~u~pen~ion or emul~ion. Equi~alent polymer~ that will be useful in practicing the invention will be readily apparent to ~ho~e ~killed in the art. These polyme~s include acrylic acid and ~thacrylic acid polymer6 and copoly~er~, and include commercially available polymer6 ~uch as Ca~bo6et~ 525 an~ Car~s6et~
526 ~anufactured by 9. F. Goodri~h Company, and Joncryl~ ~7 manufactured by John60n ~ Johnson.
A preferred cla~6 of polymer6 consti~ute6 terpolymer~ and ~etrapolymer~ of (1) a ~tyrene-type ~onomer, (2) a~ a~rylate-type ~o~omer, ~nd (3~ an un6atu~a~ed carboxyl con~aining ~ono~er. The ~ir~t ~omponen~ lend~ hardne~s and moisture re~istance to the polymer, the ~econd, flexib~lity and pla~ticity to the polymer backbone; and the third, alkali-wellability. The ~tyrene-type ~onomer will ~y~ically be 6tyrene, an alpha-6ubstituted ~tyrene havi~g a 1 to S carbon alkyl group, and tho~e wherein th~ benzene ring ha6 f~nctional 6ubstitu~ed group~
6uch a6 ~itro. alko~y, acyl. carboxy, 6ulpho, or halo.
wi~h 6imple compound~ ~uch as 6tyrene, alphamethyl 6tyrene, para-~ethyl 6tyrene and para-t-bu~yl styrene being prefeered. The acrylate-type component i.ncludes alkyl and hydroxyalkyl acrylate6 and methacrylate6 wherein the alkyl group ha6 from 1 to 12, preferably ~rom 1 to 6 carbon atoms 6uch a6 methyl methacryla~e, ethyl~ethacrylate, ethyl acrylate, hydroxypropyl methacryl~te, ~ydroxyethyl methacrylate and hydroxy-~thyl aerylate, and mixtu~e6 ~hereof. The un~aturated carboxyl-containing ~onomer will typically be a mono~er having from ~ to 15 ~arbon atom6, prefeeably 3 to 6. and includes cinnamic acid. ~ro~onic acid, sorbic a~id, i~aconic acid, maleic acid, fu~aric acid, or more preîerably acrylic or methacryli~ acid, theie corre~ponding hal~ e6ter or the corresponding anhydr ide .
~hen thi6 clas6 o polymer i~ ~elected in ~racticing the invention~ ~he ratio of ~he three monome~ component6 i6 ~elected ~uch that the eonduc-tive film element ha6 the Pollowing propertie6 ~he ~ilver halide. when incorporated into the conductive Pilm ~lement, i8 proce~ible by conventio~ai aqueou6 photographic technique6: the electro6~a~ic ma6ter ~3~3~7 ~ade ~heIef~om ~e~ain6 applied cha~ge6 in the ~onsilve~ ~ ea6 under am~ieRt relative humidi~y condition6; and the electro~ta~ic ~a~ter i5 flexible and durable, but not ~acky. Typi~al proportions u6ed to a~hieve the~e result~ are shown in Table lo Binder Com~onent Broad Range Preferred Ra~g~
~ei~t %) (weiqht~
~tyrene-type 10-50 25-35 10 As~ylate-type 0-85 40-65 Ca~boxylic 5-50 10-2 acid-type Poly~e~ within ~hi6 class also generally offer the ~dva~tage o~ being insensitive to I60par~, the co~mGnly u6ed cacrier employed in liquid toning ~y8 te~6.
In~ulating polymeric binders described above are made by conventional free-radical polyme i2ation ~20 ~ech~ique6~ a6 illu~trated in the examples. The6e :polyme~ are ~oluble in basic solution~ and can be coated fro~ aqueou6 solutions of triethylamine.
a~onia~ or ~o~as~ium hydroxide, and ~he like. The~e polymers are ~ompatible with silver halide disper6ions and will fo~m rea60nably durable films ~hat have clar~ty. It may be de~ired to modify the binder (cros61ink, ha~den, plasticize. adju~t acidity, etc.) prio~ to aqueous photographic processing, and thereby ~ont~ol ~welling or improve durabili~y. Various modifying agents may be added for these pu~poses.
~ypical modifying agent~ include aldehydes, multi-functional aziridine6, and epoxides. The diglycidyl ethe~ of 1.4-butanediol is a preferred modifying ;agent for this class o~ poly~ers in prac~icing ~he 3~ invention.
' .
~ ~}~ 37 Equivalent polymer6 that achieve the balance of propertie~ de~c~ibed above will be apparent to thofie skilled i~ ~he art. and ~ay be selected in practicing the invention.
S The light 6en6itive 6ilver halide 6elec~ed for ~i6per6ion in the binder can be any of ~he well-known 6alt6 u6ed in pho~ographic application6.
Representati~e u6eful 6alt6 include 6ilver ~hloride, ~ilver bromide. 6il~er iodide, silye ~hlorobromide, ~ilver iodobromide, and 6ilver ~hloroiodobromide, either ~ingly or in ~ix~ure~. Precipitation of the halide i~ carried out in conventional ~anner in gela~in. The amount o~ gelatin pre~ent 6hould be limited~ or 6ub6equently reduced by rinsin~, to avoid d~feating purpo~e6 of the invention. Generally, levels of gelatin a6 high a6 3 to 15 gram6 per mole of 6ilver can be tolerated in the elect~o~tatic printing ma6ter6. without adver6e effect.
: Grain ~ize di~tribution and ~en6itizatio~ o~
the 6ilver halide can be controlled to adapt the ~ilver halide6 for ~he 6alec~ed cla~6 of pho~ographic proce~a, includi~g general continuou6 tone, X-ray, lithographic, microphotographic, direct posi~ive, and t~e like. Ordinarily, the 6ilver sale di~per6ion~
will be ~en~itized with ~o~ventional co~pound6 ~uch a~ sulur, gold, rhodlum, selenium and the like, or with o~ganic sen6itizing dye6 6uch a~ cyanine, 1.1'-diethyl-4,4'-cy~nine iodide, methine and polymethine cyanine dyes, kryptocyanine6, ~erocyanine~, and the like. Other additive6 commonly employed in 6ilver halide photographi~ com206ition6, may al60 be pre6en~
if de6ired.
To prepare the di6per~ion of ~ilver halide in the in6ulating polymeric binder, the binder i6 conveniently fir~t di6~01ved in an aqueou6 ~olution - . ~
`fil5~
containing amine6. 6uch a6 a~onia or triethyl amine.
If de~ired, a~ alcohol, 6uch aç me~ha~ol, ethanol, or i60propanol, ~ay be added ~o aid in 601ubilizing the polymer. ~e~one6, ~uch a~ methyl e~hyl keto~e, may 5 be u6ed a~ a co~olvent. ~ aqueou6 di6persio~ of the silver halide ~al~ hen added to the di~ olved binder in the de6ired quanti~ie6. The re6peceive portion~ o silver halide tD binder will depend o~
detail6 of the application~ but ~ill generally be 10 6uch that 6urface of the ma~te~ immediately above the developed 6ilYer will di~charge ~iqnificantly fa~er tha~ area6 devoid of ~ilver. ~eigh~ ratio~ of 6ilver to polymeri~ binder in the ranys of 0.5:1 to 3:1 will typically provide u6eful recult6. A p~eferred range i~ 1.7:1 to 2.3:1.
The polymeric binder containing ehe 6ilver halide i6 usually applied to a conductive substrate a6 a 601ution or di6persion in a carrier ~olvent, u~ually a~ aqueou6 601ution co~taining ba6ic amine6 o~ 60dium o~ pota6sium hydro~ide a~ de6cribed above.
The eoa~in~ procedure may be any conven~ional one including 6p~ayin~, brus~i~g. applying by a roller or a~ er~ion coater, flowing over the ~urface, picki~g up by immersion, ~pin coatiny. air-knife coa~ing, wire~bar coating or any other 6uitable mean6. The film thicknes6 can be adju6ted accordingly and after ; drying i~ u6ually abou~ O.OZ to about 0.3 mil6 ~0.5-7.5 ~icron~). p~eerably about 0.04 to about 0.20 ~il~ -5.~ micron6). Depending on the application, the conductive 6upport may be a ~etal ~late, such a~ aluminum. copper. zinc, 6ilver or the like; a conductive polymeric film; a 6uppor~ such a6 paper, gla6~. synthetic re6in and the like which ha6 .~ been coated with a metal, metal oxide. or ~etal 3s halide by vapor depo6i~ion or chemical depo6ition:
.
-- ~ 3~ 3 ~
a ~uppor~ which has been coated with a conductive ~olymer: or a 6uppor~ which ha~ been Goated wieh a polyme~ic binder con~aining a metal, metal oxide~
~etal halide, conduc~ive polyme~, carbon, or other conductive filler~.
In addi~ion to Gomponen~ deficrib@d abo~e, various ~onven~ional photogLaphi~ ~dditive~, e.g., de~eloping aqent6. ~uper additive~, antifoggant6, ~oating aid6 6uch a6 6~ponin, alkylaryl6ulfonic acid6 lo or ~ul~oalkylæuccinic aeid6; plasticizers 6uch glycerol or l,5-pen~anediol: anti~tatic agent6: agen~
to p~eve~t the Por~ation of s~ot~: antihalation dye6;
underlayer~, ~ubbing or backing laye~; a~d the like ~ay be added ~o the master a~ appropriate. Po6it~ve image6 ~ay be obtained by rever6al proce66ing of the 6ilver halide u6ing either light fogging or a chemical fogging agent: or by u~ing 6ilver halide emul6ion6 that give direct po6itive image6 UBiDg the prefoggi~g technique. Di~ect po~i~ive emul6ion6 have been de6cribed in Leer~maker U.5. Pat. No. 2,184,0l3.
Illing6wor~h U.S. Pat. No. 3,50l,307 and el6ewhere.
Referring now ~o the drawing6. Figure 1 depic~ an elect~ostatic printinq ma~ter in which hoto6en~itive layer l con~ain6 ~en6itized ~ilve~
halide di~per~ed in t~e in~ula~i~g polymeric binder in acco~dance with the invention. Layer 1 i6 generally between 0.5 and 7.5 ~i~ron6 in thickne~, but ~he thickne6~ can be decrea6ed or increa6ed for ~he 6peeific intended application. A thin layer 2 of an adhe6ion promoter ~uch a6 gelatin, which i6 o~ional, aid6 adherence of the phoeo~en~i~ive layer to the ~ondue~ing 6ub~trate 3, whi~h in ~uen i~
mounted on 6uppo~ting 6u~strate ~
The ~a6ter i~ expo6ed imagewi6e u6ing any of the proceduce6 commonly u6ed with ~ilver halide .
~L3~ l37 pho~ographic material6. such a~ by imaging with ac~ini~ light, a cathode ray ~ube, or la~er. ~or - ne~ative-working emul6ion6 ehe latent image 5 i~
then developed by reduc~ng ~he expo6ed ~ilver halide parti~le6 to metallic 6ilver u6ing a con~entional aqueou6 developing solueion. a6 illu6~rated in Figure 2. A conventional aqueou~ fixing solution, such a~ 60dium ~hio6ulfate, i6 ~hen u~ed to remoY~
the unexpo6~d 6ilver halide particles, as illu~trated ~o in ~igure 3. The deYeloped ma6~er i6 then ready for tbe electEo6tati~ printi~g proce66.
Figure 4 illu6trate~ t~e master of Fiqure 3 after it has been cha~ged by a corona discharge ~hat depo~ited po6itive charge6 6 on the ma6ter 6urface.
The area of the film that contain6 ~ilver S pro~ide~
a pathway for overlying charges to pa66 to ground, thus forming a latent image of charges that remain on : the master ~urface. Al~ernatively. charging can be accompli~hed with the u6e of a negative corona di~charge, 6hielded ~orotron~ ~corotron, radioactive 60urce. ~ontact electrode6 ~uch a6 eleet~ically bia6ed 6emiconductive rubber roller~, and ehe like.
The latent i~age i6 ~hen develop~d witb liquid or dry toner 7 of the oppo~ite polariey, a6 :~ 2~ illu6trated ~n Figure 5. Cascade, ma~e~ic bru6h, powder cloud, liquid, r~agne-dry and we~ting develop-ment te~hnique6 are 6uitable. Repre~enta~ive dry ~oner~ that may be u6ed include Kodak Ektaprint K
toner, Hitachi HI-Toner ~MT-414, Cano~ NP-350F ~oner, 30 and To6hiba T-50P toner. Exa~ple& of ~uitable liquid toner6 are Savin 24 toner~ Canon LBP ~one~ and Jame~
River Graphics TlB18 toner. The laten~ image 60 developed ("toned") i6 tran6ferred to the usual ~ub6trate, typically paper. where it i6 fixed in 3S conventional ~a6hion.
.
1'1 Figure6 6 through 9 illu6trate a 8econd embodi~en~ wherQi~ co~ventional diffu6ion ~an6fe technique~ 6u~h a ~ho6e de~cribed in U.S. Patent
2.352.104 and 2.983.606. are uæed to prepare a~
i~aged electro~tatic priAting mas~er of di~persed ~ilve~ in the insulating synthetic bincle~ p~eviou~ly de~cYibed. In thi~ embodimen~, th~ in~ula~i~g 6yntheti~ bi~der 9, approximately 0.25 ~o 3 microns in thick~e~6, eontain~ di6per6e~ developmen~ ~u~ai~
10 a~d a photo6en6itive layer 8 containi~g 6ilver halide ~altg di6peL~ed i~ a hydrophilic colloid ~ha~ o~erlay6 the binder, wherein the ratio of 6il~er to binder 9 ~ 1 to 5:1. A conductive layer 3 and 6ub6trate 4 are employed a6 hereinbefore de6c~ibed. Suitable 15 development nu~lei are well-known in the art, and typically will be (1) a metal, 6uch a6 ~ilver. gold, and ~hodium; (2) 6ulfide6, 6elenide6, telluride6~
poly6ulfide6, or polyselenide6 of metal6 including 6ilver, zinc, chromiu~. gallium, iron, cadmium cobalt, 20 nickel, ~anga~ese, lead, ~ti~ony, bi6~u~h. arsenic, Opp8r, rhodium. palladium, platinum, lanthanum, and ti~aniu~: (3) easily reducible 6il~e~ ~alt6 which f4r~ 6ilver nuclei duLing proce~ g, ~uch as ~ilver nitrate o~ 6ilver cit~ate: (4~ inorganic 6alt6 which 25 ~eac~ with ~he i~coming diffu~ing ~ilver salt~ to form nuclei; and ~5) organic ~ompound6 which (a~
contain a labile 6ulfur atom and ~hich therefore lead ~o the formation of 6ulfide ~uclei during pcoce6~ing, in~luding mercaptans, xanthate~, thioaeetamide.
30 di~hiooxamide, and dithiob~urate or (b~ are reducing agent6 6uch hydrazine derivative~ or 6ilane~ and give ri~e to 6ilver nuclei when evaporated on~o æilicic acid6 or baeium 6ulfate. Likewi6e ~he hydrophilic colloid can be any of the sub~tance~ commonly used in diffu6ion tran6fer proce66e6, 6uch a6 gelatin.
phthala~ed gelatin, cellulo~e deri~fa~iveG ~uch a~
~arboxymethylcellulo~e and hydroxylaethylcellulos0.
and other hydrophilic high molecular weighc colloidal 6ub~ance~ ~uch a6 dextrin, ~oluble 6tar~h. polyvinyl 5 alcohol, or polyfityrene~ulfonic acid.
P~ef~rring ~co Figure 7. photo~en6itive layer ~ i~ imaged in con~rentional fa~hion to form a laten~
image with the ~ensi'cized ~ilver halide. For negative-working e7~ul~ion6 tlle photo6en6i~cive l~yer 10 is then treated with a develoeing agent ~hat redu~eE;
tlle exposed ~ilver halide ~o meealli~ silver, in area 10. and a~ aqueou6 solvent compo~ition ~hat ~onvertF, 6ilver halide in the unexpo~ed area~ to form a 601uble 6ilver halide ~omplex that diffu~e6 into the binder 15 of layer 9 whe~e ie contact~ the development nu~}ei and i6 reduced to insoluble ~ilver particle6 11, forming a silver image. Layer ~ i6 ~hen removed as illustrated in Figure 9. ~e6ulting in an electro-~tatic ma~ter that i~ ready fo~ printin~ in corlven-20 tional manneE. Developing bath6 for the diffu~iontran6er proce6~ are ~ell known in the art and are - de~ibed, for exa~ple, in Diffu~ion Proce66e6 by ~ndre P~ott and E:dith ~eyde (~ocal Pres~, 1972 ) and Modern Pl~ol:o~raPhi~
Proces6ina, trol. 2 by Grant Hai6t ~iley. 1979~.
~ 5any additional embodiment~ will be e~ident to tho~e skilled in the art. For example, a po6itive-working silver halide emul6ion san be u~ed in sonjunc-tion wi~h ~ch~ diffu6ion tran6Per coating 8 illu~trated 30 in Figure6 6 throu~h 9, and 'che expo6ed 6ilver halide ~an be complexed in aqueou~ 601uti on6 to dif fu6e into the ~n6ulating binder layer 9, where it i6 reduced by the development nuclei ~co form the de~ired silver image. Similarly, a 6eparate pho'co~en6itive ~ lm ~an 35 be employed ~ n lieu o coatis~g 8, and brought into operative a660ciation with ~he in~ulating bi~der 9 before or a~ter i~aging~ a6 i~ photo~echanical tran~fer. The photo6en6itive ~ilver halide emul~ion laye~ or coating 8~ and the ln~ula~i~g polyme~i~
binder layer 9 may al60 contain compou~ld6 commonly u6ed in di~fu~ion ~ran~fer ~y~tem6 provided t~at the ~pecific ingredient doe~ ~ot adverEiely a~fec~
in6ula~ing propertie~ of ~he binder or eonduc~iYe propertie~ of ~he 6ilver-containing are!a 11 o the 10 elec~ro~tatic printing ma~ter. Thu~, appropriate an~ifogging agent6. ~uch a6 tetraaza~nclene~ and ; ~ercaptotetrazole6, ~oating aid6. 6uch a6 6aponin and polyalkylene oxides, hardening agent6, ~uch a~
ormaldehyde and chrome alum, and pla6ticizer6 may be lS employed if de6ired. The sub6trate 4 ~180 c~n be tran6parent if the ma~ter i6 to be u6ed a6 a photo-tool or or graphic art~ applications.
Variou6 conventional method6 can be 6elected for toning the electrostatic pr~nting ma~er. If ehe toner particle~ a~e electrically conductive and : ecsentially neutral, or charged oppo~ite of the latent image, they will adhe~e ~o the charged latent imageO I~ the toner i6 ~harged wi~h the 6ame polarity a~ the charged latent image, the ~oner will adhere ~o the uncharged portion. A developme~t electrode can be u~ed to improve the quality of the toned image:
i.e., to facilitate uniform toning of 601id image areafi having latent electro~tatic charge and to pre-vent background ~oning i~ image areas that contain no charge. Tranfifer of the toned image to the de6ired 6ub trate. ~ypically paper. can be as~i~ted by u6ing ; a corona di~charge of oppo6ite polarity o~ the opposite ~ide of the ~ub~traee. Alternatively, toner tran&fer can be accompli6hed with a conduc~ive roller that i8 electrically bia6ed, adhe6ive fil~ and paper.
and the like. ~he toner ~mage ~hu~ ~ran6~erred can be fixed by a teehnigue ~onven~ionally known in the art. V6ually, hea~ing ~ixation, solvent ixat~on.
pre6~ure fixatio~ and the like are e~ployed. If ~e~e~6aly, the 6urface of the ~a~ter may be eleaned by u~i~g a ~leaning ~ean~ ~uch a6 a b~ush, cloth, a blade, a vacuum knife and the like ~o ~e~ove the remaining toner i~age.
Electrostatic printi~g ~a6ter6 offee ~everal advantage~ oYer tho~e described in the prior art.
Since conventional aqueou~ development and fixi~g ~echnique~ !emove byproduc~ ~ha~ are ~oluble in ~he 601ution u~ed for tho~e purpo6e~, the ~a~ter does not ~on~ain byproduct that ~ight interfer with the lS insulating propertie6 of the binder or conductive path of the developed sil~er image, a 6ituation that may be encounte~ed using the dry 6ilver halide ~ developmen~ technique~ de~cribed in U.S. Patent : 4,069,759. Al~o. the in6ulating property of the bi~der6 6~1ected in accordance with the invention i8 le66 sen6i~ive to moi~ture which ca~ in~erfese with the electrosta~ic printin~ proce6~, and ~hu6 the ~a~ter can be u~ed repetitively or after ~torage ~ithout ~he ~eed to heat the ma6ter ~o remove moi~tuLe o~ to unde~Sake 6pe~ial humidity contsol~.
Hiqh re~olutio~ may ~e obtained uBing the elect~o~tatic prin~ing ma~ters provided by the inventlonO aohieving re6ult~ comparable to that ob~ained in high-quality lithogLaphic. flexog~aphic, and letter pre66 prin~ing. ~hile half-tone imaging will ~ormally be ~elec~ed for the6e ~pplication6, it i6 po~ible to ~ailor a ma~e~ for con~inu4u6 tc~e application6 ~ince ~he den6ity of developed ~ilver will ~a!y with intensity of light u6ed to image the film, a6 in ~onventional pho~ography.
~3,,~
1~ , The following example6 ~ur~her illu6~rate variDu6 embodiment6 o the ~nven~io~, and a~e ~ot to be co~6~rued eo limit i~. O~her embodi~ent6 will be apparent ~o those ~killed in the art. In the example~,.all part6 and percentage~ are by veiyht, and all ~empera~ure6 are i~ degree6 Cel6iu~, unle~s otherwi6e ~ated.
Unle66 otherwi~e 6~ated, the ~ilver halide emul6ion6 were negative working and ~en6i~ized with gold and 6ulfur-~ontaining compound~ in a ~o~ventional ~anner~ The ~ilver chloride wa6 doped with 0~13 millimole6 of RhC13 per mole of ~ilver.
P~eParation of Polvmers lS The general pcocedure for the preparation of the polymer6 is illu~trated by the p~epara~ion of Polymer A [~tyrene/methyl methacrylate/ethyl acrylate/
~ethacrylic acid in a 30/10/40/20 weight ratiol a~
given below.
To a five liter fla~k fit~ed wit~ a high 6peed 6tirrer, a reflux co~denser. an additio~ funnel and a thermometer were charged 7aR grams of deioniz~d water, 5 gram6 of Duponol WAQE (60dium lauryl ~ul-fate), 35.2 grams of 6tylene. 11.7 gram~ of methyl methacryla~e, 46.9 grams of ethyl acrylate. 23.4 gram~ o~ ~ethacrylic acid, and 0.5 grams of octyl mercaptan. The flask wa~ purged with nitrogen and ~eated to 60C and held for 15 minute6. Fercou6 ammonium ~ulfa~e, 0.02 grams, ammonium persulfate, 0.2~ gram . and 60dium bi6ulfiSe, 0.28 gram~, were : added to the 1a~k while the mix~ure wa6 emul~ified and maintained at 69-74~C. A ~ixture of 316.5 gram6 of 6tyrene, 105.5 grams of methyl methacrylate, 422 grams of ethyl acrylate, 211 gram6 of metha~rylic acid and S.10 gcam~ of octyl mercaptan wa6 a~ded tc lB
~he flask over a period of 140 ~inute6 while a 601u-~io~ con~aini~g 2.06 gram~ D~ a~monium p~ula~e, 0~52 qIa~6 o 60dium bi6ulfi~e and 19.4 g~am~ of Duponol ~A~E in 1000 gram~ of deionized wa~er was al~o addad over the 140 mlnut~6. Polymerization was continued for an additional hour and the emulsion wa~
allowed to cool 610wly to ambient temperature. A 5%
~alcium ace~a~e ~olu~ion ~a6 added whe~eupon the poly~er coagulated. It wa6 ~trained ro~ exce~6 10 wate~, wa6he~ and fileered repeatedly wi~h deionized wate~ un~il the fil~ra~e became cl~ar, and vacuum dried. Polymer6 B I were prepar~d in a ~i~ilar ~anner. The polyme~ compo6itions and acid number6 are give~ in ~he Table 2 below. The acid numbeI6 ~re defined a~ the milligra~ of pota~6iu~ hydroxide neutralized eer gram of polymer a6 determined ~y ~o~entiometric titr~tion.
_ ~onomer~a ~y~ 5 ~MA EA EMA A~ ~AA ~N
B 25 40 20 ~594 ~ 25 D 30 53 17100 :~ E 25 21 30 24151 a S 2 6tyrene ~MA - me~yl methacrylate EA ~ ethyl acrylate AA ~ acrylic acid MAA ~ ~ethacrylic acid AN - acid number .
. ., l3~
Example~ 1-11 demon6~rate ~he charge retention of the different polyme~ when used with difer~nt 6ilYer halide6 and at different ~ilver halide to polyme~
ratios.
S
Exam~le~ 1-6 A 601ution wa6 made fEom the following ingredient6:
polymera 0.5 gram~
triethylamine 0.3 grams wa~er 3.2 gra~
a Example 1 = Polymee A
~xample 2 = Polymer B
Example 3 = Polymer C
E~ample 4 = Polymer D
Example 5 ~ Polymer E
E~ample 6 = Polymer F
To this solution wa~ added with s~i~ring 12.5 gram~
of a 15.1% ~olu~ion of a silver chloride emul6io~
~AgCl grain~ doped with 0.13 millimoled of ~hC13 per mole of AgCl and w~h a median edge length of 0.13 to 0.17 micron~) containing 3.3 gra~6 of ~ela~in per mole of ~ilver chloride. ~he dispe~ion wa6 coated ~5 onto a co~per-clad polye6ter ba~e by doctor knife.
~he dried films were 2.4 micron~ thick and had 90 milligram6 of silver chloride per 6quare decimet~r, with a ~ilver ion to polymer ratio of 2.8 to 1. The unexposed fiim~ were tray-proce~ed according ~o the following procedure: 1 minute in a commercial litho-graphic de~eloper (CUFD, ~. I. du Pon~ de ~mour6 and Company) at 32.2C, 30 6econd6 in 30~ 60dium thio-~ulfate fixer and 15 6econd~ in 2~ acetic a~id 6tOp both at 25C. followed by cold water wa~hing and drying at 125C for 10 minute6. The proces~ed .3a?6~...3~t7 ~ 1 film6 were mounted on a fla~ plate, ~he copper layer connected to ground. and eguilibrated at 24~C and the qiven relative humidity for one hour. They ~ere then corona ~haLged (with a double wire corotron~ at ~.2 kv. Cha~glng wa6 6topped (at ti~e =Q) and ~he cha~ge allowed ~o de~ay. Electrosta~ic voIeasle~ were de~ee~ined with the u6e of an ele~tro~t:atic 6u~fa~e pro~e. The re6ults~ in voltage6 per mi.cron, are ~ummarized in the Table 3 below.
: ~ABLE 3 --Example ~9~ 1 Z 3 4 5 6 RH=23~
2 55 55 41 6~ 39 63 53 53 39 59 3s 58 ; RH=50%
. 20 2 37 36 30 27 20 44 ~ 60 26 33 23 11 ~2 33 :
Example6 7 10 A solution wa~ made from the following 25 ingredient6:
polymera 32.7 grams trie~hylamine 11.5 grams water 131 grams Example 7 3 Polymec G
30 ~xample ~ . Polymer H
Example 9 ~ Polymer I
~xample 10 - RESYN 28-1300 ~National Sta~ch co~)~
carboxylated poly(vinyl aceta~e) with acid number of 67.
:
fi.
To this solution was added with stirring 74.2 grams of the silver chloride as in Examples 1-6 but containing 33.3 grams of gelatin per mole of silver chloride. The dispersion was coated on copper-clad polyes~er base as in the previous examples. The dried film had a thickness of 4 microns with a silver weight of 80 milligrams per square decimeter. The ratio of silver ion to binder was 1.15 to 1. Films were developed in a commercial X-ray film developer (MXD. E.I. du Pont de Nemours and Company~ and fixer (thiosulfate) at ambient temperature. They were treated with 2% acetic acid, water-rinsed and dried at 125C for 10 minutes. After equilibration at 24C and 37% relatively humidity, the processed films were corona charged as described in the previous examples. The results, in voltages per micron, are summarized in Table 4 below.
EXAMPLE
Time(Sec) 7 8 9 10 Example 11 Example 9 was repeated except that a silver iodobromide emulsion AgBrO 985 lo ol5 with an average grain volume of 0.0185 cubic microns~ containing 13.3 grams of gelatin per mole of silver halide was substituted for the silver chloride. The dry film had a coating thickness of 4 microns and contained 80 milligrams of silver halide per square decimeter. The ratio of silver ion to polymer was l.lS to 1.
The film wa6 p~oce~6ed and charged as in Exameles 7 10. A~ 2~oc and 37~ rel~tive humidi~y, ~he elec~ro6eatic voltage6 held per microm i~ the polymer area~ were ~0, 56, ~7~ and 40 Yolts per 5 mi~ron a~ 2, 30, 600 and 120 6e~0nd~ re6pe~tively.
Exa~ple~ 12-17 demon6~rate the u6e o different conductive 6ub6trate6 with l~wo different insulatiag polymer6.
0 ExamDle 12 Polymer J tmetha~rylamide/~e~hyl ~etha~rylic acid~e~hyl a~rylate/ methacrylic acid in a 4.2~42.8 43/10 ratiol wa~ prepared a6 ~ollow~: a mix~ure o~
4.2 gram6 of ~ethacrylamide. 42.B grams methyl ~ethacrylate, ~3 gram6 ethyl acrylate, 10 ~ra~6 methaccyli~ acid and 0.1 gra~ VA~0 64 initiator ~azobi6i~0butyronlt~ile) in 666 gram6 t-butanol wa6 heated at reflux under a nitrogen atmo6phere for two hour~. A~othe~ 0.1 grams of VAZ0 wa6 added, refluxlng co~ti~ued ~or two hour6, two ~ore addition6 made of 0.1 g~am~ of VAZ0, and ~eflu6i~g continued to a ~otal eeac~io~ ti~e of a hour6. The polym~r wa6 precipi-tated i~ cold ~ater, rin6ed with water. and dried to a white æowder A 601ution wa6 2ade of the following i~gredient6:
Polymer J S.0 gram6 triethylamine 0. 5 gr8m6 water 3~.0 grams To S gram6 of ~he polymer 601ution wa6 added with ~tirring 9.9 gram6 of an ortho-~en6itized ~ilver iodobromide emul~ion a6 i~ Example 11 in whi~h ~e gelatin content wa6 13 grams of gelatin per ~ole of 6ilver halide and the 6ilve~ halide content ~a6 11.~ The di6persion wafi ~oa~ed under red ~afeligh~
2~
condi~ion~ onto aluminum using a wire-wound bar ~o give, af~er drying, a coating of 6.0 ~icron~.
The coa~ing wa~ handled and proce~sed under rad ~afeligh~6. Image6 were prepared by ~ontac~
5 expo~ure ~o hai~one and re601ution targe~s in a vacuu~ fra~e u~ing a ~ung6ten lamp at 56 in~he6 ~la~p output ~ 10 foo~ candl~ lZ inche6 rom the bulb)~
Thi6 exampl2 wa6 expo~ed one ~econd, Sray developed for 1 minute under ni~ogen at~o6phere i6 the 10 following develope~
O.Olt pota66ium b~omide 0.05~ ~odium sul~ite 1.00~ hydroxyla~ine hydrochloride 0.01~ Dimezone-S
1.00% hydroquinone 5.40~ pota66ium carbonate S.40% pota66ium bicarbonate deionized wate~
It wa6 the~ fixed 2 minute6. 6topped 2 minu~es in 2%
20 a~etic acid, rin6ed 2 ~inute~ in distilled water all at 26C, blown dry, and heated 1 ~inutes at 125C.
The lmage con6i6t~ of black 6ilver image vhere the coating wa6 expo6ed and a white background where unexp~6ed. Re~olu~ion wa~ at lea6t 101 line ~5 pai~ per milli~ete~. Charge acceptance and dark d~cay ~ere determined u6ing a ~onloe Model 276A
s~atic charge analyzer. The expo6ed area6 read ini~ial acceptance of R VOltfi which i~ the Eame as an alu~inum blank, and did not decay over 60 second6:
the unexposed area6 initially accepted 153 volt6 which decayed to 100 volt¢ at lD 6econd6, 92 volts at 20 ~econd6, 75 volt6 at ~0 ~econds. Thi~ diffe~ence in charge be~ween the expo~ed and unexpo~ed area~ is u6eful ~o~ electro6tatic ~oning.
rhe elec~eostatic ma~ter wa~ charged with a po6itive corona to ~aximum acceptance char~e while ~he aluminum ~upport wa~ electrically grounded. After a few 6econd6 decay the ground wa6 di~onnected and 5 the plate immersed in a di6per6ion of .nega~i~ely charged black toner particle6 in 1~oea~0, a nonpolar ; hydrocarbon liquid having a Kauri-buta,nol value of about 27, Exxon Core~ Tone~ wa6 at~racted ~o the white non-~ilver part6 of the image making the 10 overall ~a6~er look black. I~ wa6 then rin~ed gently ~n a t~ay of I60par~, drained, ~ewet with I60pa~0.
covered wi~h paper, and passed under the po6i~ive corona to a66i6t toner tran6fer to paper. The image ~ran ferred normally (toner tran6fersed where the 15 master wa6 6ilver-free) and had 6 line pair~millimeter resolution when the ma~ter ~tayed wet with Isopar~
throughout.
Exampl~ 13 The procedure in Example 12 wa6 repeated with the following exceptions: the emul~ion W~6 coated on~o copper-clad Kapton~ (polyimide ~ilm.
E. I. du Pont de Ne~our6 and Company) ~o achieve a thickne~6 of 5.7 micron~:,and the proce6sed film wa6 Z5 heated for 5 minut~6 at 125C. The fini6hed electro-6tatic ma6ter thu6 prepared wa6 mounted on a Savin 770 copier drum and charged and toned, the image transferred to paper a6 in Example 12, to obtain 100-150 copie6 o~ black eoner image with resolution of 20 line pair6 per millimeter.
ExamDle-l4 ; Exa~ple 12 wa~ repeated except tha~ 9.9 gram6 o~ polymer ~olution wa6 u6ed, re6ulting in a ~ilvec ion to polymer ratio of 0.5~ to 1; and the 2s di~persion wa~ coaeed on coppe~-clad ~apton~ with a ~oa~ing thickne66 of 5.7 ~icron6. The ~ub6equent treatment wa6 the ~a~e a6 in Example 13. The ~a6ter appeared to char~e and tone better wit,h ~he higher : 5 petcen~ polymer (Example 1~), but the image coating had a grea~er ee~dency to delaminate.
Example 15 2xample 12 wa~ repeatQd except ~hat the 10 conductive 6ub6trate u6ed wa6 aluminized Mylar~
(polye~ter film, Eo I.-du Pont de Nemour6 and Co~pany~. Thi6 re~ulted in an intact image with no noticeable anchorage or quality problems.
15 Example 16 PDlymer ~ wa6 prepared in the ~ame manner as Polymer J, but u~ing 4.2 gcam6 of methacrylamide.
21.8 gramfi methyl ~ethacryla~e. 64 gram~ ethyl acrylate, and 10 gram6 ~ethacryl~c acid. The film~
20 were prepared, imaged, proceG6ed, ~harged and toned a6 in Example 12. Charge accepta~ce initially was 55 volt~; at 10 ~econd6 i~ wa~ 16 VOl~B.
xa~e 17 , Thi6 example used the 6ame coating and ~ proce~6ing a6 Example 13 except ~hat the image wa6 : heated fo 10 minute~ at 125C. A coating thickne66 of 1.8 ~icron~ wa6 achieved. Image area6 that air dried before heating (A) were 60mewhat cloudy: areas hat were wet when placed in the ove~ (B) were ~ran6-paren~ after heating. The black ~ilver image had re~olution of 228 line pair6 per millimeter. The charge acceptance and decay of the ima~e wa~ deter-~ined on a Monroe 276A Static Charge Analy~er at - ~5 variou6 relative humiditie6 a6 6hown in the Table 5 below. The data are in volt6 per ~icron.
Z~
~l3~
TA~LE 5 ~elative 0 lO 20 30 Humidity ~econd6 6econds6econd6 6econd6 4~ ~ 75 S~ 53 47 20% A ~0 50 43 3 B 4~ 32 27 24 35% ~ 5~ 2~ 23 19 49& A 53 24 1~ 15 63% A 18 5 2 1572~ A 21 - - _ The copper layer of the electrofitatic ma6ter of Example 17 was electcically grounded a~d ~he image po6itively charged with a corona unde~ ambient condi-tion6. Af~er a few second6 the grounded image wa~submerged in a toner bath consi6ting o~ negatively charged toner particle~ opa~, drained. lightly rinsed with I~opar~ and the wat i~a~e tran~fer~ed to aper with the help of a ~egative corona behind the paper. The toner image wa6 positi~e with ~e6pect to the original image, negative with respect to the master, and re601ution wa6 16 line pair6 per ~illi-~eter. The electro6tatic ~aster was recharygd and toned and the ~oner image allowed to dry. Clear ; 30 adhesive tape picked the toner of~ the master to give a clean positive image with re~pect to the original.
with resolution of ~0 line pair6 per milli~eter.
~5 . ~
i~aged electro~tatic priAting mas~er of di~persed ~ilve~ in the insulating synthetic bincle~ p~eviou~ly de~cYibed. In thi~ embodimen~, th~ in~ula~i~g 6yntheti~ bi~der 9, approximately 0.25 ~o 3 microns in thick~e~6, eontain~ di6per6e~ developmen~ ~u~ai~
10 a~d a photo6en6itive layer 8 containi~g 6ilver halide ~altg di6peL~ed i~ a hydrophilic colloid ~ha~ o~erlay6 the binder, wherein the ratio of 6il~er to binder 9 ~ 1 to 5:1. A conductive layer 3 and 6ub6trate 4 are employed a6 hereinbefore de6c~ibed. Suitable 15 development nu~lei are well-known in the art, and typically will be (1) a metal, 6uch a6 ~ilver. gold, and ~hodium; (2) 6ulfide6, 6elenide6, telluride6~
poly6ulfide6, or polyselenide6 of metal6 including 6ilver, zinc, chromiu~. gallium, iron, cadmium cobalt, 20 nickel, ~anga~ese, lead, ~ti~ony, bi6~u~h. arsenic, Opp8r, rhodium. palladium, platinum, lanthanum, and ti~aniu~: (3) easily reducible 6il~e~ ~alt6 which f4r~ 6ilver nuclei duLing proce~ g, ~uch as ~ilver nitrate o~ 6ilver cit~ate: (4~ inorganic 6alt6 which 25 ~eac~ with ~he i~coming diffu~ing ~ilver salt~ to form nuclei; and ~5) organic ~ompound6 which (a~
contain a labile 6ulfur atom and ~hich therefore lead ~o the formation of 6ulfide ~uclei during pcoce6~ing, in~luding mercaptans, xanthate~, thioaeetamide.
30 di~hiooxamide, and dithiob~urate or (b~ are reducing agent6 6uch hydrazine derivative~ or 6ilane~ and give ri~e to 6ilver nuclei when evaporated on~o æilicic acid6 or baeium 6ulfate. Likewi6e ~he hydrophilic colloid can be any of the sub~tance~ commonly used in diffu6ion tran6fer proce66e6, 6uch a6 gelatin.
phthala~ed gelatin, cellulo~e deri~fa~iveG ~uch a~
~arboxymethylcellulo~e and hydroxylaethylcellulos0.
and other hydrophilic high molecular weighc colloidal 6ub~ance~ ~uch a6 dextrin, ~oluble 6tar~h. polyvinyl 5 alcohol, or polyfityrene~ulfonic acid.
P~ef~rring ~co Figure 7. photo~en6itive layer ~ i~ imaged in con~rentional fa~hion to form a laten~
image with the ~ensi'cized ~ilver halide. For negative-working e7~ul~ion6 tlle photo6en6i~cive l~yer 10 is then treated with a develoeing agent ~hat redu~eE;
tlle exposed ~ilver halide ~o meealli~ silver, in area 10. and a~ aqueou6 solvent compo~ition ~hat ~onvertF, 6ilver halide in the unexpo~ed area~ to form a 601uble 6ilver halide ~omplex that diffu~e6 into the binder 15 of layer 9 whe~e ie contact~ the development nu~}ei and i6 reduced to insoluble ~ilver particle6 11, forming a silver image. Layer ~ i6 ~hen removed as illustrated in Figure 9. ~e6ulting in an electro-~tatic ma~ter that i~ ready fo~ printin~ in corlven-20 tional manneE. Developing bath6 for the diffu~iontran6er proce6~ are ~ell known in the art and are - de~ibed, for exa~ple, in Diffu~ion Proce66e6 by ~ndre P~ott and E:dith ~eyde (~ocal Pres~, 1972 ) and Modern Pl~ol:o~raPhi~
Proces6ina, trol. 2 by Grant Hai6t ~iley. 1979~.
~ 5any additional embodiment~ will be e~ident to tho~e skilled in the art. For example, a po6itive-working silver halide emul6ion san be u~ed in sonjunc-tion wi~h ~ch~ diffu6ion tran6Per coating 8 illu~trated 30 in Figure6 6 throu~h 9, and 'che expo6ed 6ilver halide ~an be complexed in aqueou~ 601uti on6 to dif fu6e into the ~n6ulating binder layer 9, where it i6 reduced by the development nuclei ~co form the de~ired silver image. Similarly, a 6eparate pho'co~en6itive ~ lm ~an 35 be employed ~ n lieu o coatis~g 8, and brought into operative a660ciation with ~he in~ulating bi~der 9 before or a~ter i~aging~ a6 i~ photo~echanical tran~fer. The photo6en6itive ~ilver halide emul~ion laye~ or coating 8~ and the ln~ula~i~g polyme~i~
binder layer 9 may al60 contain compou~ld6 commonly u6ed in di~fu~ion ~ran~fer ~y~tem6 provided t~at the ~pecific ingredient doe~ ~ot adverEiely a~fec~
in6ula~ing propertie~ of ~he binder or eonduc~iYe propertie~ of ~he 6ilver-containing are!a 11 o the 10 elec~ro~tatic printing ma~ter. Thu~, appropriate an~ifogging agent6. ~uch a6 tetraaza~nclene~ and ; ~ercaptotetrazole6, ~oating aid6. 6uch a6 6aponin and polyalkylene oxides, hardening agent6, ~uch a~
ormaldehyde and chrome alum, and pla6ticizer6 may be lS employed if de6ired. The sub6trate 4 ~180 c~n be tran6parent if the ma~ter i6 to be u6ed a6 a photo-tool or or graphic art~ applications.
Variou6 conventional method6 can be 6elected for toning the electrostatic pr~nting ma~er. If ehe toner particle~ a~e electrically conductive and : ecsentially neutral, or charged oppo~ite of the latent image, they will adhe~e ~o the charged latent imageO I~ the toner i6 ~harged wi~h the 6ame polarity a~ the charged latent image, the ~oner will adhere ~o the uncharged portion. A developme~t electrode can be u~ed to improve the quality of the toned image:
i.e., to facilitate uniform toning of 601id image areafi having latent electro~tatic charge and to pre-vent background ~oning i~ image areas that contain no charge. Tranfifer of the toned image to the de6ired 6ub trate. ~ypically paper. can be as~i~ted by u6ing ; a corona di~charge of oppo6ite polarity o~ the opposite ~ide of the ~ub~traee. Alternatively, toner tran&fer can be accompli6hed with a conduc~ive roller that i8 electrically bia6ed, adhe6ive fil~ and paper.
and the like. ~he toner ~mage ~hu~ ~ran6~erred can be fixed by a teehnigue ~onven~ionally known in the art. V6ually, hea~ing ~ixation, solvent ixat~on.
pre6~ure fixatio~ and the like are e~ployed. If ~e~e~6aly, the 6urface of the ~a~ter may be eleaned by u~i~g a ~leaning ~ean~ ~uch a6 a b~ush, cloth, a blade, a vacuum knife and the like ~o ~e~ove the remaining toner i~age.
Electrostatic printi~g ~a6ter6 offee ~everal advantage~ oYer tho~e described in the prior art.
Since conventional aqueou~ development and fixi~g ~echnique~ !emove byproduc~ ~ha~ are ~oluble in ~he 601ution u~ed for tho~e purpo6e~, the ~a~ter does not ~on~ain byproduct that ~ight interfer with the lS insulating propertie6 of the binder or conductive path of the developed sil~er image, a 6ituation that may be encounte~ed using the dry 6ilver halide ~ developmen~ technique~ de~cribed in U.S. Patent : 4,069,759. Al~o. the in6ulating property of the bi~der6 6~1ected in accordance with the invention i8 le66 sen6i~ive to moi~ture which ca~ in~erfese with the electrosta~ic printin~ proce6~, and ~hu6 the ~a~ter can be u~ed repetitively or after ~torage ~ithout ~he ~eed to heat the ma6ter ~o remove moi~tuLe o~ to unde~Sake 6pe~ial humidity contsol~.
Hiqh re~olutio~ may ~e obtained uBing the elect~o~tatic prin~ing ma~ters provided by the inventlonO aohieving re6ult~ comparable to that ob~ained in high-quality lithogLaphic. flexog~aphic, and letter pre66 prin~ing. ~hile half-tone imaging will ~ormally be ~elec~ed for the6e ~pplication6, it i6 po~ible to ~ailor a ma~e~ for con~inu4u6 tc~e application6 ~ince ~he den6ity of developed ~ilver will ~a!y with intensity of light u6ed to image the film, a6 in ~onventional pho~ography.
~3,,~
1~ , The following example6 ~ur~her illu6~rate variDu6 embodiment6 o the ~nven~io~, and a~e ~ot to be co~6~rued eo limit i~. O~her embodi~ent6 will be apparent ~o those ~killed in the art. In the example~,.all part6 and percentage~ are by veiyht, and all ~empera~ure6 are i~ degree6 Cel6iu~, unle~s otherwi6e ~ated.
Unle66 otherwi~e 6~ated, the ~ilver halide emul6ion6 were negative working and ~en6i~ized with gold and 6ulfur-~ontaining compound~ in a ~o~ventional ~anner~ The ~ilver chloride wa6 doped with 0~13 millimole6 of RhC13 per mole of ~ilver.
P~eParation of Polvmers lS The general pcocedure for the preparation of the polymer6 is illu~trated by the p~epara~ion of Polymer A [~tyrene/methyl methacrylate/ethyl acrylate/
~ethacrylic acid in a 30/10/40/20 weight ratiol a~
given below.
To a five liter fla~k fit~ed wit~ a high 6peed 6tirrer, a reflux co~denser. an additio~ funnel and a thermometer were charged 7aR grams of deioniz~d water, 5 gram6 of Duponol WAQE (60dium lauryl ~ul-fate), 35.2 grams of 6tylene. 11.7 gram~ of methyl methacryla~e, 46.9 grams of ethyl acrylate. 23.4 gram~ o~ ~ethacrylic acid, and 0.5 grams of octyl mercaptan. The flask wa~ purged with nitrogen and ~eated to 60C and held for 15 minute6. Fercou6 ammonium ~ulfa~e, 0.02 grams, ammonium persulfate, 0.2~ gram . and 60dium bi6ulfiSe, 0.28 gram~, were : added to the 1a~k while the mix~ure wa6 emul~ified and maintained at 69-74~C. A ~ixture of 316.5 gram6 of 6tyrene, 105.5 grams of methyl methacrylate, 422 grams of ethyl acrylate, 211 gram6 of metha~rylic acid and S.10 gcam~ of octyl mercaptan wa6 a~ded tc lB
~he flask over a period of 140 ~inute6 while a 601u-~io~ con~aini~g 2.06 gram~ D~ a~monium p~ula~e, 0~52 qIa~6 o 60dium bi6ulfi~e and 19.4 g~am~ of Duponol ~A~E in 1000 gram~ of deionized wa~er was al~o addad over the 140 mlnut~6. Polymerization was continued for an additional hour and the emulsion wa~
allowed to cool 610wly to ambient temperature. A 5%
~alcium ace~a~e ~olu~ion ~a6 added whe~eupon the poly~er coagulated. It wa6 ~trained ro~ exce~6 10 wate~, wa6he~ and fileered repeatedly wi~h deionized wate~ un~il the fil~ra~e became cl~ar, and vacuum dried. Polymer6 B I were prepar~d in a ~i~ilar ~anner. The polyme~ compo6itions and acid number6 are give~ in ~he Table 2 below. The acid numbeI6 ~re defined a~ the milligra~ of pota~6iu~ hydroxide neutralized eer gram of polymer a6 determined ~y ~o~entiometric titr~tion.
_ ~onomer~a ~y~ 5 ~MA EA EMA A~ ~AA ~N
B 25 40 20 ~594 ~ 25 D 30 53 17100 :~ E 25 21 30 24151 a S 2 6tyrene ~MA - me~yl methacrylate EA ~ ethyl acrylate AA ~ acrylic acid MAA ~ ~ethacrylic acid AN - acid number .
. ., l3~
Example~ 1-11 demon6~rate ~he charge retention of the different polyme~ when used with difer~nt 6ilYer halide6 and at different ~ilver halide to polyme~
ratios.
S
Exam~le~ 1-6 A 601ution wa6 made fEom the following ingredient6:
polymera 0.5 gram~
triethylamine 0.3 grams wa~er 3.2 gra~
a Example 1 = Polymee A
~xample 2 = Polymer B
Example 3 = Polymer C
E~ample 4 = Polymer D
Example 5 ~ Polymer E
E~ample 6 = Polymer F
To this solution wa~ added with s~i~ring 12.5 gram~
of a 15.1% ~olu~ion of a silver chloride emul6io~
~AgCl grain~ doped with 0.13 millimoled of ~hC13 per mole of AgCl and w~h a median edge length of 0.13 to 0.17 micron~) containing 3.3 gra~6 of ~ela~in per mole of ~ilver chloride. ~he dispe~ion wa6 coated ~5 onto a co~per-clad polye6ter ba~e by doctor knife.
~he dried films were 2.4 micron~ thick and had 90 milligram6 of silver chloride per 6quare decimet~r, with a ~ilver ion to polymer ratio of 2.8 to 1. The unexposed fiim~ were tray-proce~ed according ~o the following procedure: 1 minute in a commercial litho-graphic de~eloper (CUFD, ~. I. du Pon~ de ~mour6 and Company) at 32.2C, 30 6econd6 in 30~ 60dium thio-~ulfate fixer and 15 6econd~ in 2~ acetic a~id 6tOp both at 25C. followed by cold water wa~hing and drying at 125C for 10 minute6. The proces~ed .3a?6~...3~t7 ~ 1 film6 were mounted on a fla~ plate, ~he copper layer connected to ground. and eguilibrated at 24~C and the qiven relative humidity for one hour. They ~ere then corona ~haLged (with a double wire corotron~ at ~.2 kv. Cha~glng wa6 6topped (at ti~e =Q) and ~he cha~ge allowed ~o de~ay. Electrosta~ic voIeasle~ were de~ee~ined with the u6e of an ele~tro~t:atic 6u~fa~e pro~e. The re6ults~ in voltage6 per mi.cron, are ~ummarized in the Table 3 below.
: ~ABLE 3 --Example ~9~ 1 Z 3 4 5 6 RH=23~
2 55 55 41 6~ 39 63 53 53 39 59 3s 58 ; RH=50%
. 20 2 37 36 30 27 20 44 ~ 60 26 33 23 11 ~2 33 :
Example6 7 10 A solution wa~ made from the following 25 ingredient6:
polymera 32.7 grams trie~hylamine 11.5 grams water 131 grams Example 7 3 Polymec G
30 ~xample ~ . Polymer H
Example 9 ~ Polymer I
~xample 10 - RESYN 28-1300 ~National Sta~ch co~)~
carboxylated poly(vinyl aceta~e) with acid number of 67.
:
fi.
To this solution was added with stirring 74.2 grams of the silver chloride as in Examples 1-6 but containing 33.3 grams of gelatin per mole of silver chloride. The dispersion was coated on copper-clad polyes~er base as in the previous examples. The dried film had a thickness of 4 microns with a silver weight of 80 milligrams per square decimeter. The ratio of silver ion to binder was 1.15 to 1. Films were developed in a commercial X-ray film developer (MXD. E.I. du Pont de Nemours and Company~ and fixer (thiosulfate) at ambient temperature. They were treated with 2% acetic acid, water-rinsed and dried at 125C for 10 minutes. After equilibration at 24C and 37% relatively humidity, the processed films were corona charged as described in the previous examples. The results, in voltages per micron, are summarized in Table 4 below.
EXAMPLE
Time(Sec) 7 8 9 10 Example 11 Example 9 was repeated except that a silver iodobromide emulsion AgBrO 985 lo ol5 with an average grain volume of 0.0185 cubic microns~ containing 13.3 grams of gelatin per mole of silver halide was substituted for the silver chloride. The dry film had a coating thickness of 4 microns and contained 80 milligrams of silver halide per square decimeter. The ratio of silver ion to polymer was l.lS to 1.
The film wa6 p~oce~6ed and charged as in Exameles 7 10. A~ 2~oc and 37~ rel~tive humidi~y, ~he elec~ro6eatic voltage6 held per microm i~ the polymer area~ were ~0, 56, ~7~ and 40 Yolts per 5 mi~ron a~ 2, 30, 600 and 120 6e~0nd~ re6pe~tively.
Exa~ple~ 12-17 demon6~rate the u6e o different conductive 6ub6trate6 with l~wo different insulatiag polymer6.
0 ExamDle 12 Polymer J tmetha~rylamide/~e~hyl ~etha~rylic acid~e~hyl a~rylate/ methacrylic acid in a 4.2~42.8 43/10 ratiol wa~ prepared a6 ~ollow~: a mix~ure o~
4.2 gram6 of ~ethacrylamide. 42.B grams methyl ~ethacrylate, ~3 gram6 ethyl acrylate, 10 ~ra~6 methaccyli~ acid and 0.1 gra~ VA~0 64 initiator ~azobi6i~0butyronlt~ile) in 666 gram6 t-butanol wa6 heated at reflux under a nitrogen atmo6phere for two hour~. A~othe~ 0.1 grams of VAZ0 wa6 added, refluxlng co~ti~ued ~or two hour6, two ~ore addition6 made of 0.1 g~am~ of VAZ0, and ~eflu6i~g continued to a ~otal eeac~io~ ti~e of a hour6. The polym~r wa6 precipi-tated i~ cold ~ater, rin6ed with water. and dried to a white æowder A 601ution wa6 2ade of the following i~gredient6:
Polymer J S.0 gram6 triethylamine 0. 5 gr8m6 water 3~.0 grams To S gram6 of ~he polymer 601ution wa6 added with ~tirring 9.9 gram6 of an ortho-~en6itized ~ilver iodobromide emul~ion a6 i~ Example 11 in whi~h ~e gelatin content wa6 13 grams of gelatin per ~ole of 6ilver halide and the 6ilve~ halide content ~a6 11.~ The di6persion wafi ~oa~ed under red ~afeligh~
2~
condi~ion~ onto aluminum using a wire-wound bar ~o give, af~er drying, a coating of 6.0 ~icron~.
The coa~ing wa~ handled and proce~sed under rad ~afeligh~6. Image6 were prepared by ~ontac~
5 expo~ure ~o hai~one and re601ution targe~s in a vacuu~ fra~e u~ing a ~ung6ten lamp at 56 in~he6 ~la~p output ~ 10 foo~ candl~ lZ inche6 rom the bulb)~
Thi6 exampl2 wa6 expo~ed one ~econd, Sray developed for 1 minute under ni~ogen at~o6phere i6 the 10 following develope~
O.Olt pota66ium b~omide 0.05~ ~odium sul~ite 1.00~ hydroxyla~ine hydrochloride 0.01~ Dimezone-S
1.00% hydroquinone 5.40~ pota66ium carbonate S.40% pota66ium bicarbonate deionized wate~
It wa6 the~ fixed 2 minute6. 6topped 2 minu~es in 2%
20 a~etic acid, rin6ed 2 ~inute~ in distilled water all at 26C, blown dry, and heated 1 ~inutes at 125C.
The lmage con6i6t~ of black 6ilver image vhere the coating wa6 expo6ed and a white background where unexp~6ed. Re~olu~ion wa~ at lea6t 101 line ~5 pai~ per milli~ete~. Charge acceptance and dark d~cay ~ere determined u6ing a ~onloe Model 276A
s~atic charge analyzer. The expo6ed area6 read ini~ial acceptance of R VOltfi which i~ the Eame as an alu~inum blank, and did not decay over 60 second6:
the unexposed area6 initially accepted 153 volt6 which decayed to 100 volt¢ at lD 6econd6, 92 volts at 20 ~econd6, 75 volt6 at ~0 ~econds. Thi~ diffe~ence in charge be~ween the expo~ed and unexpo~ed area~ is u6eful ~o~ electro6tatic ~oning.
rhe elec~eostatic ma~ter wa~ charged with a po6itive corona to ~aximum acceptance char~e while ~he aluminum ~upport wa~ electrically grounded. After a few 6econd6 decay the ground wa6 di~onnected and 5 the plate immersed in a di6per6ion of .nega~i~ely charged black toner particle6 in 1~oea~0, a nonpolar ; hydrocarbon liquid having a Kauri-buta,nol value of about 27, Exxon Core~ Tone~ wa6 at~racted ~o the white non-~ilver part6 of the image making the 10 overall ~a6~er look black. I~ wa6 then rin~ed gently ~n a t~ay of I60par~, drained, ~ewet with I60pa~0.
covered wi~h paper, and passed under the po6i~ive corona to a66i6t toner tran6fer to paper. The image ~ran ferred normally (toner tran6fersed where the 15 master wa6 6ilver-free) and had 6 line pair~millimeter resolution when the ma~ter ~tayed wet with Isopar~
throughout.
Exampl~ 13 The procedure in Example 12 wa6 repeated with the following exceptions: the emul~ion W~6 coated on~o copper-clad Kapton~ (polyimide ~ilm.
E. I. du Pont de Ne~our6 and Company) ~o achieve a thickne~6 of 5.7 micron~:,and the proce6sed film wa6 Z5 heated for 5 minut~6 at 125C. The fini6hed electro-6tatic ma6ter thu6 prepared wa6 mounted on a Savin 770 copier drum and charged and toned, the image transferred to paper a6 in Example 12, to obtain 100-150 copie6 o~ black eoner image with resolution of 20 line pair6 per millimeter.
ExamDle-l4 ; Exa~ple 12 wa~ repeated except tha~ 9.9 gram6 o~ polymer ~olution wa6 u6ed, re6ulting in a ~ilvec ion to polymer ratio of 0.5~ to 1; and the 2s di~persion wa~ coaeed on coppe~-clad ~apton~ with a ~oa~ing thickne66 of 5.7 ~icron6. The ~ub6equent treatment wa6 the ~a~e a6 in Example 13. The ~a6ter appeared to char~e and tone better wit,h ~he higher : 5 petcen~ polymer (Example 1~), but the image coating had a grea~er ee~dency to delaminate.
Example 15 2xample 12 wa~ repeatQd except ~hat the 10 conductive 6ub6trate u6ed wa6 aluminized Mylar~
(polye~ter film, Eo I.-du Pont de Nemour6 and Co~pany~. Thi6 re~ulted in an intact image with no noticeable anchorage or quality problems.
15 Example 16 PDlymer ~ wa6 prepared in the ~ame manner as Polymer J, but u~ing 4.2 gcam6 of methacrylamide.
21.8 gramfi methyl ~ethacryla~e. 64 gram~ ethyl acrylate, and 10 gram6 ~ethacryl~c acid. The film~
20 were prepared, imaged, proceG6ed, ~harged and toned a6 in Example 12. Charge accepta~ce initially was 55 volt~; at 10 ~econd6 i~ wa~ 16 VOl~B.
xa~e 17 , Thi6 example used the 6ame coating and ~ proce~6ing a6 Example 13 except ~hat the image wa6 : heated fo 10 minute~ at 125C. A coating thickne66 of 1.8 ~icron~ wa6 achieved. Image area6 that air dried before heating (A) were 60mewhat cloudy: areas hat were wet when placed in the ove~ (B) were ~ran6-paren~ after heating. The black ~ilver image had re~olution of 228 line pair6 per millimeter. The charge acceptance and decay of the ima~e wa~ deter-~ined on a Monroe 276A Static Charge Analy~er at - ~5 variou6 relative humiditie6 a6 6hown in the Table 5 below. The data are in volt6 per ~icron.
Z~
~l3~
TA~LE 5 ~elative 0 lO 20 30 Humidity ~econd6 6econds6econd6 6econd6 4~ ~ 75 S~ 53 47 20% A ~0 50 43 3 B 4~ 32 27 24 35% ~ 5~ 2~ 23 19 49& A 53 24 1~ 15 63% A 18 5 2 1572~ A 21 - - _ The copper layer of the electrofitatic ma6ter of Example 17 was electcically grounded a~d ~he image po6itively charged with a corona unde~ ambient condi-tion6. Af~er a few second6 the grounded image wa~submerged in a toner bath consi6ting o~ negatively charged toner particle~ opa~, drained. lightly rinsed with I~opar~ and the wat i~a~e tran~fer~ed to aper with the help of a ~egative corona behind the paper. The toner image wa6 positi~e with ~e6pect to the original image, negative with respect to the master, and re601ution wa6 16 line pair6 per ~illi-~eter. The electro6tatic ~aster was recharygd and toned and the ~oner image allowed to dry. Clear ; 30 adhesive tape picked the toner of~ the master to give a clean positive image with re~pect to the original.
with resolution of ~0 line pair6 per milli~eter.
~5 . ~
3~
ExamPle~ 1~=24 The6e example~ contra6t the propertie6 of film6 fo~med by disper6ing a silver 6alt in gelatin binder6 to those formed by disp~r6ing the 6ame 6ilver alt in the improved in6ula~ion media of ~he pre6~n~
invention. In all ca6e6 ~he 6ilver 6alt u6ed wa~
AgCl g~ain~ doped w;th 0.~3 millimole6 o~ ~hC13 ~e~
~ole of ~gCl with and with a median edge length of 0.13 to 0.17 mieron6. The charge retention wa6 10 mea6ured ater developing the unexeo~ed film~.
. .
(i~ Fil~s with gelatin binder~
~ ~ilve~ chloride di6per~ion wa6 prepared by adding 3610 gram6 of ~ilver chloride curd6 (qrain6 doped with 0.13 millimole6 o~ RhCl3 per mole of AgCl and with a median edge length of 0.13 to 0.17 micron~) ~ontai~ing 13.3 gram6 of gelatin per mole of AgCl ~o ; 3045 gram6 of wa~er, adju6ting the pH to 6.7 with 130 gram6 o 0.1 N sodium hyd~oxide, heating and 6tirring ~ 20 for one hour a~ 45C and adding 214 gram~ of a ~olu-: tion made up by mixing 165.2 g 0.1 N ~odium hyroxide.
32.1 grams tetraazaindene stabilizer~ and 16.7 gra~
water.
tetraazaindene = ~-hydroxy-2-methyl-2~ ~1,2,4~triazolet2,3-b]pyrimidine Gelaein was 6wollen in water at 20C and then dissolved in additiona~. water a~ 50C to give a lS w~% 60lution. 295 grams o the gelatin 601ution was then added to 705 grams of the ~gCl solution to ~ake a net 17.63 wt% AgCl emul6ion. Formaldehyde hardener wa6 added at a concentraeion o 5 gram6 formaldehyde per 1000 gram6 emul6ion. The e~ul~ion wa6 coated onto an indium tin oxide coated polye~te~
6ubstrate (6urface re6i6tivi~y of abou~ 500 oh~ pe~
~3~
square, 5 mil tbick polye~ter ba6e~ u~ing a lab coater. The f ilm6 were tray proce6~ed u6ing standard reagents ln the following ~eguence: develope~. stop, ~ix, stop, Lin~e~ dry. The gelatin6 ul;ed a~d the 5 coating thickne~es after ~roce66ing obta~ned ~e ~ummariz~d in ~able 6.
. (ii) Films with improved polymeric bi~der~
A 601ution wa& made from the following ingredie~t~:
polymer 2.00 gra~
water 10.44 gram6 i~opropanol 3.20 gram6 pota66ium hydroxide0. 30 gram6 pota~sium bicarborlate 0.06 g~a~s acid violet 520 dye0.10 qram6 : To ~his solution was added with ~tirring 54 gram~ o~
AgCl curd~ containing 10 grams gelatin per ~ole of AgCl. The di~per~ion was coa~ed on~o a gel-~ubbed 20 indium tin oxide coated polye6ta~ 6u}~6trate (6urfaçe re6i6tivity of about 500 ohm~ ~er 6quare~ 5 mil thick polye~ter ~ase~ u6ing a wire-wound rod. The ~ilm~
were ~roce~ed following the procedure de6cribed ~o~
the gelatin ~ilms. The polymers u~ed and the coati~g weight obtained are summarized in Table 6.
i5 ;.
3~
COa~Ci ng ThiCkne~6 EXamP1 e ~Bi nde r ~,18 Z68~deiOn1Zed ge1atin 5 . 2 19 26B8deiOniZed ge1atin 1. B
20ROU6~e1Ot ILLS rlOn-deitln1Zed ge1a~in 5.
21RQU6~e10t ILLS non-deionized gelatin 2. 8 22Polymer A 1. 6 23Polymer E o. 9 24Polymer a af~er proces~ing (iii)Determin.a~ion oiE charge retention Sample~ of the above f ilm~ were mounted on 20 an aluminu~ ~late and electrical conneceior~ fcom the conductave ~ndium tin oxide ~ub~tra~e to ground ~a6 made ~ith ~e u6e o~ condu~ive coe~er tape. Th:e lms wer~ eguilibratea in a glove box at a givell relativs humidity a6 mea6ured with an O~ega hand held 25 hygrometer (Model RH-201~ for one hour and then corona cha~ged with a double wice corotron. 5 kV
being applied ~o the corotrsn. Yoltage~ were de~er~isled with the u6e of an electrostaeic 6ucface Yoltage erobe. The re6ult~ are ~ummacized in terms 30 0~ volts per micron i n Table 7 .
, ~ .
TABLE_7 Time ~ec) la 19 20 2122 23 2 T=24C RH=l:Lt ~ 3~ 6113 ~5123 12~ 9g lB 27 3 1591 97 69 Example Ti~e (sec) lB 1920 21 22 23 24 T=23C ~H=30~
lS 1 3 0 0 41 49 27 _ _ Exam~le _ ._ Time (6ec) 18 19 20 2122 23 24 T=22C RH=4BS
Films with gelatin binder6 were heated to determine the effect on the electro6tatic propertle~.
Films in Examples 18-~1 were dried at lOO~C for 10 minutes and then condicioned aC 4B% relati~e humidity for 1 or 10 minutes after which electrostatic data were obtained. These data in volts per ~icron aLe summarized below in Table 8.
, .
.3~7 19 ?_ 2l 1 1~ 1 10 Tame ( ~ec 3 ~in ~in ~in ~in rnin Dlin ~in Dlin 2 2~ 5 ~ 4 6 1 15 3~ 5 ~ 1 1 0 0 1 0 (iv) Toning re~ult6 10~ilm~ rom E~cample6 18-24 were toned with liquid electro6tatic toner containing ~arbon black pigment il~ a ~nodif ied Savin 870 copying machine unde~
identical conditions~ t~le temperature wa6 19C and the relative humidity wa~ 48%. Time from ~orona 15 shargi~g to toning was 15 secon~6 . The double wi re corotron wa~ bia~ed at 6 kV and the development elect~ode wa~ maintained at ground ~otential.
T~an6fer o~ the toller f!om the film ~urface to off6et enainel paper wa~ aecompli6hed with the u6e of a bias 20 tran~fer roll. Once tran6~erred to ~ape~. the toner wa~ thermally fu6ed at 100C in an oven. E~eflection ~` optical den6ity rneafiurernent6 were D~ade with the u~e a Maebe~h RD9~8 den6itometer and are given in the ~' Table 9 below.
:~ 25 Exa~Ple A,mbien~ Heateda 18 0.02 0.56 1~ 0 . ~2 O. 30 ~ 20 0 . 02 0 . ~0 21 0.02 0.27 22 :L. 51 1. 3~
24 1.11 35 aE~eated îor10 minute6 at 100C ~ollowed by 1 mir~ute ~ondi~ioning ~t ambient condition~
' p~ior to toning.
~.~3~it;37 Example~ 26 and 27 illu~trate the u6e of a commer~ial resin as the in~ulating polymeric bi~der.
In 35 grams of water was dis~ol~ed 2.5 y~a~6 of Carbo6~t~ 526 (sopolymer of ethyl acrylate/me~hyl/
metha~yla~e~acrylic a~id in a 17/71/lZ ~atio, ~. F.
Goodrich Co.) and 0.59 grams of triethylamine. Equal a~ou~ts of the ~olymer 601utio~ and ~ilve~ halide emulsion of Example 12 weLe ble~ded and coated at : 60 milligram6 per 6quare ~ecime~e~ on copper clad Kapto~0. Expo6ure and development following the procedu~e in ~xample 12 re~ulted in a black ~ilver image wi~h a clear background with good re601ution.
Charging and charge decay fitudie6 as a function of ~elative humidity were conducted on coating6 o~ pu~e Carbo6et~ 5Z6 at 36.90 milligrams per ~quare deci-meter on copper under the 6ame condition~ a~ Example 17. At 4 to 72t relative humidity Carboset0 526 held charge at least as well o~ better than Polymer J
" of Example 12.
:``
ExamPle-2-6 ample ZS wa~ ~epeated using Carbo~et~ 525 (copolymer of ethyl acrylate~methyl methacrylate/
acrylic acid in a 56/37/7 ratio. B. F. Goodrich, Co.). An image wa6 produced. however it wa~ weaker than tha~ ~f Example 2~.
Example 27 A film wa~ prepared a~ in Example 1 except - ~hat ~he AgCl emulsion contained 13.3 gram6 of gelatin pe~ ~ole of AgCl and the final coa~ing weight was 120 milligrams pe~ ~qua~e decimeter. The film wa~ expo~ed and proce~fied in ~XD (E. ~. du Pont 3~
de Nemour6 and Csmpany. Inc.~ rapid acce~ Xray film developer 60 as to get a variet~ o~ amounts of 6ilver developed. DeYelopment wa6 determined by a Pan~lyzer 4000 (Panametric6, di~i6ion of E6terline Corp.).
S Surface re6i~ance an ~he ~ilver ~maye area6 was mea6ured with a Pluka 77 ~ulti~eter ~John Fluke Mfg.
Co., Inc.) between ~WQ probe6 1 centil~eter apar~.
Acc~pta~ce voltage in the 6ilver i~age acea~ wa~
mea6ured on a Moncoe 276A s~a~ic te6t metec. The re6ul~ are given belQw in Table 10.
TAB~E 10 Acceptance SilverRe6i6tance Voltage oh~6 ~ ~volt~) ~5 : 100 70 4 20 47 __ 88 3~ -- 155 Ex ample 28 Indium tin oxide coated ~ylar~ (polyester film) wa6 coated with a 1.~ milligram per ~quare deci~eter 6ubbing o~ polyvinylidine chlo~ide ~e6in at 200 f~et per minute with a fountain air knife coater.
and heat cet at 170C at 20 pm giving a residence time of 8 ~inute6. Thi~ wa6 ove~coated with a gelatin layec at 0.~ 1.0 milligrams per 6quace decimeter at 200 pm with a ~ountain air knife and heat relaxed at 145C at 4s ~pm gi~ing a ~esidence time o 3.5 minute~.
~3~ 7 A ~olution of Polymer E wa6 prepared by ~dding ~o 231~ gram6 o water with 6t:Lrriag: 454 gram6 i~opropyl alcohol ~95~), 450 gra~ methyl ethyl ketoneO and 13~ gram6 pota~6ium hy~roxide pellet6.
To thi~ ~olu~ion ~a6 added with rapid ~e~rr~ng C00 gram6 of Polymer ~ r$n~ waæ ~ontinued until it : wa6 ~06tly di~olved ~15 minutes). To ~his wa~ added : 54 grams of potassium bicarbonaee. A ~ilver chloride di6per~ion wa6 prepared by addi~g 361~ gra~6 of ~ilver halide curds (g~ain6 doped with 0.13 ~illimole6 of RhC13 per mole of AgC~- and wi~h a median edge l~ngeh of 0.13 to 0.17 mi~ron6) containing 10 gram6 gelatin per mole of ~lver chloride to 2300 gram6 of w~ter and ad~u6ting ~he pH to 6.7 by the addition of 130 gram6 o~ 0.1 N 60dium hydroxide and 15 gram~ of 0.1 N
~ulfuric acid. Thi~ wa~ heated ~or 1 hour at 45C
and ~14 gram6 of a solution made up o~ 386 gra~6 of 0.1 N ~odium hydro~ide, 75 gram6 of tetraazaindene ~tabilizer, and 39 gram6 water was added. Thi6 wa~
20 diluted to ~5~ 6ilver ~hloride with ~14 ~ram6 water.
To 630 gram6 of ~he 25% AgCl ~olu~ion wa~
added ~lowly with 6tirrin~ 247 grams of the polymer ~ ol~tion (15%). Before coating 6.7 gram~ of ~PI-REZ
: 5022 (diglycidyl ether of 1,4-butanediol, Celanese 25 Corp.) wa6 added and coated onto the above treated indium tin oxide ~ylar~ 6heet at 15 ntilligram6 per 6quare decimeter polymer coating weight u6ing a lab coaee~ at 60 f p~t. Thi6 w~t6 dried for 30 6econd~ at 10C, 60 ~econd~ at 30C, and 60 6econd6 a~ 50C.
30 Total dry coating weight was 103 ~illigram6 per 6qtlare decimeter.
Afeer ~xpo6ure and development as in Exam-ple6 18-24 the developed expo~ed 6ilver image had ~urface re6i6tance of 50-100 ohm~ and acceptanee 35 vol~age of i volt a6 mea~ured 2 ~econd~ after 1 R~ 3 7 ~harging. The u~expo~ed non-silver part of the image had an accep~ance voltage of 242 VoltB a8 mea6ur~d 2 second6 ~~er charging. 206 volt6 a~ter 15 second6l and 190 volt~ after ~0 ~econd~ a~ 19%
relative humidity. Toni~g in a modified 5avin 870 Ofice Copier as de~cribed in Example 18-24 ~ave 5-98% dots and 150 lines per ~illime~er re olution.
The i~age ~ran~ferred to paper had a DmaX of 2.4 a ~ in f 0-03 ExamPle ?9 .
I~ thi~ example the inven~ion i6 illu6trated by a diffu~ion tranGfer film. To ~he follo~ing ~olution water 3116 gram~
am~onium hydroxide (29~) B4 gram6 i~opropyl alcohol (9~%) 400 gram~
~ wa6 added with inten~e stir~ing 400 grams of ground : Polymer A. Thi6 ~olueion wa~ left un6tirred until polymer dissolved to~e~nigh~). To 1720 gra~6 of the polymer ~olution wa~ added over 1 minute with rapid etirri~g 600 grams of a 2~ 601ution of zinc 6ul~ate:
then added over 5 ~e~ond~ with ~tirring 210 gram6 of a 1.06Z% ~olution of ~odiu~ 6ulfide: then over 30 6econd6 added 520 grams of z.ss~ 601ution of a~id violet ~20 (antihalation dye). Thi~ wa6 diluted to
ExamPle~ 1~=24 The6e example~ contra6t the propertie6 of film6 fo~med by disper6ing a silver 6alt in gelatin binder6 to those formed by disp~r6ing the 6ame 6ilver alt in the improved in6ula~ion media of ~he pre6~n~
invention. In all ca6e6 ~he 6ilver 6alt u6ed wa~
AgCl g~ain~ doped w;th 0.~3 millimole6 o~ ~hC13 ~e~
~ole of ~gCl with and with a median edge length of 0.13 to 0.17 mieron6. The charge retention wa6 10 mea6ured ater developing the unexeo~ed film~.
. .
(i~ Fil~s with gelatin binder~
~ ~ilve~ chloride di6per~ion wa6 prepared by adding 3610 gram6 of ~ilver chloride curd6 (qrain6 doped with 0.13 millimole6 o~ RhCl3 per mole of AgCl and with a median edge length of 0.13 to 0.17 micron~) ~ontai~ing 13.3 gram6 of gelatin per mole of AgCl ~o ; 3045 gram6 of wa~er, adju6ting the pH to 6.7 with 130 gram6 o 0.1 N sodium hyd~oxide, heating and 6tirring ~ 20 for one hour a~ 45C and adding 214 gram~ of a ~olu-: tion made up by mixing 165.2 g 0.1 N ~odium hyroxide.
32.1 grams tetraazaindene stabilizer~ and 16.7 gra~
water.
tetraazaindene = ~-hydroxy-2-methyl-2~ ~1,2,4~triazolet2,3-b]pyrimidine Gelaein was 6wollen in water at 20C and then dissolved in additiona~. water a~ 50C to give a lS w~% 60lution. 295 grams o the gelatin 601ution was then added to 705 grams of the ~gCl solution to ~ake a net 17.63 wt% AgCl emul6ion. Formaldehyde hardener wa6 added at a concentraeion o 5 gram6 formaldehyde per 1000 gram6 emul6ion. The e~ul~ion wa6 coated onto an indium tin oxide coated polye~te~
6ubstrate (6urface re6i6tivi~y of abou~ 500 oh~ pe~
~3~
square, 5 mil tbick polye~ter ba6e~ u~ing a lab coater. The f ilm6 were tray proce6~ed u6ing standard reagents ln the following ~eguence: develope~. stop, ~ix, stop, Lin~e~ dry. The gelatin6 ul;ed a~d the 5 coating thickne~es after ~roce66ing obta~ned ~e ~ummariz~d in ~able 6.
. (ii) Films with improved polymeric bi~der~
A 601ution wa& made from the following ingredie~t~:
polymer 2.00 gra~
water 10.44 gram6 i~opropanol 3.20 gram6 pota66ium hydroxide0. 30 gram6 pota~sium bicarborlate 0.06 g~a~s acid violet 520 dye0.10 qram6 : To ~his solution was added with ~tirring 54 gram~ o~
AgCl curd~ containing 10 grams gelatin per ~ole of AgCl. The di~per~ion was coa~ed on~o a gel-~ubbed 20 indium tin oxide coated polye6ta~ 6u}~6trate (6urfaçe re6i6tivity of about 500 ohm~ ~er 6quare~ 5 mil thick polye~ter ~ase~ u6ing a wire-wound rod. The ~ilm~
were ~roce~ed following the procedure de6cribed ~o~
the gelatin ~ilms. The polymers u~ed and the coati~g weight obtained are summarized in Table 6.
i5 ;.
3~
COa~Ci ng ThiCkne~6 EXamP1 e ~Bi nde r ~,18 Z68~deiOn1Zed ge1atin 5 . 2 19 26B8deiOniZed ge1atin 1. B
20ROU6~e1Ot ILLS rlOn-deitln1Zed ge1a~in 5.
21RQU6~e10t ILLS non-deionized gelatin 2. 8 22Polymer A 1. 6 23Polymer E o. 9 24Polymer a af~er proces~ing (iii)Determin.a~ion oiE charge retention Sample~ of the above f ilm~ were mounted on 20 an aluminu~ ~late and electrical conneceior~ fcom the conductave ~ndium tin oxide ~ub~tra~e to ground ~a6 made ~ith ~e u6e o~ condu~ive coe~er tape. Th:e lms wer~ eguilibratea in a glove box at a givell relativs humidity a6 mea6ured with an O~ega hand held 25 hygrometer (Model RH-201~ for one hour and then corona cha~ged with a double wice corotron. 5 kV
being applied ~o the corotrsn. Yoltage~ were de~er~isled with the u6e of an electrostaeic 6ucface Yoltage erobe. The re6ult~ are ~ummacized in terms 30 0~ volts per micron i n Table 7 .
, ~ .
TABLE_7 Time ~ec) la 19 20 2122 23 2 T=24C RH=l:Lt ~ 3~ 6113 ~5123 12~ 9g lB 27 3 1591 97 69 Example Ti~e (sec) lB 1920 21 22 23 24 T=23C ~H=30~
lS 1 3 0 0 41 49 27 _ _ Exam~le _ ._ Time (6ec) 18 19 20 2122 23 24 T=22C RH=4BS
Films with gelatin binder6 were heated to determine the effect on the electro6tatic propertle~.
Films in Examples 18-~1 were dried at lOO~C for 10 minutes and then condicioned aC 4B% relati~e humidity for 1 or 10 minutes after which electrostatic data were obtained. These data in volts per ~icron aLe summarized below in Table 8.
, .
.3~7 19 ?_ 2l 1 1~ 1 10 Tame ( ~ec 3 ~in ~in ~in ~in rnin Dlin ~in Dlin 2 2~ 5 ~ 4 6 1 15 3~ 5 ~ 1 1 0 0 1 0 (iv) Toning re~ult6 10~ilm~ rom E~cample6 18-24 were toned with liquid electro6tatic toner containing ~arbon black pigment il~ a ~nodif ied Savin 870 copying machine unde~
identical conditions~ t~le temperature wa6 19C and the relative humidity wa~ 48%. Time from ~orona 15 shargi~g to toning was 15 secon~6 . The double wi re corotron wa~ bia~ed at 6 kV and the development elect~ode wa~ maintained at ground ~otential.
T~an6fer o~ the toller f!om the film ~urface to off6et enainel paper wa~ aecompli6hed with the u6e of a bias 20 tran~fer roll. Once tran6~erred to ~ape~. the toner wa~ thermally fu6ed at 100C in an oven. E~eflection ~` optical den6ity rneafiurernent6 were D~ade with the u~e a Maebe~h RD9~8 den6itometer and are given in the ~' Table 9 below.
:~ 25 Exa~Ple A,mbien~ Heateda 18 0.02 0.56 1~ 0 . ~2 O. 30 ~ 20 0 . 02 0 . ~0 21 0.02 0.27 22 :L. 51 1. 3~
24 1.11 35 aE~eated îor10 minute6 at 100C ~ollowed by 1 mir~ute ~ondi~ioning ~t ambient condition~
' p~ior to toning.
~.~3~it;37 Example~ 26 and 27 illu~trate the u6e of a commer~ial resin as the in~ulating polymeric bi~der.
In 35 grams of water was dis~ol~ed 2.5 y~a~6 of Carbo6~t~ 526 (sopolymer of ethyl acrylate/me~hyl/
metha~yla~e~acrylic a~id in a 17/71/lZ ~atio, ~. F.
Goodrich Co.) and 0.59 grams of triethylamine. Equal a~ou~ts of the ~olymer 601utio~ and ~ilve~ halide emulsion of Example 12 weLe ble~ded and coated at : 60 milligram6 per 6quare ~ecime~e~ on copper clad Kapto~0. Expo6ure and development following the procedu~e in ~xample 12 re~ulted in a black ~ilver image wi~h a clear background with good re601ution.
Charging and charge decay fitudie6 as a function of ~elative humidity were conducted on coating6 o~ pu~e Carbo6et~ 5Z6 at 36.90 milligrams per ~quare deci-meter on copper under the 6ame condition~ a~ Example 17. At 4 to 72t relative humidity Carboset0 526 held charge at least as well o~ better than Polymer J
" of Example 12.
:``
ExamPle-2-6 ample ZS wa~ ~epeated using Carbo~et~ 525 (copolymer of ethyl acrylate~methyl methacrylate/
acrylic acid in a 56/37/7 ratio. B. F. Goodrich, Co.). An image wa6 produced. however it wa~ weaker than tha~ ~f Example 2~.
Example 27 A film wa~ prepared a~ in Example 1 except - ~hat ~he AgCl emulsion contained 13.3 gram6 of gelatin pe~ ~ole of AgCl and the final coa~ing weight was 120 milligrams pe~ ~qua~e decimeter. The film wa~ expo~ed and proce~fied in ~XD (E. ~. du Pont 3~
de Nemour6 and Csmpany. Inc.~ rapid acce~ Xray film developer 60 as to get a variet~ o~ amounts of 6ilver developed. DeYelopment wa6 determined by a Pan~lyzer 4000 (Panametric6, di~i6ion of E6terline Corp.).
S Surface re6i~ance an ~he ~ilver ~maye area6 was mea6ured with a Pluka 77 ~ulti~eter ~John Fluke Mfg.
Co., Inc.) between ~WQ probe6 1 centil~eter apar~.
Acc~pta~ce voltage in the 6ilver i~age acea~ wa~
mea6ured on a Moncoe 276A s~a~ic te6t metec. The re6ul~ are given belQw in Table 10.
TAB~E 10 Acceptance SilverRe6i6tance Voltage oh~6 ~ ~volt~) ~5 : 100 70 4 20 47 __ 88 3~ -- 155 Ex ample 28 Indium tin oxide coated ~ylar~ (polyester film) wa6 coated with a 1.~ milligram per ~quare deci~eter 6ubbing o~ polyvinylidine chlo~ide ~e6in at 200 f~et per minute with a fountain air knife coater.
and heat cet at 170C at 20 pm giving a residence time of 8 ~inute6. Thi~ wa6 ove~coated with a gelatin layec at 0.~ 1.0 milligrams per 6quace decimeter at 200 pm with a ~ountain air knife and heat relaxed at 145C at 4s ~pm gi~ing a ~esidence time o 3.5 minute~.
~3~ 7 A ~olution of Polymer E wa6 prepared by ~dding ~o 231~ gram6 o water with 6t:Lrriag: 454 gram6 i~opropyl alcohol ~95~), 450 gra~ methyl ethyl ketoneO and 13~ gram6 pota~6ium hy~roxide pellet6.
To thi~ ~olu~ion ~a6 added with rapid ~e~rr~ng C00 gram6 of Polymer ~ r$n~ waæ ~ontinued until it : wa6 ~06tly di~olved ~15 minutes). To ~his wa~ added : 54 grams of potassium bicarbonaee. A ~ilver chloride di6per~ion wa6 prepared by addi~g 361~ gra~6 of ~ilver halide curds (g~ain6 doped with 0.13 ~illimole6 of RhC13 per mole of AgC~- and wi~h a median edge l~ngeh of 0.13 to 0.17 mi~ron6) containing 10 gram6 gelatin per mole of ~lver chloride to 2300 gram6 of w~ter and ad~u6ting ~he pH to 6.7 by the addition of 130 gram6 o~ 0.1 N 60dium hydroxide and 15 gram~ of 0.1 N
~ulfuric acid. Thi~ wa~ heated ~or 1 hour at 45C
and ~14 gram6 of a solution made up o~ 386 gra~6 of 0.1 N ~odium hydro~ide, 75 gram6 of tetraazaindene ~tabilizer, and 39 gram6 water was added. Thi6 wa~
20 diluted to ~5~ 6ilver ~hloride with ~14 ~ram6 water.
To 630 gram6 of ~he 25% AgCl ~olu~ion wa~
added ~lowly with 6tirrin~ 247 grams of the polymer ~ ol~tion (15%). Before coating 6.7 gram~ of ~PI-REZ
: 5022 (diglycidyl ether of 1,4-butanediol, Celanese 25 Corp.) wa6 added and coated onto the above treated indium tin oxide ~ylar~ 6heet at 15 ntilligram6 per 6quare decimeter polymer coating weight u6ing a lab coaee~ at 60 f p~t. Thi6 w~t6 dried for 30 6econd~ at 10C, 60 ~econd~ at 30C, and 60 6econd6 a~ 50C.
30 Total dry coating weight was 103 ~illigram6 per 6qtlare decimeter.
Afeer ~xpo6ure and development as in Exam-ple6 18-24 the developed expo~ed 6ilver image had ~urface re6i6tance of 50-100 ohm~ and acceptanee 35 vol~age of i volt a6 mea~ured 2 ~econd~ after 1 R~ 3 7 ~harging. The u~expo~ed non-silver part of the image had an accep~ance voltage of 242 VoltB a8 mea6ur~d 2 second6 ~~er charging. 206 volt6 a~ter 15 second6l and 190 volt~ after ~0 ~econd~ a~ 19%
relative humidity. Toni~g in a modified 5avin 870 Ofice Copier as de~cribed in Example 18-24 ~ave 5-98% dots and 150 lines per ~illime~er re olution.
The i~age ~ran~ferred to paper had a DmaX of 2.4 a ~ in f 0-03 ExamPle ?9 .
I~ thi~ example the inven~ion i6 illu6trated by a diffu~ion tranGfer film. To ~he follo~ing ~olution water 3116 gram~
am~onium hydroxide (29~) B4 gram6 i~opropyl alcohol (9~%) 400 gram~
~ wa6 added with inten~e stir~ing 400 grams of ground : Polymer A. Thi6 ~olueion wa~ left un6tirred until polymer dissolved to~e~nigh~). To 1720 gra~6 of the polymer ~olution wa~ added over 1 minute with rapid etirri~g 600 grams of a 2~ 601ution of zinc 6ul~ate:
then added over 5 ~e~ond~ with ~tirring 210 gram6 of a 1.06Z% ~olution of ~odiu~ 6ulfide: then over 30 6econd6 added 520 grams of z.ss~ 601ution of a~id violet ~20 (antihalation dye). Thi~ wa6 diluted to
4~ by the addition of 1250 gram6 of water~ Before coating, 31 g~am~ of EPI-E~EZ 5022 (diglycidyl ether o~ 1, 4-butan*diol ) wa~ added . Th~ ~olution was coated using a fountain air-knife at ~he following condition6: 200 fpm, 4 inch air knife pre6~ure: onto
5 mil ~hick ~ylar~ (polye~e~) previou61y 6puttered wit~ indium-tin oxide. Thi~ wa6 d~ied a~ 85C. This f ilm was subsequen~cly heat relaxed on a ~epara~e pa s at 145C and 45 fpm giving a ~e6idence time of 3.5 minut*6 a~ 145C. rhis wa~ overco~ted with a blue-6en6itized ~amera ~peed high contrast emul6ion o~
g o.~BrO.195I005 (average grain volume ~ 0.01 cubic micron~ di6per6ed 2:1 in gelatin u6ing a bar coater at 80 ~pm. The inal ~inder layer coating weight wa6 .3 ~illigram6 per ~quare decimeter: ~he emul6ion layer wa~ 73.6 milligram6 per 6quare decimetel. The ratio of 6ilver ion ~o eolymec wa6 3.0 ~o 1. The film wa~ expo6ed and developed with very lietle agitation ~or 1 minute in ~g~a CP297B ~gfa-GaeYert) diffusion t~an6 er developer at 2~C, agitated for 1 ~inute i~ 10~ acetic acid stop 601ution at 28C
re~oving much of the gelatin top layer. rinsed i~
15C wa~e~, and dried at coom tempera~ure.
The unexpo6ed area6 gave developed silver in the ~olymecic binder layer with 6urface resi6tance of 20-35 ohm6 and accep'cance voltage of o YOlt6. The expose~ area~ were 6ilver-free in the eolysQeric bi~der layer and af~er charging. ehe accep~an~e 20 ele~ric ield at 38~ relative humidity was 150 volt6 at 2 second6: 10~ tlolt~ a~c 15 6econds: 91 volts at 30 6econds . Tonislg in a modif ied Savia 870 copying machine a~ de6cribed in Example6 18-24 gaYe 4-98~ halftone dot6/150 line per inch halftone.
The DmaX was 2-5 and the Dmin was ExamPle~ 30~31 ~he~e example~ contra~t the propertie~ of 30 difu6ion tran6fer film~ which contain ei~her gelat;n or a styr~ne-acrylic tetrapolymer a6 the binder ~n ehe receptor layer.
~L3~ 3 7 (i) Diffu~io~ ~ran6fer film with qelatin binder in ~he ~eceptor ~ayer ~Exampl2 30) 60 gram~ of Rou66elo~ Il16 g~lati~ ~ere added to 1360 milliliters o~ deionized wa~er and allowed to 8~iL a~ room temperature with ~a6~ agita-tion ~or 20 minutes. The su~pe~sion wa~ heaeed ~o 52C for 30 ~inute~ and the~ ~ooled ~o 35C. 106 : milliliterg of a 0.15 M zinc sulfate 601ution and
g o.~BrO.195I005 (average grain volume ~ 0.01 cubic micron~ di6per6ed 2:1 in gelatin u6ing a bar coater at 80 ~pm. The inal ~inder layer coating weight wa6 .3 ~illigram6 per ~quare decimeter: ~he emul6ion layer wa~ 73.6 milligram6 per 6quare decimetel. The ratio of 6ilver ion ~o eolymec wa6 3.0 ~o 1. The film wa~ expo6ed and developed with very lietle agitation ~or 1 minute in ~g~a CP297B ~gfa-GaeYert) diffusion t~an6 er developer at 2~C, agitated for 1 ~inute i~ 10~ acetic acid stop 601ution at 28C
re~oving much of the gelatin top layer. rinsed i~
15C wa~e~, and dried at coom tempera~ure.
The unexpo6ed area6 gave developed silver in the ~olymecic binder layer with 6urface resi6tance of 20-35 ohm6 and accep'cance voltage of o YOlt6. The expose~ area~ were 6ilver-free in the eolysQeric bi~der layer and af~er charging. ehe accep~an~e 20 ele~ric ield at 38~ relative humidity was 150 volt6 at 2 second6: 10~ tlolt~ a~c 15 6econds: 91 volts at 30 6econds . Tonislg in a modif ied Savia 870 copying machine a~ de6cribed in Example6 18-24 gaYe 4-98~ halftone dot6/150 line per inch halftone.
The DmaX was 2-5 and the Dmin was ExamPle~ 30~31 ~he~e example~ contra~t the propertie~ of 30 difu6ion tran6fer film~ which contain ei~her gelat;n or a styr~ne-acrylic tetrapolymer a6 the binder ~n ehe receptor layer.
~L3~ 3 7 (i) Diffu~io~ ~ran6fer film with qelatin binder in ~he ~eceptor ~ayer ~Exampl2 30) 60 gram~ of Rou66elo~ Il16 g~lati~ ~ere added to 1360 milliliters o~ deionized wa~er and allowed to 8~iL a~ room temperature with ~a6~ agita-tion ~or 20 minutes. The su~pe~sion wa~ heaeed ~o 52C for 30 ~inute~ and the~ ~ooled ~o 35C. 106 : milliliterg of a 0.15 M zinc sulfate 601ution and
6 ~illilite~s of a 0.15 ~ iron(II) 6ulfa~e ~olution were added o~er a 1 minut~ interval. 336 ~illil~ers of a 0.05 M ~odium ~ulfide eolution wa6 added through a~ orifi~e 60 ~hat the addition ti~e wa6 approximat~ly 2 minute~. The following aqueous solution~ ~ere the~
added:
15% 601ution 0~ Polystep B-27 (S~epan Chemical Co.) 60 ~1 1.33 M formaldehyde 40 ml O.Z64 M chro~ium po~as~ium ulfate 40 ml The ~olution wa~ immediately ~oated onto ~he conduc-~ive ~ide of indium tin oxide ~oated ~ylar~ a~ a coati~g weight between 0.7 and 1.0 gra~6 per ~guare meter of ~ela~in.
ZS An ortho ~en6i~ized camera ~peed high con-trast emul6ion of AgC10 7BrO 3 (average gcai~ volume approximately 0.025 ~ubic micron6) wa6 coated onto ~he gelatin layer at a ~ilver coa~ing weight o~ 3.1 gca~6 per ~guare meter. The emulsion contained no 30 hardener.
The multilayer film wa6 expo6ed i~agewi6e wi~h a ~ung6ten ligh~ and de~eloped in Co~e~ial AgfA PMT developer ~Type CP297B) for 60 second6 at approximately 20C with lit~le agi~ation. The 35 emulsion layer was then removed with pre6~urized 3~
~a3~
water at 38C. The 6ample was wa6hed for 2 ~inutes in 38C water a~d dried at roo~ ee~perature.
(ii) Diffu6io~ ~ran~fer film~ wi~h ~Improved : 5 poly~eri~ binder~ ~Example 31) To a ~olution o~ 4.0 g~am6 o~E Poly~er ~ and 2.5 gram6 of tr1ethyla~i~e in 80 gr~ls o wa~er wa~
added over 1 minute ~ milliliter~ of a 4% aqueous 601utio~ 0~ Zi~ 6ulate. then o~er 5 ~econd~ 19.2 ~illiliter~ o a 0.23% aqueou6 Rolutio~ of sodium ~ulfide. ~fter ~tirri~g 5 ~inute6 the precipi~ate wa~ iltered off and the 601ution containing the zi~c ulide nuclei wa6 coa~ed on the conductive ~ide (surface re~i6tivity ~ 500 ohm6 per ~quare~ o~ indium lS ti~ oxide coated ~ylar~ to give 7 milligramfi per ~qua~e decimeter clean colorles6 polymeric receptor l ayer with 1% zinc 6ulfide nuclei. Thi6 W2~ hea~ed at 125C ~or 10 minute6 to i~prove adhe~ion to the ~onductive ~ub6~rate.
A blue-6en6iti~ed camera-6~eed high con~ra~t conclu~io~ of AgC10 80BrO.l9sIO-0o5 ~g volu~e of 0.01 cubic micron~) di~per6ed 2:1 in gela-tin wa6 coated without hardener over the polymeric receptor layer at ~ ~oating weight of 69 milligram6 2S per 6quare decimeterO
The ~ultilayer coatinq wa~ expo6ed imagewi6e with light and developed in ehe ~o~meLcial ~odak PMT-D
developer (East~an ~odak Co., Chicago. Ill.) ~odified wi~h 12~5~ pota66ium hydrcxide and 5~ pota~iu~
carbGnate for 60 cecond6 at 28C wi~h lietle agita~ion. The developed ima~e wa~ agitat~d 30 6econd~ in 10~ acetic acid 6top ~olution a~ 28~
removing mo~t of the top ~elatin laye~. The black po~itive diffusion tran~fer image in ~he receptor layer remained on the conducting support and wa~
~3~ t7 rin~d ree o gelatin and 1006e 6ilve~ re~idue6 wi~h 40C water, dried. heated 5 minutes at 125C to clean ou~ vola~ile contaminant~. The i~age had D~aX of 3.0-3.5 and low D~in.
The receptor areas co re6~0nding to unexpo6ed image had ~.8 ~alligram6 per zquare deci~eter finely divided black zilver ~etal di.6perzed i~ 6.S milligram6 per ~quare decimeter polymer matrix. The ratio o~
~ilver to polymer of 1.34 to 1 i6 above the thLeshold of about 1.2 and the 6urface re6istance in 6ilver contai~ing area6 wa6 ~ery low. 5 to 14 oh~s. The area~ corte~ponding to the expo6ed image were fairly clean~ nearly colo~le~6 and had 6urface lesiztance of gceate~ than 107 ohm~. The ma~ter wa~ toned on a modified 5avin B70 copying machine as in Examples 18-24. With a 50 volt development electLode po~en-tial the background of the toner image transferred to paper ~orre6pondi~g eo the silver area6 of t~e ma6ter) wa6 completely clean of toner and with halftone dot6 of 2-95~/150 line per inch halftone.
(iii) ~lectroztatic data Data were obtained for the difu6ion transfer 25 film6 in Examples 30-31 at various relative humidites : according to the procedure described for Examples 18-24. The temperature was 22C in all cases. The ~e~ult6 in volt6 per mi~ron are summa~ized in Table 11 .
.~ 3~
3~
_E:xamP l e Time ~sec2 30 31 2 1~ ~5 lG
E~H ~ 30%
2 ~ 34 lS 0 17 RH ~ 49%
2 t~ 2 3 ~: 2~
The diffu~ion t~an~fer Pilm wieh gelatin a6 binder, Example 30, wa6 heated at 100C f or 10 Dlinutes 25 followed by conditioning at ~85i rela~iv~ humidity fo~
1 or 10 ~inutes. The electro~tatic da~a, in ~rolt~
eer micron, obtained immediately af ter ~onditiQning are given in T~ble 12 below.
~ . :
onditioninq Time Time ( sec ) 1 ~in 10 ~in ~ L-~
3~7 ~iv) ~oning re6ult6 Film~ from Example630 31 were toned at 21C and 43t relative hu~idity a6 in Example6 18-24 Reflection optical den6itie~ mea~ured a6 ~n Example~
lB-24 are given in ~he ~able 13 below.
Optical Den~itY _ ~ mbient Hea~eda 0.00 0.73 31 1.~3 Heated at 100C for 10 minute6 followed by conditioning for 1 ~inute at ambient condi~ions.
ExamPle 32 The ~olution of polymer E con~aining ZnS
dev~loement nuclei a6 de~cribed fo~ Example 3~ was coated on gela~in 6ubbed polyefiter ~ilm at 2~ milli-gram6 per square decime~er giving a cl~ar colorle~scsating. ~ piece of Kodak P~T ~egaeive Paper was expo6ed i~agewi6e. The expo~ed PMT paper and receptor polymerJnuclei coating were fed into the.
nip o a la~inator with the eaper emul6ion 6ide facing the nuclei coating and the 6hee~ ~pread apart. ~odak PM~-D developer wa~ applied at the nip between the ~hee~. the 6heet6 were we~ laminated together at 1 meter per minu~e under light nip pre6~ure, the lamina~e wa6 held 30 6econd6 at roo~
ee~perature and then the 6hee~ were 6epar~ted to gîve a black po6i~ive i~age of D ~ax 0.7 and D ~in 0.02 in the receptor coating and a strong negative ~mage on the PM~ paper. ~his illu6tra~e6 ~he well known photomechanical tran6fer proce6s and can be u6ed to prepare a ~ilver i~age in polymer E.
.
added:
15% 601ution 0~ Polystep B-27 (S~epan Chemical Co.) 60 ~1 1.33 M formaldehyde 40 ml O.Z64 M chro~ium po~as~ium ulfate 40 ml The ~olution wa~ immediately ~oated onto ~he conduc-~ive ~ide of indium tin oxide ~oated ~ylar~ a~ a coati~g weight between 0.7 and 1.0 gra~6 per ~guare meter of ~ela~in.
ZS An ortho ~en6i~ized camera ~peed high con-trast emul6ion of AgC10 7BrO 3 (average gcai~ volume approximately 0.025 ~ubic micron6) wa6 coated onto ~he gelatin layer at a ~ilver coa~ing weight o~ 3.1 gca~6 per ~guare meter. The emulsion contained no 30 hardener.
The multilayer film wa6 expo6ed i~agewi6e wi~h a ~ung6ten ligh~ and de~eloped in Co~e~ial AgfA PMT developer ~Type CP297B) for 60 second6 at approximately 20C with lit~le agi~ation. The 35 emulsion layer was then removed with pre6~urized 3~
~a3~
water at 38C. The 6ample was wa6hed for 2 ~inutes in 38C water a~d dried at roo~ ee~perature.
(ii) Diffu6io~ ~ran~fer film~ wi~h ~Improved : 5 poly~eri~ binder~ ~Example 31) To a ~olution o~ 4.0 g~am6 o~E Poly~er ~ and 2.5 gram6 of tr1ethyla~i~e in 80 gr~ls o wa~er wa~
added over 1 minute ~ milliliter~ of a 4% aqueous 601utio~ 0~ Zi~ 6ulate. then o~er 5 ~econd~ 19.2 ~illiliter~ o a 0.23% aqueou6 Rolutio~ of sodium ~ulfide. ~fter ~tirri~g 5 ~inute6 the precipi~ate wa~ iltered off and the 601ution containing the zi~c ulide nuclei wa6 coa~ed on the conductive ~ide (surface re~i6tivity ~ 500 ohm6 per ~quare~ o~ indium lS ti~ oxide coated ~ylar~ to give 7 milligramfi per ~qua~e decimeter clean colorles6 polymeric receptor l ayer with 1% zinc 6ulfide nuclei. Thi6 W2~ hea~ed at 125C ~or 10 minute6 to i~prove adhe~ion to the ~onductive ~ub6~rate.
A blue-6en6iti~ed camera-6~eed high con~ra~t conclu~io~ of AgC10 80BrO.l9sIO-0o5 ~g volu~e of 0.01 cubic micron~) di~per6ed 2:1 in gela-tin wa6 coated without hardener over the polymeric receptor layer at ~ ~oating weight of 69 milligram6 2S per 6quare decimeterO
The ~ultilayer coatinq wa~ expo6ed imagewi6e with light and developed in ehe ~o~meLcial ~odak PMT-D
developer (East~an ~odak Co., Chicago. Ill.) ~odified wi~h 12~5~ pota66ium hydrcxide and 5~ pota~iu~
carbGnate for 60 cecond6 at 28C wi~h lietle agita~ion. The developed ima~e wa~ agitat~d 30 6econd~ in 10~ acetic acid 6top ~olution a~ 28~
removing mo~t of the top ~elatin laye~. The black po~itive diffusion tran~fer image in ~he receptor layer remained on the conducting support and wa~
~3~ t7 rin~d ree o gelatin and 1006e 6ilve~ re~idue6 wi~h 40C water, dried. heated 5 minutes at 125C to clean ou~ vola~ile contaminant~. The i~age had D~aX of 3.0-3.5 and low D~in.
The receptor areas co re6~0nding to unexpo6ed image had ~.8 ~alligram6 per zquare deci~eter finely divided black zilver ~etal di.6perzed i~ 6.S milligram6 per ~quare decimeter polymer matrix. The ratio o~
~ilver to polymer of 1.34 to 1 i6 above the thLeshold of about 1.2 and the 6urface re6istance in 6ilver contai~ing area6 wa6 ~ery low. 5 to 14 oh~s. The area~ corte~ponding to the expo6ed image were fairly clean~ nearly colo~le~6 and had 6urface lesiztance of gceate~ than 107 ohm~. The ma~ter wa~ toned on a modified 5avin B70 copying machine as in Examples 18-24. With a 50 volt development electLode po~en-tial the background of the toner image transferred to paper ~orre6pondi~g eo the silver area6 of t~e ma6ter) wa6 completely clean of toner and with halftone dot6 of 2-95~/150 line per inch halftone.
(iii) ~lectroztatic data Data were obtained for the difu6ion transfer 25 film6 in Examples 30-31 at various relative humidites : according to the procedure described for Examples 18-24. The temperature was 22C in all cases. The ~e~ult6 in volt6 per mi~ron are summa~ized in Table 11 .
.~ 3~
3~
_E:xamP l e Time ~sec2 30 31 2 1~ ~5 lG
E~H ~ 30%
2 ~ 34 lS 0 17 RH ~ 49%
2 t~ 2 3 ~: 2~
The diffu~ion t~an~fer Pilm wieh gelatin a6 binder, Example 30, wa6 heated at 100C f or 10 Dlinutes 25 followed by conditioning at ~85i rela~iv~ humidity fo~
1 or 10 ~inutes. The electro~tatic da~a, in ~rolt~
eer micron, obtained immediately af ter ~onditiQning are given in T~ble 12 below.
~ . :
onditioninq Time Time ( sec ) 1 ~in 10 ~in ~ L-~
3~7 ~iv) ~oning re6ult6 Film~ from Example630 31 were toned at 21C and 43t relative hu~idity a6 in Example6 18-24 Reflection optical den6itie~ mea~ured a6 ~n Example~
lB-24 are given in ~he ~able 13 below.
Optical Den~itY _ ~ mbient Hea~eda 0.00 0.73 31 1.~3 Heated at 100C for 10 minute6 followed by conditioning for 1 ~inute at ambient condi~ions.
ExamPle 32 The ~olution of polymer E con~aining ZnS
dev~loement nuclei a6 de~cribed fo~ Example 3~ was coated on gela~in 6ubbed polyefiter ~ilm at 2~ milli-gram6 per square decime~er giving a cl~ar colorle~scsating. ~ piece of Kodak P~T ~egaeive Paper was expo6ed i~agewi6e. The expo~ed PMT paper and receptor polymerJnuclei coating were fed into the.
nip o a la~inator with the eaper emul6ion 6ide facing the nuclei coating and the 6hee~ ~pread apart. ~odak PM~-D developer wa~ applied at the nip between the ~hee~. the 6heet6 were we~ laminated together at 1 meter per minu~e under light nip pre6~ure, the lamina~e wa6 held 30 6econd6 at roo~
ee~perature and then the 6hee~ were 6epar~ted to gîve a black po6i~ive i~age of D ~ax 0.7 and D ~in 0.02 in the receptor coating and a strong negative ~mage on the PM~ paper. ~his illu6tra~e6 ~he well known photomechanical tran6fer proce6s and can be u6ed to prepare a ~ilver i~age in polymer E.
.
Claims (80)
1. A photosensitive composition suited for aqueous processing consisting essentially of a silver halide photographic salt uniformly dispersed in a synthetic insulating polymeric binder that is swellable in aqueous solutions having a pH higher than approximately 8 1/2, said binder being a copolymer of an unsaturated carboxylic acid monomer and an aromatic monomer and having an insulation value such that it will support an apparent macroscopic electric field of at least approximately five (5) volts/micron as measured 2 seconds following full charging of its surface that has been allowed to equilibrate at 50% relative humidity at 20°C
for 1 hour.
for 1 hour.
2. The composition of claim 1 wherein the binder is swellable in aqueous solutions having a pH in the range of approximately 9 to 14 and has an insulation value of at least approximately 30 volts/micron.
3. The composition of claim 1 wherein the binder has an acid number of approximately 70 to 160.
4. The composition of claim 1 wherein the binder is a copolymer of an aromatic monomer and acrylic or methacrylic acid.
5. The composition of claim 1 having a weight ratio of silver to binder in the range of approximately 0.5 to 3 parts silver per part of binder.
6. The composition of claim 1 wherein said binder is a copolymer containing 10 to 50% by weight a styrene-type monomer, 5 to 50% by weight a carboxylic acid monomer, and 0 to 85% by weight an acrylate-type monomer.
7. The composition of claim 6, wherein said binder is a copolymer containing 25 to 35% by weight a styrene-type monomer, 10 to 25% by weight a carboxylic acid monomer, and 40 to 65% by weight an acrylate-type monomer.
8. The composition of claim 6 wherein the binder is swellable in aqueous solutions having a pH in the range of approximately 9 to 14 and has an insulation value of at least approximately 30 volts/micron.
9. The composition of claim 8 wherein the binder has an acid number of approximately 70 to 160.
10. The composition of claim 9 wherein the binder is a copolymer containing 25 to 35% by weight a styrene-type monomer, 10 to 25% by weight a carboxylic acid monomer, and 40 to 65% by weight an acrylate-type monomer.
11. The composition of claim 10 having a weight ratio of silver ion to binder in the range of approximately 0.5 to 3 parts silver per part of binder.
12. In an electrostatic printer master suited for aqueous processing comprising a conductive substrate that bears a photosensitive coating consisting essentially of silver halide crystals uniformly dispersed in an insulating binder the improvement wherein said binder is a copolymer of an unsaturated carboxylic acid monomer and an aromatic monomer and has ionizing carboxylic acid groups, said copolymer being swellable in aqueous solutions having a pH higher than approximately 8 1/2 and having an insulation value such that it will support an apparent macroscopic electric field of at least approximately five (5) volts/micron as measured 2 seconds following full charging of its surface that has been allowed to equilibrate at 50%
relative humidity at 20°C for 1 hour.
relative humidity at 20°C for 1 hour.
13. The master of claim 12 wherein the binder is swellable in aqueous solutions having a pH in the range of approximately 9 to 14 and has an insulation value of at least approximately 30 volts/micron.
14. The master of claim 12 wherein the binder has an acid number of approximately 70 to 160.
15. The master of claim 12 wherein the binder is a copolymer of an aromatic monomer and acrylic or methacrylic acid.
16. The master of claim 12 wherein the binder has a weight ratio of silver ion to binder in the range of approximately 0.5 to 3 parts silver per part of binder.
17. The master of claim 12 wherein said binder is a copolymer containing 10 to 50% by weight a styrene-type monomer, 5 to 50% by weight a carboxylic acid monomer, and 0 to 85% by weight an acrylate-type monomer.
18. The master of claim 16, wherein said binder is a copolymer containing 25 to 35% by weight a styrene-type monomer, 10 to 25% by weight a carboxylic acid monomer, and 40 to 65% by weight an acrylate-type monomer.
19. The master of claim 17 wherein the binder is swellable in aqueous solutions having a pH in the range of approximately 9 to 14 and has an insulation value of at least approximately 30 volts/micron.
20. The master of claim 19 wherein the binder has an acid number of approximately 70 to 160.
21. The master of claim 20 wherein the binder is a copolymer containing 25 to 35% by weight a styrene-type monomer, 10 to 25% by weight a carboxylic acid monomer, and 40 to 65% by weight an acrylate-type monomer.
22. The master of claim 21 having a weight ratio of silver ion to binder in the range of approximately 0.5 to 3 parts silver per part of binder.
23. In an electrostatic printer master suited for aqueous processing comprising a conductive substrate that bears a photosensitive coating consisting essentially of silver halide crystals uniformly dispersed in an insulating binder, the improvement wherein said binder is a copolymer of an unsaturated carboxylic acid and has an acid number of approximately 70 to 150, said copolymer being swellable in aqueous solutions having a pH higher than approximately 8 1/2 and having an insulation value such that it will support an apparent macroscopic electric field of at least approximately five (5) volts/micron as measured 2 seconds following full charging of its surface that has been allowed to equilibrate at 50% relative humidity at 20°C for 1 hour.
24. The master of claim 23 wherein the binder has carboxylic acid groups and aromatic groups.
25. The master of claim 23 wherein the binder is swellable in aqueous solutions having a pH in the range of approximately 9 to 14 and has an insulation value of at least approximately 30 volts/micron.
26. The master of claim 23 wherein the binder is a copolymer of an aromatic monomer and acrylic or methacrylic acid.
27. The master of claim 23 wherein the binder has a weight ratio of silver ion to binder in the range of approximately 0.5 to 3 parts silver per part of binder.
28. The master of claim 23 wherein said binder is a copolymer containing 10 to 50% by weight a styrene-type monomer, 5 to 50% by weight a carboxylic acid monomer, and 0 to 85% by weight an acrylate-type monomer.
29. The master of claim 28 wherein said binder is a copolymer containing 25 to 35% by weight a styrene-type monomer, 10 to 25% by weight a carboxylic acid monomer, and 40 to 65% by weight an acrylate-type monomer.
30. The master of claim 28 wherein the binder is swellable in aqueous solutions having a pH in the range of approximately 9 to 14 and has an insulation value of at least approximately 30 volts/micron.
31. The master of claim 30 wherein the binder is a copolymer containing 25 to 35% by weight a styrene-type monomer, 10 to 25% by weight a carboxylic acid monomer, and 40 to 65% by weight an acrylate-type monomer.
32. The master of claim 31 having a weight ratio of silver ion to binder in the range of approximately 0.5 to 3 parts silver per part of binder.
33. In a diffusion transfer film comprising development nuclei dispersed in a binder, the improvement wherein said binder is a copolymer of an unsaturated carboxylic acid monomer and an aromatic monomer and has ionizing carboxylic acid groups, said copolymer having an acid number of approximately 70 to 160, being swellable in aqueous solutions having a pH higher than approximately 8 1/2, and having an insulation value such that it will support an apparent macroscopic electric field of at least approximately five (5) volts/micron as measured 2 seconds following full charging of its surface that has been allowed to equilibrate at 50% relative humidity at 20°C for 1 hour.
34. The film of claim 33 wherein the binder is swellable in aqueous solutions having a pH in the range of approximately 9 to 14 and has a insulation value of at least approximately 30 volts/micron.
35. The film of claim 33 wherein the binder is a copolymer of an aromatic monomer and acrylic or methacrylic acid.
36. The film of claim 33 wherein said binder is a copolymer containing 10 to 50% by weight a styrene-type monomer, 5 to 50% by weight a carboxylic acid monomer, and 0 to 85% by weight an acrylate-type monomer.
37. The film of claim 36 wherein said binder is a copolymer containing 25 to 35% by weight a styrene-type monomer, 10 to 25% by weight h carboxylic acid monomer, and 40 to 65% by weight an acrylate-type monomer.
38. The film of claim 36 wherein the binder is swellable in aqueous solutions having a pH in the range of approximately 9 to 14 and has an insulation value of at least approximately 30 volts/micron.
39. The film of claim 38 wherein the binder is a copolymer containing 25 to 35% by weight a styrene-type monomer, 10 to 25% by weight a carboxylic acid monomer, and 40 to 65% by weight an acrylate-type monomer.
40. An electrostatic printer master suited for aqueous silver diffusion transfer processing comprising a conductive substrate that bears a coating consisting essentially of development nuclei dispersed in a binder said binder being a copolymer of an unsaturated carboxylic acid monomer and an aromatic monomer and having ionizing carboxylic acid groups, said copolymer having an acid number of approximately 70 to 160, being swellable in aqueous solutions having a pH higher than approximately 8 1/2, and having an insulation value such that it will support an apparent macroscopic electric field of at least approximately five (5) volts/micro as measured 2 seconds following full charging of its surface that has been allowed to equilibrate at 50% relative humidity at 20°C for 1 hour.
41. The master of claim 40 wherein the binder is swellable in aqueous solutions having a pH in the range of approximately 9 to 14 and has an insulation value of at least approximately 30 volts/micron.
42. The master of claim 40 wherein the binder is a copolymer of an aromatic monomer and acrylic or methacrylic acid.
43. The master of claim 40 wherein said binder is a copolymer containing 10 to 50% by weight a styrene-type monomer, 5 to 50% by weight a carboxylic acid monomer, and 0 to 85% by weight an acrylate-type monomer.
44. The master of claim 43 wherein said binder is a copolymer containing 25 to 35% by weight a styrene type monomer, 10 to 25% by weight a carboxylic acid monomer, and 40 to 65% by weight an acrylate-type monomer.
45. The master of claim 43 wherein the binder is swellable in aqueous solutions having a pH in the range of approximately g to 14 and has an insulation value of at least approximately 30 volts/micron.
46. The master of claim 45 wherein the binder is a copolymer containing 25 to 35% by weight a styrene-type monomer, 10 to 25% by weight a carboxylic acid monomer, and 40 to 65% by weight an acrylate-type monomer.
47. An electrostatic printer master suited for aqueous silver diffusion transfer processing comprising a conductive substrate that bears a coating consisting essentially of development nuclei dispersed in a binder, said binder being a copolymer of an unsaturated carboxylic acid and having an acid number of approximately 70 to 160, said copolymer being swellable in aqueous solutions having a pH higher than approximately 8 1/2 and having an insulation value such that it will support an apparent macroscopic electric field of at least approximately five (5) volts/micron as measured 2 seconds following full charging of its surface that has been allowed to equilibrate at 50% relative humidity at 20°C for 1 hour.
48. The master of claim 47 wherein the binder has carboxylic acid groups and aromatic groups.
49. The master of claim 47 wherein the binder is swellable in aqueous solutions having a pH in the range of approximately 9 to 14 and has an insulation value of at least approximately 30 volts/micron.
50. The master of claim 47 wherein the binder is a copolymer of an aromatic monomer and acrylic or methacrylic acid.
51. The master of claim 47 wherein said binder is a copolymer containing 10 to 50% by weight a styrene-type monomer, 5 to 50% by weight a carboxylic acid monomer, and 0 to 35% by weight an acrylate-type monomer.
52. The master of claim 51 wherein said binder is a copolymer containing 25 to 35% by weight a styrene-type monomer, 10 to 25% by weight a carboxylic acid monomer, and 40 to 65% by weight an acrylate-type monomer.
53. A film consisting essentially of a silver grain image dispersed in a synthetic insulating polymeric binder that is swellable in aqueous solutions having a pH higher than approximately 8 1/2, said binder being a copolymer of an unsaturated carboxylic acid monomer and an aromatic monomer and having ionizing carboxylic acid groups, said composition having an insulation value such that it will support an apparent macroscopic electric field of at least approximately five (5) volts/micron as measured 2 seconds following 50%
relative humidity at 20°C for 1 hour.
relative humidity at 20°C for 1 hour.
54. The film of claim 53 wherein the binder is swellable in aqueous solutions having a pH in the range of approximately 9 to 14 and has an insulation value of at least approximately 30 volts/micron.
55. The film of claim 53 wherein the binder has an acid number of approximately 70 to 160.
56. The film of claim 53 wherein the binder is a copolymer of an aromatic monomer and acrylic or methacrylic acid.
57. The film of claim 53 having a weight ratio of silver ion to binder in the range of approximately 0.5 to 3 parts silver per part of binder.
58. The film of claim 53 wherein said binder is a copolymer containing 10 to 50% by weight a styrene-type monomer, 5 to 50% by weight a carboxylic acid monomer, and 0 to 85% by weight an acrylate-type monomer.
59. The film of claim 58 wherein said binder is a copolymer containing 25 to 35% by weight a styrene-type monomer, 10 to 25% by weight a carboxylic acid monomer, and 40 to 65% by weight an acrylate-type monomer.
60. The film of claim 58 wherein the binder is swellable in aqueous solutions having a pH in the range of approximately g to 14 and has an insulation value of at least approximately 30 volts/micron.
51. The film of claim 60 wherein the binder has an acid number of approximately 70 to 160.
62. The film of claim 61 wherein the binder is a copolymer containing 25 to 35% by weight a styrene-type monomer, 10 to 25% by weight a carboxylic acid monomer, and 40 to 65% by weight an acrylate-type monomer.
63. A conductive substrate that bears a coating consisting essentially of a silver grain image dispersed in a synthetic insulating polymeric binder that is swellable in aqueous solutions having a pH
higher than approximately 8 1/2, said binder being a copolymer of an unsaturated carboxylic acid monomer and an aromatic monomer and having ionizing carboxylic acid groups, said composition having an insulation value such that it will support an apparent macroscopic electric field of at least approximately five (5) volts/micron as measured 2 seconds following full charging of its surface that has been allowed to equilibrate to 50% relative humidity at 20°C for 1 hour.
higher than approximately 8 1/2, said binder being a copolymer of an unsaturated carboxylic acid monomer and an aromatic monomer and having ionizing carboxylic acid groups, said composition having an insulation value such that it will support an apparent macroscopic electric field of at least approximately five (5) volts/micron as measured 2 seconds following full charging of its surface that has been allowed to equilibrate to 50% relative humidity at 20°C for 1 hour.
64. The substrate of claim 63 wherein the binder is swellable in aqueous solutions having a pH in the range of approximately 9 to 14 and has an insulation value of at least approximately 30 volts/micron.
65. The substrate of claim 53 wherein the binder has an acid number of approximately 70 to 160.
66. The substrate of claim 63 wherein the binder is a copolymer of an aromatic monomer and acrylic or methacrylic acid.
67. The substrate of claim 63 having a weight ratio of silver to binder in the range of approximately 0.5 to 3 parts silver per part of binder.
68. The substrate of claim 63 wherein said binder is a copolymer containing 10 to 50% by weight a styrene-type monomer, 5 to 50% by weight a carboxylic acid monomer, and 0 to 85% by weight an acrylate-type monomer.
69. The substrate of claim 68 wherein said binder is a copolymer containing 25 to 35% by weight a styrene-type monomer 10 to 25% by weight a carboxylic acid monomer, and 40 to 65% by weight an acrylate-type monomer.
70. The substrate of claim 68 wherein the binder is swellable in aqueous solutions having a pH in the range of approximately 9 to 14 and has an insulation value of at least approximately 30 volts/micron.
71. The substrate of claim 70 wherein the binder has an acid number of approximately 70 to 160.
72. The substrate of claim 71 wherein the binder is a copolymer containing 25 to 35% by weight a styrene-type monomer, 10 to 25% by weight a carboxylic acid monomer, and 40 to 65% by weight an acrylate-type monomer.
73. A conductive substrate that bears a coating consisting essentially of a silver grain image dispersed in a synthetic insulating polymeric binder that is swellable in aqueous solutions having a pH
higher than approximately 8 1/2, said binder being a copolymer of an unsaturated carboxylic acid monomer and having an acid number of approximately 70 to 160, said composition having an insulation value such that it will support an apparent macroscopic electric field of at least approximately five (5) volts/micron as measured 2 seconds following full charging of its surface that has been allowed to equilibrate to 50%
relative humidity at 20°C for 1 hour.
higher than approximately 8 1/2, said binder being a copolymer of an unsaturated carboxylic acid monomer and having an acid number of approximately 70 to 160, said composition having an insulation value such that it will support an apparent macroscopic electric field of at least approximately five (5) volts/micron as measured 2 seconds following full charging of its surface that has been allowed to equilibrate to 50%
relative humidity at 20°C for 1 hour.
74. The substrate of claim 73 wherein the binder has carboxylic acid groups and aromatic groups.
75. The substrate of claim 73 wherein the binder is swellable in aqueous solutions having a pH in the range of approximately 9 to 14 and has an insulation value of at least approximately 30 volts/micron.
76. The substrate of claim 73 wherein the binder has an acid number of approximately 70 to 160.
77. The substrate of claim 73 wherein the binder is a copolymer of an aromatic monomer and acrylic or methacrylic acid.
78. The substrate of claim 73 having a weight ratio of silver to binder in the range of approximately 0.5 to 3 parts silver par part of binder.
79. The substrate of claim 73 wherein said binder is a copolymer containing 10 to 50% by weight a styrene-type monomer, 5 to 50% by weight a carboxylic acid monomer, and 0. to 85% by weight an acrylate-type monomer.
80. The substrate of claim 79 wherein said binder is a copolymer containing 25 to 35% by weight a styrene-type monomer, 10 to 25% by weight a carboxylic acid monomer, and 40 to 65% by weight an acrylate-type monomer.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US85911486A | 1986-05-02 | 1986-05-02 | |
| US859,114 | 1986-05-02 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1306137C true CA1306137C (en) | 1992-08-11 |
Family
ID=25330072
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000535809A Expired - Lifetime CA1306137C (en) | 1986-05-02 | 1987-04-28 | Silver-based electrostatic printing master |
Country Status (5)
| Country | Link |
|---|---|
| EP (1) | EP0243935B1 (en) |
| JP (1) | JP2683345B2 (en) |
| AU (1) | AU587544B2 (en) |
| CA (1) | CA1306137C (en) |
| DE (1) | DE3750273T2 (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5051329A (en) * | 1989-12-19 | 1991-09-24 | Dximaging | Reversal development of latent electrostatic images on xeroprinting masters |
Family Cites Families (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US1981102A (en) * | 1932-08-10 | 1934-11-20 | Agfa Ansco Corp | Photographic material and process of making the same |
| US2772166A (en) * | 1953-02-11 | 1956-11-27 | Eastman Kodak Co | Hydrophilic compositions and their preparation |
| GB1522642A (en) * | 1974-07-27 | 1978-08-23 | Canon Kk | Master and photosensitive member for use in electrostatic printing |
| GB1574844A (en) * | 1976-01-23 | 1980-09-10 | Canon Kk | Heat-developable photosenstive material |
| JPS5290939A (en) * | 1976-01-26 | 1977-07-30 | Canon Inc | Electrostatic printing |
| US4339505A (en) * | 1980-02-25 | 1982-07-13 | Desoto, Inc. | Electrographic coatings containing acrylamide copolymers |
| JPS5782828A (en) * | 1980-11-11 | 1982-05-24 | Canon Inc | Heat developing photosensitive material |
| JPS5782829A (en) * | 1980-11-11 | 1982-05-24 | Canon Inc | Heat developing photosenstive material |
| JPS6175338A (en) * | 1984-09-21 | 1986-04-17 | Fuji Photo Film Co Ltd | Photosensitive material for silver salt diffusion transfer process |
-
1987
- 1987-04-28 EP EP19870106149 patent/EP0243935B1/en not_active Expired - Lifetime
- 1987-04-28 CA CA000535809A patent/CA1306137C/en not_active Expired - Lifetime
- 1987-04-28 DE DE19873750273 patent/DE3750273T2/en not_active Expired - Fee Related
- 1987-05-01 JP JP62106467A patent/JP2683345B2/en not_active Expired - Fee Related
- 1987-05-01 AU AU72450/87A patent/AU587544B2/en not_active Ceased
Also Published As
| Publication number | Publication date |
|---|---|
| EP0243935A3 (en) | 1990-05-09 |
| DE3750273T2 (en) | 1994-12-15 |
| AU7245087A (en) | 1987-11-05 |
| JP2683345B2 (en) | 1997-11-26 |
| EP0243935A2 (en) | 1987-11-04 |
| AU587544B2 (en) | 1989-08-17 |
| JPS62269135A (en) | 1987-11-21 |
| DE3750273D1 (en) | 1994-09-01 |
| EP0243935B1 (en) | 1994-07-27 |
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