US2940851A

US2940851A - Sensitization of photographic emulsions

Info

Publication number: US2940851A
Application number: US699197A
Authority: US
Inventors: Dorothy J Beavers; Charles V Wilson; James L Graham
Original assignee: Eastman Kodak Co
Current assignee: Eastman Kodak Co
Priority date: 1957-11-27
Filing date: 1957-11-27
Publication date: 1960-06-14
Anticipated expiration: 1977-06-14
Also published as: US2944898A; DE1110521B; GB911501A; US2940855A; DE1110520B; FR1221622A

Description

Patented June 14, 1960 ice 2,940,851 SENSITIZATION OF PHOTOGRAPHIC EMULSIONS Dorothy J. Beavers, Charles V. Wilson, and James L. Graham, Rochester, N.Y., assignors to Eastman Kodak Company, Rochester, N.Y., a corporation of New Jersey No Drawing. Filed Nov. 27, 1957, Ser. No. 699,197

16 Claims. (Cl. 96-66) This invention relates to the sensitization of photographic silver halide emulsions with certain quaternary ammonium salts, e. g., pyridinium and quinolinium salts.

The sensitization of photographic emulsions with compounds containing quaternary nitrogen atoms has been known for many years as shown by the Carroll US. Patent 2,271,623, granted February 3, 1942. A representative quaternary salt sensitizing agent of that patent is the compound ethylene-bis-oxymethylpyridinium perchlorate.

We have discovered certain compounds containing quaternary nitrogen radicals which exhibit improved properties as sensitizing agents for silver halide emulsions, Emulsions containing the compounds of the invention are appreciably more stable than emulsions containing the mentioned quaternary compounds. Accordingly, upon the aging of emulsions containing the new sensitizing agents, less fog is developed and the emulsion speed is maintained. Also, photographic emulsions containing the new quaternary nitrogen compounds maintain their speed over a wider range of development conditions than do emulsions sensitized with previously known alkylenebis-pyridinium salts such as decamethylene-l,10-bispyridinium perchlorate. Thus emulsions containing the latter compound as a sensitizing agent can be expected to lose an appreciable amount of speed when developed with a developing solution of high sulfite content of the order of 100 grams of anhydrous sodium sulfite per liter, whereas the emulsion speed is maintained in such developers when the emulsion is sensitized with the quaternary salts of the present invention.

When the emulsions are sensitized with the quaternary salts of the invention and are used in processes of color photography, that is, in multilayer color films adaptable to the reversal process of color photography, the first development step with the usual Metol-hydroquinone developer produces less fog than when the emulsions are sensitized with other quaternary salts such as that of the above Carroll invention.

It is interesting to note that Howe and Glasset British Patent 566,314 and Vanselow and James PSA Section B, 36-40 (1953), have shown that certain quaternary nitrogen salts such as n-dodecylpyridinium bromide, n-dodecyltriethyl ammonium bromide, etc, are not efiective in increasing speed When development is carried out with a pphenylenediamine as the developing agent such as used in color photography. In fact, it was shown by these workers that development with the p-phenylenediamine developing agent in the presence of the quaternary nitrogen salts retarded the development rate. The quaternary salts of the present invention when employed in the emulsions as sensitizing agents unexpectedly do not retard development when development is carried out with a pphenylenediamine type developing agent.

The quaternary salt sensitizing agents of the invention are bis-quaternary salts having the following general formulas:

I QRCONH(A),, NHCOR'Q' and II QRCONHAQ' where Q and Q represent the same or different organic radicals containing quaternary nitrogen atoms such as trialkyl ammonium salt radicals and cyclammoniumsalt radicals, e.g., pyridinium salt radicals or quinolinium salt radicals, R and R represent the same or different radicals, which may be alkylene, such as (CH and including a carbon chain separated by other atoms such as O or S, 2)n 2)n' or 2)n 2)nb n and n' being integers of from about 1 to 10. The total chain length of R and R must be such that the number of atoms in the linear chain joining Q to Q does not exceed about 30. (The term atoms as used herein refers solely to the actual elements that compose the chain and not to any groups that these elements may carry. For example, --(CH is considered to be a IO-atom chain, the hydrogen atoms being disregarded;

is a 12-atom chain, the oxygen and hydrogen atoms being disregarded.) A compound of the above structure wherein the chain contains 34 atoms has been found not to be useful as a sensitizing agent. Likewise compounds having less than about 14 atoms in the chain are not very useful sensitizing agents, the sensitizing activity of the compounds decreasing rapidly in compounds having less than about 14 or more than about 30 atoms in the linear chain connecting Q to Q. In a preferred embodiment of the invention, therefore, the compounds contain from about 14 to about 30 atoms in the chain.

In Formulas I and II above, group A represents a linear chain of one or more atoms of carbon which may or may not contain sulfur, oxygen or nitrogen as an intermediate linkage. Since n represents the positive integers 1 or 2,

when )1 equals 1, the group A is not present and a group of compounds contemplated by the invention have the formula HI QRCONHNHCOR'Q' IV QRCONHANHCOR'Q In the above formulas the number of atoms comprising A is limited by the number of atoms in R and R. since as mentioned above, the total number of atoms in'the chain connecting Q to Q must not exceed about 30. Thus in Formula IV, A may contain as many as about 24 atoms in a linear chain when R and R are methylene groups. However, in such compounds where A represents an alkylene group, group A can contain only 2 to about 24 carbon atoms in a linear-chain since it has not been possible to synthesize compounds in which A equals a CH:-- group.

oxygen or sulfur wherein =ri and n are positive integers of the order of 1 to 10 selected "so that the linear chain of atoms be:

tween Q and Q contains from about 14 to about 30 'atoms. In the examples hereinafter are provided compounds in which A has been varied as above to obtain very eifective sensitizing agents.

Representative bis-quaternary salts having the above formulas are as follows:

I. 7 4,11-diaza-3,12-dioxotetradecane-Ll4 'bis(pyridinium perchlorate) enema-51 XI. 10,15-diaza 9,16edioxotetracosane 1,24 bis(pyridinium perchlorate) XII. 12,15-diaza-11,16-dioxohexacosane-L26 bis(pyridinium perchlorate) 5 X111. 12,19-diaza-11,20-dioxotriacontane-1,30 bis(pyridinium perchlorate) XIV. 12,19-diaza-l1,20-dioxotriacontane-1,3O bis(isoquinolinium perchlorate) V XV. 12,23-diaza-11,24-dioxotetratriacontane 1,34 bis (pyridinium perchlorate) XVI. 7,13-diaza-6,14-dioxo-10-thianonadecane-1,19 bis (pyridinium perchlorate) I ,7 XVII. 7,10,17,20-tetraza 6;9,'18;2l tetraoxohexacosanei. l;26-bisf( .py'ridinium perchlorate) l5 XVIII. 3-aza-4-oxotetradecane-1,l4 bis(pyridiniumperj chlorate.) ,o V r is V :p-PhenyIene-bisQ-a a-E oxotridecanejpyridinium perchlorate) 7 xx. 7,18-diaza-6,19 dio;rotetracosane 1,24 bis(trimethyl ammonium p toluene sulfona'te) A better understandingoftheiinvention can be obtained by consideration of the structural formulas of a number of the compounds of the invention contemplated by the general formiilas above.

COMPOUND v COMPOUND XVI qomnoonmomnswnnmnootomn if 26104 I o'n, .comron,c orrmomymnooonmnoo onm i 1 COMPOUND XVII vCOMPOUND XIX compound CONH IQNHCO (CH -+NC H 2010 (XV) containing 34 atoms in the linear chain connecting the quaternary nitrogen atoms is ,ph'otographically inert and does not impart any appreciable amount of sensitivity to silver halide emulmom. 7

i The sensitizing eifect of the representative bis-quaternary n'itrogen compound I of the invention having the structure compared with the following bis-quaternary compound Jr .in which the amide linkage is reversed, .is interesting.

In compounds I and Ir the same number of atoms are present inthe chain separating the quaternary nitrogen atoms yet unexpectedly compound I is superior in regard to its sensitizing efiect upon silver halide as shown by the data in Example 7.

I The compounds of the invention having the above general Formulas I, I1, I11 and IV are prepared as indicated in the following flow diagram:

6 w-Bromocaproylchloride, 140 grams (0.66 mole) was dissolved in 500 m1. of dry ether and this solution added through the dropping funnel over a period of one hour, keeping the temperature below A thick slurry formed immediately and was stirred overnight, then alr XRCOOH The above diagram shows that the unsymmetrical diamides can be prepared by reacting the diamine compound consecutively with different w-halo acids, then acid halides. The symmetrical amides are prepared by reacting two moles of the w-halo acid or acid chloride with the desired diamine in a single step followed by the quaternization step. For photographic purposes, the quaternary nitrogen compounds obtained as the halide salts are preferably converted to inert salts such as the perchlorate as illustrated in the syntheses hereafter. In the above flow diagram X represents a halogen atom, e.g., chlorine, bromine or iodine or alkyl or aryl sulfonate ester; R, R, A and n, Q and Q have the significance given above. Representative bis-quaternary salts of this type are synthesized as follows:

COMPOUND VI w-Bromocaproic acid w-Bromocapronitrile, 202 g. (1.15 mole), 350 ml. of 48% hydrobromic acid and 350 ml. of glacial acetic acid were refluxed vigorously for fifteen hours. The product was diluted with 500 m1. of ice water and extracted three times with 500 ml. portions of ether. The solvent was removed on the steam bath and the residue stripped under reduced pressure to remove any acetic acid which may have been extracted along with the product. The 216 g. of crude oil was fractionated under vacuum to yield 181 g. (81.5% yield) of a colorless oil, B.P. 120-140/ 1.2 mm. which solidified to white platelets M.P. 27-29".

To 250 ml. of dry benzene was added 280 g. (1.44 mole) of w-bromocaproic acid. The solution was stirred while 230 g. of oxalyl chloride was added over a period of thirty minutes. A vigorous evolution of hydrogen chloride took place although no temperature rise was evident. The solution was allowed to stand one hour at room temperature, then heated to 60 for two hours. The solvent was removed at 60 under the aspirator. The pale yellow oil weighing 323 g. was fractionated through a 6" Vigreau column. A pale yellow oil with an acid chloride odor weighing 291 g. (95%) was collected at 95102/1 mm.

7,14-diaza-6,1S-dioxoeicosane-LZO-dibromide To a 5 liter flask equipped with stirrer, dropping funnel and condenser was added three liters of dry ether. Thirty-eight grams (0.33 mole) of freshly distilled hexamethylenediamine and 73 grams (0.73 mole) of triethylamine were added to the flaskg'ving a clear solution.

l CsHsN (or tert. amine) lowed to stand for twenty-four hours at room temperature. The thick white slurry was filtered as dry as possible with suction and the remaining traces of ether removed in the vacuum oven at room temperature. The finely divided white powder was vigorously slurried in 2 liters of ice water for fifteen minutes, then filtered. The filter cake was reslurried with ether, filtered, and dried at room temperature in the vacuum oven giving 152 grams (98% yield) of cream-colored solid of M.P. 110.5112. If the melting point of the solid is much lower, the dibromide is dissolved in a minimum of methanol, filtered, ether added to the cloudpoint, and the solution chilled in a Dry Ice acetone bath. With vigorous scratching a crystalline solid of excellent melting point is obtained. The analytical sample was obtained as white needles from acetone and melted at l10-1l2.5.

Analysis.Calc. for C18H34BI'2N202: C, H, N, 6.0; Br, 34.0. Found: C, 45.8; H, 7.0; N, 6.1; Br, 33.7.

7,14-diaza-6,1 5-dioxoeic0sane-1,20-bis(pyridinium perchlorate) One hundred thirty g. of 7,l4-diaza-6,15-dioxoeicosane-1,20-dibromide was added to 700 ml. of pyridine and the mixture heated to reflux for 2 hours. (The solution began precipitating the quaternary salt as an oil after the first 20 minutes of refluxing.) The mixture was cooled, the excess pyridine decanted and the dark orange oil slurried with ether several times, the ether being decanted each time. The syrup Was'dissolved in a small amount of methanol, and dry ether added until no more oil precipitated. The ether was decanted and the trace of solvent removed on the steam bath under vacuum leaving 177 g. of a dark orange oil which contained no pyridine odor.

The oil was dissolved in 500 ml. of methanol in a flask equipped with an efiicient stirrer. A solution of 95.0 g. (0.68 mole) of sodium perchlorate monohydrate in 500 ml. of acetone was added and the thick slurry heated for one-half hour on the steam bath. The sodium bromide which had precipitated was filtered off and the solution concentrated to about 21-300 ml. volume. Acetone, 300 ml., was added and the mixture heated. The sodium bromide which precipitated was filtered off. The solution was chilled in a Dry-Ice acetone bath and with vigorous scratching, dry ether was slowly added to the cloud point. The scratching was continued until a solid precipitate appeared, or if an oil appeared, the excess ether was removed, the solution chilled and the agitatediorJS minutes.

talline 'solid drie'd the vaeuum"'ovena. 'l'lie"dflaromider weighed 285 g. (92%) and had a .M.P. of"'101925-1062'52 Yields :of".'8598 %*of product havebeen. obtained reaction;

melting as low as 50 have proven satisfactory as photographic supersensitizers.

The analytical sample was obtained from methanolether as a white semi-crystalline solid, M.P. 60.5-63.5 Analysis.--Calc. for C I-I Cl N Q C, 50.4; H, 616; N, 8.4; Cl, 10.7. Found: C, 50.3; H,'6;2; N,-8.:5;'Cl,'

COMPOUND X LZO-diaminodecane A twelve liter flask wasequipped with a powerful stirrer, an efficient condenser, and a powder funnel. Eight liters of dry ether were added to the flask and the apparatus swept out with a stream of nitrogen. Granular lithium aluminum hydride, 100 g. (2.6 mole) was added through th'e powder funnel under -a nitrogen atniospherew The funnel was replaced by a dropping-funnel and a solution of '342 g.- (2.6 mole) of anhydrous aluminum chloride in one liter of dry ether was added as rapidly as possible and the resulting slurry stirred 'for 15= minutes.-

A -soldtion 015213 g. (1.3 mole) of sebaconitrile in 250 mll-ofrdry ether wasnow added'through the dropping-funfielrapidly-- enough to cause a noticeable reflux. About one-hour is necessary for the complete addition of the nitrile The grey'mixture was refluxed for two hour's,- then stirred-"at room' temperature overnight.

The lithiumaluminum=hydride-diamine complex wasde'composedby slowlyadding a solution of 250 g. of sodium hydr'oxide in =one-litcr-o water through the dropping funnel while allowing most'of the ether to :escape. Oneppound of sodium chloride was added to -the-resulting grey liquid slutry and the mixture stirred -vigorously with two 2"1.portions of-hot benzene, thebenzene layers: being decanted each time. The benzene was removed r' from .the -extracts gorrtheistearn bath under. vacuum leaving 129 g. of a colorlessoilwhich solidified to a white crystalline mass of decamethylenediamine of M.P. 55 5725 The diarnine shou1d-beprotected from the atmosphereasit readily picks-upcarbon dioxide from' the air forming thedicarbonate salt. 7

The. remaining slurry was extracted continuously with" benzene 'inpa liquid liquid extractor for sixteen hours giving' .an"'additiona1 44.5 gxof diamine possessing a slight yellow color with M.'P:"53'56'. Theoverall yield of' 1;10 diarniuddecanesuitablefor-further reaction is 173.5 g. (78%"); V

7,18-diaza-6,19-dix0tetracosane-1 ,24-dibromide oneyhundred one grams (0.59 mole) ofl,10-diaminodecane was dissolved in 500 ml. of dry benzene. This solutio'rn-was: addedjto a l. flask equipped with an eflicient' stirring motor, a dropping funnel and condenser. Tricthylamine, 130g. (1.29 mole) was added to the solu-, tionzfollowedby the addition of 3 liters of dry etherp A--:solutionaof;250 g. (1.17 mole) of w-bromocaproyl- ChLOfld3:iini-200.m1.;Of dry ether was added to the turbid solution-over :a period of one hour, keeping the tempera-. tureiofrtheaslurry below 25; The thick slurry was stirred atroormtemperature for fourv hours; then allowed to stand iforitwenty four hours. The slurry was filteredas dry rsipossible with suction, washed with ether and. dried. irrithervacuum oven at-roomftemperature. The finely dividedsolid was: added to.2 litersof ice water and rapidly Theslurry was filtered with suction. slurrie'din' ether, filtered againfandthe white 'crys The analytical sample (fronrethanol)"me1ted*at"105?5 Analysis.--Calc. for C H BI N O C, 50.2; H, 7.9; N, 5.3; Br, 30.4. FoundtiC, 5110; 3e.2.-

7,18-diaza-6,19-dioxotetracosane-1524-bis(pyridinium perchlorate) To -a--2 1. flask equippedi withacondenser; was added 285 g. (0.54 mole) of 7,18-diaza 6,19 dioxotetracosane- 1,24-dibromide and 1500 ml. ofdry pyridine. The solution was heated to reflux for'one-and one-half hours,

although the quaternary saltprecipitatedout as an'orange oil after the first fifteen minutes: The mixture. was. chilled, the excess pyridinedecanteiqand.=thegoldensyrup slurried several times with ether, the ether being decanted. The oil was' final1y dissolved in a minimumot methanol, and ether added until no more oil precipitated fromE-thvsohltion; The pi oduct was chilled, the ether decanted, and the remaining traces of solvent removed on the steam bath under vacuum leaving a viscous orange oil.,with no pyridine odor.

The oil was dissolvedjin 500 ml. of methanohand withl eflicient sti'" g a solution of182-g. (1.30 mole;

%" excess) of" sodium. perchlorate monohydrateiin: 1600 ml. of acetone was added. The precipitating sodium.

bromide formed a thick slurry. The mixture was .con-i centrated on the=steam .bath toone-halfth'e original volume and the slurryfiltered with suction. The 'solu-' tion was now concentrated to about 400' ml. andthis sticky residue heated'andslurried with one l. of acetone.

Thesodium bromide which had precipitated was filteredi Twoh'undred'" m1. of methanol was added, andthe solutionchilledin a" oflandthe solution concentrated to V2 1.

Dry. Ice acetone bath. Ether-was slowly added; with vigorous scratching until" the cloud "point' was reached;

or until a solid began precipitating from solution; If

an oil formed first, vigorousscratching of the oil usually resulted in the ,oil solidifying; or ether could be removed, the solution chilled again, and the process repeated. The sticky cream: colored solid.melting at' 63f wasadissolvedin aof '-'methanol, .chilled in. a Dry Ice-)- acetone: bath and "ether? slowly added 'withLscratching; until a' solid beganprecipitatingfrom solution; The

white semi-crystalline solid melted :at. 64-66.5. Another: recrystallization of the 'solid from methanol-ether fimther same manner raised'th'e 'meltingpoint'to 67.'.Q The cream-colored solid weighed 338 g. (86.5%

The analytical sample when recrystallized several-tinies from methanol-ether melted 'at'72.-.75.

Analysis.Calc. for c." H .c1 N-0 0,153.1;11-1; 7.2;-

N, 7.8; C1, 9.8. Found:.C, 529; H, 7.4; N, 7.9; Cl, 9.5.

a I COMPOUND XI 7 p 1 0,15-diaza-9,'16-dibxotetracosane-1,24 dibr0mide Asolution of 30.8 g. (0.19 mole) of 1,4-diaminobutane dihydrochloride in 250 ml. ofwater was added to a1 1. flaskequipped withstirrer and droppingfunnel. A solu-' tionof 38.4 g.-.(0.96 mole.) of sodium hydroxide in 200 mlQof-water-was added and the mixture chilled below 10"; The w-bromopelargonyl chloride (l03 g., 0.38 mole) was..added through the droppingfunnel .at such a rate that. thetemperature of the slurry never rose above 10. After stirring at 010 for two hours, the white solid.

was filtered as dry as possible, then washed withethen The crudewhite solid,'recrystallizedfrom methanolrether,

gave .6715... (67.5 percentlof dibromide .meltingat 11654119".

10,=15 didza-9,16 dioxotetrac0saner1 ,24-bis (pyridinium perchlorate) "-A-" solution -of 6725' 5. (01 129 moldy ot-z 1035M 9 9,16-dioxotetracosane-l,24-dibromide in 275 ml. of dry pyridine was refluxed for two hours. An oil precipitated from solution after the first half hour. The pyridine was removed completely from the product on the steam bath under vacuum. The residue was dissolved in 300 ml. of methanol and added to a solution of 43.0 g. (0.31 mole) of sodium perchlorate monohydrate in 300 ml. of methanol with vigorous stirring. After heating for one hour while concentrating the solution to one-half theoriginal volume, the precipitated sodium bromide was filtered off. This procedure was repeated until sodium bromide no longer precipitated.

The solution was chilled in Dry Ice-acetone and ether slowly added with intense scratching. The solvent was decanted from the sticky solid that separated. This semisolid was dissolved in methanol, chilled in a Dry Ice-acetone bath, and the treatment with ether repeated. A solid melting at 6575 (cloudy) was obtained. Recrystallization of this solid from methanol-ether in the same manner gave 71 g. (72.5 percent) of product melting at 7678 with preliminary softening at 72.

An analytical sample was obtained from methanol upon chilling in a Dry Ice-acetone bath, melting point 80- 825.

Analysis-Cale. for C H N O Cl C, 53.1; H, 7.2; N, 7.8; Cl, 9.8. Found: C, 53.6; H, 7.5; N, 7.8; CI, 9.2.

COMPOUND XVH Ethyl N-w-bromocaproylglycinate A mixture of 19.5 g. (0.10 mole) of w-bromocaproic acid and 12.9 g. (0.10 mole) of carbethoxymethyl isocyanate (mildly exothermic) was heated on the steam bath under anhydrous conditions for six hours. An evolution of carbon dioxide was evident during the reaction. A yellow oil resulted which was dissolved in 50 ml. of dry ether, cooled, and petroleum ether added slowly. A white crystalline solid weighing 18.4 g. (65.7 percent) and melting at 46.548.5 was filtered from the mixture.

The analytical sample of the ester was obtained as matted white needles from ether-petroleum ether, melting point 46.5-48.5

Analysis.Calc. for C H O NBr: C, 42.9; H, 6.4; N, 5.0; Br, 28.6. Found: C, 42.9; H, 6.3; N, 5.2; Br, 28.7.

N-w-bromocaproylglycz'ne N-w-bromocaproylglycine ethyl ester was prepared as above from 52 g. (0.27 mole) of w-bromocaproylglycine and 34.4 g. carbethoxymethyl isocyanate (0.27 mole) and used without further purification for the hydrolysis.

The pale yellow ester was dissolved in 100 ml. methanol and hydrolyzed by slowly adding a solution of 21.2 g. (0.53 mole) sodium hydroxide in 22 ml. of water. The temperature was not allowed to rise above 50 during the addition. After one-half hour, the solution was poured into a large volume of ether, precipitating the sodium salt. The White solid weighed 86 g. (contained some NaOH) and melted cloudy at 174177.

Forty grams of the above salt was dissolved in 20 ml. of water and neutralized to a pH of 3 with 1:1 hydrochloric acid. The mixture was saturated with sodium chloride and then extracted several times with warm benzene and ethyl acetate. The extracts were dried over sodium sulfate, and the solvent removed, leaving 21.0 g. (57 percent) of the substituted glycine as an oil. The acid is extremely ditficult to extract, being only slightly soluble in benzene and ethyl acetate, almost completely insoluble in ether, and fairly soluble in water, even when the aqueous solution has been saturated with sodium chloride.

An analytical sample of the acid was obtained from methanol-petroleum ether and melted at 69.5-70.5

Analysis.Calc. for C H NO Br: C, 38.1; H, 5.6; N, 5.6; Br, 31.8. Found: C, 38.9; H, 5.4; N, 4.7; Br, 30.8. 2

10 7,10,17,20 tetraza 6,9,18,21 tetraox0hexac0sane-I,26

dibromide Seven grams (0.042 mole) of hexamethylene diisocya nate in 50 ml. of dry benzene was added to 21 g. (0.083 mole) of N-w-bromocaproylglycine in ml. dry benzene. The solution was refluxed vigorously. After ten hours, the cream-colored solid that gradually separated in the reaction mixture was collected on a filter and dried; yield, 16.3 g., melting point 160.

The powder was dissolved in 250 ml. of methanol, filtered, and crystallized; melting point -175 softening at 150. A recrystallization from ethanol gave 10.3 g. (41 percent) of white powder of melting point -178 (softens at 160).

Analysis.--Calc. for C H N O Br C, 45.2; H, 6.8; N, 9.6; Br, 27.4. Found: C, 47.6; H, 7.0; N, 10.3; Br, 20.4.

7,10,17,20 tetraza 6,9,18,21 tetraoxohexacosa ne-L26- bis(pyridinium perchlorate) Four grams (0.0069 mole) of the dibromide just above was refluxed vigorously with 25 ml. of pyridine and 25 ml. of ethanol for three hours. The ethanol and pyridine were removed completely on the steam bath under vacuum, leaving a yellow water-soluble gum.

The gum was dissolved in 25 ml. of methanol and a solution of 2.1 g. (0.015 mole) of sodium perchlorate monohydrate in 50 ml. of acetone added. The solution was heated until only 20 ml. of a slurry remained and the precipitated sodium bromide filtered off.

The product was precipitated from ethanol-ether as a sticky white solid when chilled in a Dry Ice-acetone bath. This sticky solid was recrystallized from methanolacetone as a Wax which when triturated with ether turned to 2.0 g. of a white solid of melting point 90100 dec. (38 percent).

Analysis.--Calc. fOl' C3 H5 N5O12Cl2: C, H, N, 10.8; C1, 9.1. Found: C, 47.7; H, 6.4; N, 10.7; C1, 8.1. v

The alternate procedure of preparing quaternary salts of bis-amides from the 0:,w-dih3lld6 (XRCONI-KA) NHCOR'X 7,18 diaza 6,19 dioxotetracosane 1,24 bis(dimethylamine hydrobromide) A mixture of 21.0 g. (0.04 mole) of 7,18-diaza-6,19- dioxotetracosane-1,24-dibromide (prepared as above), 75 ml. of dimethylamine, and 25 0 ml. of ethanol was heated in a .Paar bomb for 16 hours on the steam bath, then allowed to cool slowly to room temperature. The 5 g. of crystalline solid which precipitated was filtered off and identified as starting dibromide.

The orange filtrate was concentrated to about 50 ml. and ether slowly added while chilling in a Dry-Ice-acetone bath. A water-soluble tan solid (15.3 g., 62 percent yield), M.P. l18.5l23.5 was obtained.

A solution of 11.4 g. (0.0185 mole) of 7,18-diaza- 6,19 dioxotetracosane-l,24-bis(dimethylamine hydrobromide), in 50 ml. of water was added to a solution of 7.7 g. (0.056 mole) of potassium carbonate in 50 ml. of water. Chunks of ice were added until no more amine precipitated and the solid was filtered oil, M.P. 108110, wt. 7.0 g. (83.5 percent). The amine was dissolved in acetone, filtered, and the solution chilled in a Dry-Iceacetone bath while slowly adding other. A white crystal- 7 line solid (4 g. 48 percent), M.P. 110111.5 was obtained.

Analysis.Calc. for C H N O C, 68.8; H, 11.9; N, 12.3. Found: C, 68.0; H, 11.5; N, 12.2.

Twenty ml. of ethanol, 2.1 g. (0.011 mole) of methyl p-toluenesulfonateand 2.3 g. (0.005 mole) of the above Weighing ;4;0 g; (98:percentryield) 182-184 C.;

. After. twozrecrystzilliiations from methanoh'ether;

white a crystalline hygroscopic solid was .obtained; 3:8 ge;..M .Rr.188t-190;x. 1 The. analysisrindicates that the salt maylco'ntain; water ofi crystallization; or

solvehtrroficrystalliiatibni 6. 8582] Found z 56Z6;H,:.8Z8; N; 7.5; .S, 8.6;

The-preparation of ta monoamide 1 as indicated in; the flow diagram above is carried out as follows:

3-izzo-4-oxotetradecane-1,14-dibromide Fifteengrams :(0.073 mole) :of 2 hromoethylamine --hydrobromide and- 8.4- g.. (0.21 mole) of sodium hydroxide weredissolved in 75. ml. of'ice water. Keeping the temperature atim j 2058* g." (I073f-mole) Offw-bI'OIIlOUIIdficanoyl chloride gwas slowly i addedthrough azdropping' funnel? After the completefadditionof the chloride; the shin-y was stirred at--' room temperature for 1 /2 hours; then filtered with suctiomi. V V I Anianalvticallypure'product'r(16 g, 59 percent) was obtained by recrystallization from 7 alcohol, M-l.

3j-'aza.-4- oxotetradecane91.1.4-bis(pyridinium perchlorate) T Twentyfiveml';ofifiryspyridinerandfifizg; (0;0 1-3;mole) 053azaa t-oxotetradecanee1,14 dibromide were: heated. at reflux for three hours. The excesspyridine wasremoved and tli 'oilE slurried JseveraL-times with: ether to. remove traces ofipyridine; I

'The residual oil was dissolved in 25 ml. of methanol, andaiafisolution:=ofar4;6 :g; eta-sodium; perchlorate: monohydrate in 25 ml. of acetone: was added-;.' The solution was concentrated-'on-the steam bath-to. one-half the volume and the inorganic salt"fi1tered'ofi." This procedure was carr-ie'd -out until no more sodiunr bromide precipitated upon concentrating the oil. The water-soluble oill would not crystallize afterseveralfattempts; therefore, it .was:isolated=as a pale .ye1lo. w oi1..(4 .g.) r r The other bis quaternary. compounds of 'the invention may be prepared in a similar manner by selection of the appropriate diamine 1 for reaction: with the I appropriate organic acid or organic acid halide.-'

The-following' examples illustrate the use of thebisquaternary salts' of the invention in photographic emulsions? V EXAMPLE-.1,

A high-speed bromoiodide emulsion wasprepared, chemically sensitizedwith sulfur and gold; compounds and-optically sensitized with'a cyanine dye. The amounts of the bisquaternary nitrogen compounds-shown in Table 1 below were added to samples of-theemulsion alone and *together with an azainde'ne stabilizing agent; The emulsionv samples were thencoated; exposed'on. a sensito'meteriand developed-for' S -minutes at 68 F. .inithe developer givenabelow: The speed, gamma and'fogvalues obtained by sensitometric evaluation of the-:developed samples" are also .sh'ownririthe table. The speed .values showntare'expressedat 100"(14-.1og'E') where. E is the exposure in mete'ricandle" seconds required". to produce in tt-he'iemulsion a -density .of: 0z3 above: fog;

'LT B' i Nlimmrear-m speedro 932..."; Gondola-"-1101; 318 1. -0;-16 9304-1-.- LII-DiaZa-E Z-GioXOtetradecaue-l, 4 328; 1. .18-

V bi's(pyridinium perchlorate) (I) 0.75 V g.'/mol/AgX.- 1

3,14-.Diaza'-2 ,--dioxohexadecane-L16 I 328 v 1.

' EXAMPLE 2 L An; emulsion was. provided as in Example 1 and theadditions shown in Table -II Were-made to" samples of the emulsiom Sensitometric evaluationmade-as :deScribed -in Example 1 gavethe resultsshown-in the tablet TABLE:- I1

Number. Feature Speed. Eng

Control; 310 i.11 0. 15 7,14;l)laz a-6,1h-dioxoeicosane-LZO-bis- 334 1. 20 .22 (plyritllmium j'perhlorate)-(v)075. .i .g,mo-... 7,18 Diaza-6;19 di0X0tetfaG0SaJJedfl4 331 1:07

bls(pyridin ium perchlorate) (Y1) 0.75 g./mol.' V 116 4-Hydroxy-6-methyl-1,3,3a,7-tetra 316 1.11 15 zaindene (XXX) 3.0g./mol-. 123-. (XXX) 3 0 g ImOH-( 0 75 g lmol 337 1. 20 .18 124.. (XXX) 3.0 g./m0l+(V) 2.25 g./1110l 343 1. 17 V 19 125.. I (XXX)-3.0 g./mol+(VI)0.75 g./-mol 337 1. 07 21 126 (XX-X-)-3.0'g. /m01+(VI) 2.25'g./m01 346 1.07- .21

7 EXAMPLE 3. An emulsion was provided 'as in 'EXam'plel'l but with: theaddition to 'samples'of the emulsion of'com-pound'sIX and XI, as sh'ownin Tabl'e'III. Processing was'carr'ied out as in"Exa1'n'ple .11 for evaluatir'igthe' emulsion sejnsi? tivity and other characteristics of the emulsion.

TABLE IV Number" Feature Speed 'y Fog- 1977 Control; 308' 1. 0.17 1982 7,14- D.iaza -6;15rdioxoeicosane 1,20-bis 327" 1; 06 .24

r (5-ethyl-2-rnethyl-pyridinium per- 7 chlorate) XVI) 0.75 gJmol. 198341..-. 4,11;Diaza-3;12-dioxotetradecane-l,141 325' 1. 32 21 g g bis(5 ethyl 2 methyL- pyridinium V perchlorate) (II) 0.75 gJIuol. 1985;... 7,10,17,20Tetraza-6,9,18,21-tetraoxo-1, 322 .1. 26' 20 26-bis(pyr1dinium perchlorate) (X-VII)0.75g./mol-. V 2005 4 Hydrow 6 methyl 1,3,3a,7 tetra- 317 1. 35- 14 zamdene (XXX) 3.0 g./mol. (XXX) 8.0'gw/mol-l-(VI) 0.75 gJmoll; 325; 1; 19 3 .19 -(X XX) 3;0 gJmol-i-(VI) 2.25 gJmol... 329 1. 23 21 (XXX) 3; g /m0l+(II)'0.75 g./n.olL. 326 1. 27 .17- (XXX) 3.0 g./mol+(l1) 2.25 g./ni 325 1.21 .19 (XXX) 3.0 g. /m ol+(X'VII) 0.75 g./n1ol 328 1. 35 17 (XXX) 3.0 gJmoH-(XVII) 2L25 gJmoll 329 1. 30' g 18' EXAMPLE 5 A fast bromoiodide emulsion was chemically sensitized with sulfur and gold compounds and optically sensitized with a combination of cyanine dyes. In addition, 3.0 grams per mole of silver halide of 4-hydroxy-6-methyl- 1,3,3a,7-tetrazaindene and 0.75 gram per mole of silver halide of a polyethylene oxide of average molecular weight 1500 were added. The amounts of the alkylene bis-pyridinium salt and compounds X and XI shown in 14 fixation, silver bleaching and final fixation. Color Process 1 was carried out at 75 F. as follows: (1) Negative development-l minutes (2) Reversal flash exposure (3) Color development-15 minutes (4) Silver bleaching-8 minutes Fixing-3 minutes The negative developer had the following composition:

10 c 0 1i rs... 1.0 Table V were then added and the emulsions coated. Test- 90 F (32 C te in was carried out as EX 1 1 th fr m SOdll-llll hexametaphosphate grams 2.0 g m amp 6 upon es N-methyl p-aminophenol sulfate ..do.. 6.0 coated emulsion samples and other samples of each emul- Sodium sulfite desiccated do 50 0 o men were incubated for 1 week at 120 F. and 50 per- Hydmquinone 64) cent relative humidity. Still other samples of each Sodium carbonate, monohydrated 3 5 0 emulsion were stored under room conditions 78 F. potassium bromide 29 K p ug and evel ped with the same developing solusodium thigcyanate 5 1111 S 0 111 ample 1 with the result shown In Table 0.5% solution (6-nitrobenzimidazole nitrate) -cc 12.0 V. Consideration of the Fog data in the table shows 0.1% solution of potassium iodide cc 10.0

TABLE V Fresh Tests llniubfztggr 3 Moths,ig8 F.,

, w e Number Feature ep g P- '7 F g Sp. 7 Fog Sp. 7 Fog 7s Control 3 1.12 0.15 343 1. 01 0.16 337 1. 05 0.16 7820 Hexladelcamgthylene-l,16-b1s(pyrld1niu1n perchlorate) 0.15 356 1.10 .24 359 1.10 .22 353 1. .20

g. mo g 7821 liexladefaingtihyleue-l,16-bis(pyrldinium perchlorate) 0.3 356 1.24 .30 359 1.02 .34 359 1.23 .26

g. mo g 7822 Hexladefaingghylene-l,16-bls(pyridlnium perchlorate) 0.6 355 1.17 .29 345 .90 .48 356 1.23 .31

g. m0 g 7826 7,IB-Dlaza-G,19-dioxotetracosane-1,24bis-(pyridinlum per- 352 1.09 .19 364 1.01 .19 351 1.27 .19

chlorate) (X) 0.45 g./mol AgX. 7827 7,18-Dlaza-6,19'dioxotet'racosa11e-1,24-b1s-(pyndm1um per- 358 1.14 .20 362 1.20 .20 353 1.32 .19

chlorate) (X) 0.75 g./mol AgX. 7828 7,18-Diaza-6,19-dioxotetracosane-1,24-b1s-(pyrldlnlum per- 357 1.33 .23 362 1.18 .22 354 1.25 .20

chlorate) (X) 1.2 g./mol AgX. v 7839 10,15-Diaza-9,l6-dioxotetracosane-1,24-b1s-(pyridnnum per- 352 1.22 .18 352 -1. .20 350 1.18 .17

chlorate) (XI) 0.45 g./mol AgX. 7840 10,15-Diaza-9,l6-dioxotetracosane-1,24-b1s-(pyridmium per- 357 1.25 .19 359 1.15 .19 354 1. 33 .17

chlorate) (XI) 0.75 g./mo1 AgX. 7841 10,15-Diaza-9,lfi-dioxotetracosane-l,24-bis-(pyridimumper- 358 1.38 .19 361 1. 20 .20 356 1.28 .17

chlorate) (XI) 1.2 g./mol AgX.

that the emulsions containing compounds X and XI of the invention were more stable thanthe emulsions containing the alkylene bis-pyridinium compound of the prior art.

EXAMPLE 6 The use of the bis-quaternary salts of the invention in color photography is illustrated in this example.

A sulfur and gold sensitized gelatino silver bromoiodide emulsion was ripened to maximum sensitivity. To this emulsion was added an optical sensitizing dye that extended the light sensitivity to 6000-7000 A. and a hydrophobic cyan color former suitably dispersed in a high boiling organic solvent. A portion of this liquid emulsion received no further treatment; to another portion was added one of the compounds described below. Both portions were coated on film support, and the dry films were exposed to red light in an intensity scale sensitometer. The exposed films were processed in reversal Color Process 1 and in the 5248 Negative Color Process 2 with the results shown in the following table. Color Process 2 was carried out as described by Hanson and Kisner JSMPTE, 61, 667-701 (1953) for Color Negative Film, type 5248 involving the steps of color development,

The color developing solution above had the following composition:

The silver bleaching solution above had the following. composition:

Water F. (32 C.) liters 1.0 Potassium dichromate grams 5.0 Potassium ferricyanide do 70.0

Potassium bromide do Determined by measuring the shift of the reversal dye curve on the log E axis at a given density below maximum density.

1 Determined by measuring the shift of the negative dye curve on the log E axis at a given density above minimum density.

EXAMPLE 7 A high-speed bromoiodide emulsion chemically sensitized with sulfur and gold compounds and optically sensitized with a cyanine'fidyewas-providedr Tcr'various' mg, (3) the second digestion or after-ripening;-to olgvtairi increased, sensitivity (Mees, ,The Theory of, the Photo: graphic Process,-1942,,page'3). The sensitizing agents may be added 'ataiiy 'stage,,preferably after the final. digestion.

The photographic'emulsions whiclijwe'use are'fof 'the developing-out'type' and bestresults have been obtainedv with gelatino-silve'r bromoiodide emulsions. ewever,

emulsions of varying silver halidecontent maybe usedi,

The emulsions arechemically sensitizedbyany of the accepted procedures in addition to sensitizing with the bis-quaternary salts of the invention. The emulsions may be digested with naturally active gelatin, or sulfur compounds may be added such as those described in Sheppard U.S. Patents 1,574,944 and 1,623,499, andSheppard and samples of the emulsionwere added thegingredients shown-= in the following table-' Sensitometiic 'evaluation of the samples was carriedoiifas imEiia'mple 1 with the result shown in the table:

TABLE-V||- Number Feature Speed jy Fog 1212 Control 304 1.14 .08 1214 4,11-Diaza-3,12-dioxotetradecane-L1 1-' 1 313' 1.42 .10

' 1s(pyridiuium perchlorate) (I) .75

g./mole AgX. ,7 V 1216 2,13-Diaza-3,12- ioxotetradeeane-LM- 310 1.26 10 bis-(pyridinium' chloride) (Ir) .75- gJmole AgX. V 1217 4-Hydroxy-G-methyl -1,8,3a,7-tetra j 309 1.2% .08

zaindene (XXX) 3.0 g./mol AgX." 7 (XXX) 8.0 g ./mol+ (I) .75 g./mol AgX, 314; 1123. 10 (XXX) 3.0 g./mol+(I) 3,0 g./mol Ag-X- 321 1. 17 10 s x? 3.0 g./ oi :.75=-g.lmol:; 311' 1.22 .10 g r (XXX) 3.0 gJmQH-(Ir) 3.0 g.lmol 312 1.19 .11

AgX.

color film containing couplersinthe emulsion-layers'was developed fther'cin," speed increases were 'obtainedparticularly for the greenand'i'ed-sensitive emulsiontiayers.

As indicated in the above examples,itmay be desirable to incorporate a stabilizing agent into the emulsion sensitized'with'the bis-quaternary salts of-the invention .towredu'ce fogitoj'normaljlevels'l 'Azaindenes particularlysuib able forthis purpose are those described the patrol et al'; U.S. 'patent application Serial'No s. 627,135 and 627; 186;,file'cl- Dec. 10, 195 6,1- foneiample-fthe' following: 5-

carboxy 4 hydroxy-l,3,3a,7-tetrazaindene 1,2 bis(4= Brigham;U.S. Patent 2,410,689

The emulsions may also be treated with salts of the noble mans such as ruthenium, rhodium, palladium, iridium and platinum, all of which belong to group VIII of the periodic table of'elements and have anatomic weight greater than 100. Representative compounds are ammonium chloropalladate, potassium chloroplatinate and sodium chloropalladite, which are used for'sensitizing:

in amounts below that which 'produc'esany substantial rag inhibition, as described in Smith and Trivelli II-.8; Patent-i 2,448,060, and as anti-,foggants in highe'r amounts, as de:. scribed in'Trivelli and Smith U.S'; Patents 2,566,245'aiid The emulsions may also be-chemically 'sensitized with. gold salts asrdescribed inwalle'r" and-D'odd-KJLS. Patent.

2,399,083 j or stabilized with gold; -salts;"-as}-de'scribed iu' Damschroder US. Patent 2,597,856and Yutzy'and Leer makers US; Patent 2,597,915. Suitablefcom'pounds potassium chloroaurite; potassium -aurithiocyanate, p9 tas'sium chloroaurat'e'," aurictrichlorid andx2aur6si1lfo benzothiazolemethochloride. J The emulsions may also be chemically sensitized with reducing agents such as stannous salts (Carroll U.S. Patent 2,487,850), polyamines such as diethylene triamine (Lowe and Jones U.S. Patent 2,518,698), polyamines such as spetmine (Lowe and Allen U.S. Patent 2,521,925), or bis-(*fl-anrinoethyl) sulfide and'rits waten solubleisalts (Lowe andJones; U.S;1Patent-2,521,926); v. Other compounds useful:for-,suppressingJthe-iogdcivl: of the emulsion sensitized with the bis-quaternary;:con'1-;-'v pounds of the invention include the mercury compounds of Allen et a1. U.S. Patent 2,728,663, Carroll and Murray U.S., Patent 2,728 ,664. and *Leubner and .Murray U issf'P-atent 2,728,665 granted Decernber'27, 1955; 'andthetorganic': mercury compoundsofiCarroll ethltUSl-Patent 2,784,090 granted'March%5;.1957: T a

- The emulsionsmay.: also-. contain polyalkylenaioxide's andiderivatives .there'o'fl-sucli as the-polyethyleneiglycolsg=- in addition: to the: bis=qu aternary;compounds10f the inven' tion'; Suitable:polyalkylenevoxides andpolyalkylene oxide derivatives arezde'scribedsin-Blake :US: fPatent r2;441;389;1 May 11,- l94.8',--:Blake etalt UzS;v Patents 2,400 532; May: 21, 1946, 2,423,549, July. 85, 11947, and lennings iet-ale'UsSzi Patent-2,577,127, December 4;'19-5'1.i

- Other stabilizing v agents may bezaddedtdttliezemnlsions containing the bis-quaternary 'sal't's isuellu-astheenietal'rin organic salts of-U.S.i patent; application Serial-'No. :493','043', filed :March=8, 1955,5by 'JJEJJones;

V The chemical-z sensitizing agents tangl other addenda 21 which we have described may; be used in valfiqnskindsoi photographic emulsions, e.g., various silver salts may be 17 used as the sensitive salt such as silver bromide, silver iodide, silver chloride or mixed silver halides such as silver chlorobromide or silver bromoiodide.

The dispersing agent for the silver halide may be gelatin or other hydrophilic material such as collodion, albumin, cellulose derivatives or synthetic resins.

Since the coupler-containing emulsions sensitized as described with the bis-quaternary salts are adapted particularly for use in color photography, they Will ordinarily comprise the emulsion layers of multilayer color films which emulsion layers are customarily difierentially sensitized to the primary regions of the visible spectrum and contain coupler compounds producing dye images of colors complementary to the sensitivity of the emulsion layers. In a representative color film, one or more of the differentially sensitized emulsion layers may be sensitized with the bis-quaternary salts, and in a typical example emulsions sensitized to the red, green and blue regions of the spectrum are superimposed on the support in that order and contain cyan, magenta and yellow color-forming coupler compounds respectively. A yellow filter layer is advantageously interposed between the blue and greensensitive emulsion layers.

Since the emulsion layers sensitized with the bis-quaternary salts of the invention may contain coupler compounds they can be readily processed by well known methods to yield color negatives directly or positive images by means of well known reversal processes. That is, after initial exposure of the emulsion to a subject a developer of the p-phenylene diamine type will produce a colored image negative in respect to the subject. Likewise, if development of the emulsion layer is first carried outwith a non-color-forming developer followed by reversal exposure of the residual silver halide and then color development, a colored positive is obtained as described in the examples above.

The coupler compounds used in the emulsion layers sensitized with the bis-quaternary salts, are any of the well known compounds which combine with the oxidation product of primary aromatic amino (p-phenylene diarnines) silver halide color developing agents to form dyes, for example, the phenolic couplers of U.S. Patents 2,266,- 452, 2,362,598, 2,589,004, 2,474,293, 2,521,908, 2,423,730 and Fierke U.S. patent application 476,561; the pyrazolone couplers of U.S. Patents 1,969,479, 2,369,489, 2,600,- 788, 2,618,641, 2,511,231 and the open chainv reactive methylene couplers of U.S. Patents 2,298,443, 2,652,329, 2,407,210, 2,271,238 and McCrossen et al. U.S. patent application Serial No. 575,099, filed March 30, 1956. Likewise, the emulsions may contain colored color-forming couplers as described in U.S. Patents 2,521,908, 2,706,- 684, 2,455,169, 2,694,703, 2,455,170 and 2,453,661.

The couplers may be dispersed in the emulsion layers by means of an oily coupler solvent according to the methods of U.S. Patents 2,304,940 and 2,322,027; However, if as may be the case, the couplers contain solubilizing groups such as SO H groups which render the couplers soluble in alkaline solution, the oily coupler solvent may be dispensed with and the couplers can be added to the emulsion from aqueous solutions as their alkali metal salts.

What we claim is:

1. A photographic silver halide emulsion containing a quaternary ammonium salt having a general formula of the class consisting of QRCONH (A) NHCR'Q' and QRCONHAQ' wherein Q and Q each represent radicals of the class consisting of wherein R, R3 and Re represent lower alkyl groups, Z represents the atoms necessary to complete a hetero, cyclic nucleus of the class consisting of pyridinium and q m, R and R e ch epre n alky en grou s linked directly to the quaternary nitrogen atoms, of fsaid radicals, n represents a positive integer of from 1 to 2, A represents a member of the class consisting of and r n n. and 11." p e n positive integers or. from about 1 to 10 there being from about 14 to, about '30 at ms p e nt in he h rtes l nea hain of atom i k said quaternary nitrogen atoms.

2. A photographic silver halide. emulsion containing a qu ternary sa avi g h en formula QRCONHANHCORQ': V wherein Q and Q each represent radicals of, the glass consisting of and wherein n and n" represent positive integers of from about 1 to 10, there being from 14 to about 30 atoms present in the shortest linear chain of atoms linking said quaternary nitrogen atoms.

I9 7 3. A photographic silver halide emulsion containing} quaternary ammonium salt having the general formula if? QRCONHANHCOR'Q' e wherein Q and Q each represent radicals of theclass consisting of wherein R3, R and R4 represent lower alkylgroups, Z represents the atoms necessary to complete aheterocyclic nucleus of the class consisting' of pyridininm and quinolinium, R and R each represent. alkylcne groups linked directly to the quaternary nitrogen atoms "of said radicals, A represents an alkylene group of from about 1 to carbon atoms, there being from about 14 to about 30 atoms present in the shortest-linear'chain of atoms linking said quaternaryfnitrogen atoms.

4. A photographic silver halide emulsion containing the compound 7 ,14-diaza 6,1'5-dioxoeicosane 1,20 bis(pyriperchloratefi 5. A photographic silver halide emulsion containing the compound 7,18-diaza-6,19-dioxotetracosane 1,24 bis (pyridinium perchlorate).

6. A photographic silver halide emulsion containing the compound 10,15-diaza-9,16-dioxotetracosane-1,24-bis (pyridinium perchlorate).,

, 7,, A photographic silver halide. emulsion containing the compound 12,15-diaza-11,16'- dioxohexacosane- 1,26- bis(pyridini1im perchlorate). 8. A photographic silverhalide emulsion containing the compound, 12,19-diaza- 11,20 dioxotriacontane-1',30 bis(pyridinium perchlorate). l J 1 9. The emulsion of claim 1 furthefcontaining a coupler compound reactive with the'oxidation products of a p-phenylcne diamine silver halide devcloping agent to forma'diei' i 10. The emulsion of claim 2 further containing a coupler compound reactive with the oxidation products of a p-phenylene diamine silver halide developing agent to form a dye.

11. The emulsion of claim} further containing a coupler compound reactive with the oxidation products of ap-phenylene diamine silver halide developing agent to form'adye.

'12. The emulsion of claim 1 further containing ,an azaindene stabilizing agent. l V 13. The emulsion of claim Z'further containingan azaindene stabilizing agent. i w

14. The emulsion of claim 2 further containing an azaindene stabilizing agent.-

15. Theemulsion of claim [wherein the silver halide is sulfurand gold sensitized-.- V

16; A method for increasing the speed of'a silver halide '5'20 emulsion which comprises developing said emulsionin the presence of a quaternary ammonium salt having a general formula of the class consisting of V QRCQNH(A) NHCOR'Q' wherein Q and Q each represent radicals of the class consisting of wherein R R and R represent lower alkyl groups, Z represents the atoms necessary to complete a heterocycliclnucleusof the class consisting of pyridinium and quinolinium,-R and R each represent alkylene groups linked directly to the quaternary nitrogen atoms of said radicals,'n represents a positive integer of from 1 to 2, A represents a member of the class consisting of 2)n' 2)n' n" V z)n- N a)a" 2)n"- I-( a)n' z)n" -'(CH,) 'COO(CH V z)nz)n'" cH ),,.NHcoNH(cH, -(CH 'OCONH(CH,)

and

wherein n and 11: represent ,positive integers of from about 1 to 10, there being firom about 14 to about 30 atoms present in the shortest linear chain of atoms linking said quaternary nitrogen atoms.

References Cited in the file of this patent UNITED STATES PATENTS 2,288,226 7 Carroll et a1. June 30, 1942 2,419,975 Trivelli et al May 16, 1947 2,784,090 Carroll Mar. 5, 1957 a f FOREIGN PATENTS 115,971

Australia Oct. 15, 1942 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No 2 9 iO 85l June 14 1960 Dorothy Ja Beavers et al0 It is hereby certified that error appears in the-printed specification of the above numbered patent requiring correction and that the said Letters Patent should read as corrected below.

Column 1 line 27 for "emulsions read emulsionse column 18 line 18 for that portion of the formula readin -=-(CH read -=(CH n column l9 line 51 for the claim reference numeral "2" read 3 column 2O line 30 for that portion of the formula reading =-(CH read Signed and sealed this llth day of April 1961a (SEAL) Attest:

ERNEST W. SWIDER ARTHUR W. CRQCKER attesting @flicer Acting Commissioner of Patents

Claims

1. A PHOTOGRAPHIC SILVER HALIDE EMULSION CONTAINING A QUATERNARY AMMONIUM SALT HAVING A GENERAL FORMULA OF THE CLASS CONSISTING OF