[1]2 o 7 3 4 2 9 0 0 United States Patent Office Patented Feb. 14, 1956 2,734,900 SENSrrIZING DYES AND METHOD OF PREPAIRATION 6 Donald W. Heseltine, Rochester, N. Y., assignor to Eastman Kodak Company, Rochester, N. Y., a corporation of New Jersey NoDrawin,-. AppHcationDecember28,l953, io Serial No. 400,810 14 Claims. (Cl. 260-240-5) This invention relates to photographic sensitizing dyes 15 and a w-ethod of preparing them. in my copending application Serial No. 400,809, filed on even date herewith, there is described a method of preparing new quaternary salts. These quaternary salts can be represented by the following two general formulas: 20 Ri 25 ,ind R2 Rs c 2 7-methoxy-a-naphthothiazole, 8-methoxy-c e-naphthothiazole, etc.), those of the benzoxazole series (e. g. benzoxazole, 5-chlorobenzoxazole, 5-phenylbenzoxazole, 5methylbenzoxazole, 6-methylbenzoxazole, 5,6-dimethylbenzoxazole, 4,6 - dimethylbenzoxazole, 5 - methoxybenzoxazole, 6 - me thoxybenzoxazole, 5 - ethoxybenzoxazole, 6 - chlorobenzoxazole, 5 - hydroxybenzoxazole, 6 - hydroxyb.- nzoxazole, etc.), those of the naphthoxazole series (e. g. a-naphthoxazole, pnaphthoxazole, etc.), those of the benzoselenazole series (e. g. benzoselenazole, 5- chlorobenzoselenazole, 5-methoxybenzoselenazole, , 5-hydroxybenzoselenazole, tetrahydrobenzoselonazole, etc.), those of the naphthoselenazole series (e. g. a.naphthoselenazole, 6-naphthoselenazole, etc.), those of the thiazoline series (e. g. thiazoline, 4methylthiazoline, etc.). British Patent 625,907, accepted July 6,1949, describes a method for making certain heterocyclic quaternary salts embraced by Formula I above. Also described in the British patent is a method of preparing photographic sensitizing dyes from these intermediates. However, the interniediates obtained according to the process described in my copending application Serial No. 400,809, are substantially pure and yield photographic sensitizing dyes which are likewise pure. Contrasted with the pure intermediates of my copending applicatiou, the intermediates obtained according to British Patent 625,907 are evidently contaminated with a material which interi-eres with certain dye condensations. For example, the, intermediates described in the British patent cannot be "Z' IE120 Cill So condensed with so-called ICI intermediates to produce dicarbocyanine dyes which can be isolated f-rom the rex c H whe rem i@' , represents an alkyl group, such as methyl ethyl, nprc@t)yl, isovropyl, n-butyl, isobutyl, p-hydroxyeth@i, car- 35 box yme'Lhyl, - carbethoxymethyl, g-riiethoxyethyl, benzyl (phe nylmethyl), allyl (vinylmethyl), etc., Ri represents a carbocyclic aromatic group, such as phenyl, o-, m-, and Ptolyl, o-, m-, and p-chlorophonyl, o-, m-, and p-hydro xyphenyl, o-, r@l- and p-methoxyphenyl, a-naphthyl, 40 ,8- naphthyl, 2,5-dimethylphenyl, p-dim ethylarninophenyl, pdiethylaminophenyl, 9-phenanthryl, etc., or a heterocycl ic radical, such as 2-thienyl, etc., R2 represents a hydro, -en atom or a methyl grotip, R3 represents a hydrogen alo m, an alkyl group, such as methyl, ethyl, n-propyl, 45 isop ropyl, n-butyl, isobi-11,Yl, benzyl (phenylmefllyl), etc., a monocyclic aryl grotip, such as phenyl, o-, m-, and ptolyl , p-methoxyphenyl, etc., or a furyl group, X represeiit s an anion, such as chloride, bromide, iodide, perchlo rate, thiocyanate, acetate, methylsulfate, ethylsulfate, 50 ben zenesulfonate, toluenesulfonate, etc., and Z represents the non-metallic atoms necessary to coniplete a heterocycl ic nucleus containing five atoms in the - heterocyclic rin-., such as those selected from the group. consisting of - methylthiathos e of the thiazole series (e. thiazole, 4 65 zoie, 5-methylthiazole, 4-phenylthiazole, - 5-phenylthiazole, 4,5-dimethylthiazole, 4,5-diphenylthiazole, 4-(2-thienyl)- thiazole, etc.), those of the benzothiazole series (e. g. benzothiazole, 4-chlorobenzothiazole, 5-chlorobenzothiazole, 6-chlorobenzothiazole, 7-chlorobenzothiazole, 4- 60 methylbenzothiazole, 5-methylbenzothiazole, 6-methylbenzothiazole, 5-bromobenzothiazole, - 6-bromobenzothiazole, 4-phenylbenzothiazole, 5-phenylbenzothiazole, 4- methoxybenzothiazole, 5-methoxybenzothiazole, 6-rnethoxybenzothiazole, 5-iodobenzothiazole, 6-iodobenzothiazole, 4-ethoxybenzothiazole, 5-ethoxybenzothiazole, tetra- 65 hydrobenzothiazole, 5,6-dimethoxybenzothiazole, 5,6-dioxymethylenebenzothiazole, 5-hydroxybenzothiazole, 6- hydroxybenzothiazole, etc.), those of the naphthothiazole series (e. g. a-naphthothiazole (i. e. 12,11-naphthothiazole, p-naphthothiazole (i. e, [1,21-n aphthothiazole), 5- 70 methoxy-p-naphthothiazole, 5-etho xy-p-naphthothiazole, action mixture. Accordingly, it is an object of my invention to provide a method for obtaining photographic sensitizing dyes from the intermediates represented by Formulas I and 11 above. Another object of my invention is to provide new photographic sensitizing dyes. A further object of my invention is to provide photographic sensitizing dyes which can be separated from their reaction medium iri substantially pure forin. Still another object of my invention is to provide photographic silver halide emulsions sensitized with optical sensitizing dyes obtained according to my new process. Other objects will become apparent from a consideration of the following description and examples. According to my invention, I realize the above objects by condensing together a compound selected ftom those represented by Formulas I and 11 above with a compound selected from those represented by the following general formula: wherein R4 represents an alkyl group, such as met@yl, ethyl, n-propyl, n-butyl, 6- hydroxyethyl, 8-methoxyethyl, carbethoxymethyl, benzyl (phenylmethyl), etc., (e. g. an alkyl group of the formula CmH2m+l wherein m is a positive integer of from I to 4), R5 represents a carboxylic acyl group, such as acetyl, propionyl, benzoyl, etc., R6 represents a mononuclear aromatic grotip of the benzene series, such as phenyl, o-, m-, and p-tolyl, etc., Xi represents an acid radical, such as chloride, bromide, iodide, thiocyanate, perchlorate, benzenesulfonate, p-toluenesulfonate, methyls-alfate, ethylsulfate, etc., d represents a positive integer of from I to 3, n represents a positive integer of from I to 2, and Zi represents the non-nietallic atoms necessary to cornplete a heterocyclic nucleus containing from five to six atoms in the heterocyclic ring, such as those selected from the group consisting of those of the thiazole series (e. g. thiazole, 4-methylthiazole, 4- phenylthiazole, 5-methylthiazole, 5-phenylthiazole, 4,5dimethylthiazole, 4,5- diphenylthiazole, 4-(2-thienyl)thia-
[2]2,734,900 3 zole, etc.), those of the benzothiazole series (a. g. benzothiazole, 4-chlorobenzothiazole, 5-chlorobenzothiazole, 6- chlorobenzothiazole, 7-chlorobenzothiazole, 4-methylbenzothiazole, 5-methylbenzothiazole, 6-me thylbenzothiazole, 5-bromobenzothiazole, 6-bromoben-7othiazole, 4-phenyl5 benzothiazole, 5-phenylbenzothiazole, 4-methoxybenzothi.izole, 5-metboxybenzothiazole, 6-met hoxybenzothiazole, 5-iodobenzothiazole, 6-iodobenzothiaz6le, 4-ethoxybenzothiazble, 5-etho)tybenzothiazole, tetrah ydrobenzothiazole, 516-dimethoxybenzothiazole, 5,6- dioxymethyler@ebenzothi- 10 azole, 5-hydroxybenzoLhiazole, 6-hyd roxybenzothiazole, etc.), thos-. of the naphthothiazole series (e. g. u.-naphthothiazole, p-naphtbothiazole, 5-methoxyp-naphthothiazole, 5-ethoxy-p-napbthothiazole, 8-methoxya-naphthothiazole, 7-methoxy-a-naphthothiazole, etc.), those of the ihianaph.15 theno-7',6',4,5-thiazole s6ries (e. g. 4'-rn@@ tioxvtl@i;-,tnarhtheno-7',6',4,5-thiazole, etc.), those of the oxazole series (e. g. 4-methyloxazole, 5-methyloxazole, 4-phenyloxazole, 4,5-diphenyloxazole, 4-ethyloxazole, 4,5 -dirqethyloxazole, 5-phenyloxazole, etc.), those of the benzoxazole series 20 (e. g. benzoxazole, 5-chlorobenzoxazole, 5-methylbenzoxazole, 5-phenylbenzoxazole, 6-methylbenzoxazole, 5,6-dimethylbenzoxazole, 4,6-dimetbylben-7oxazole, 5-methoxybenzoxazole, 5-ethoxybenz-oxazole, 5- chlorobenzoxazole, 6-methoxybenzoxazole, 5-bydroxybenzoxazole, 6- hydroxy- 25 benzoxazole, etc.), those of the naphthoxazole series (e. g. cc-naphtboxazole, p-naphthoxazole, etc.), those of the selenazole series (e. g. 4-methylselenazole, 4 -phenylselenazole, etc.), those of the benzoselenazole series (e. g. benzoselenazole, 5-chlorobenzosele-nazole, 5-m ethoxybenzoselena30 zole, 5-hydroxybenzoselenazole, tetr ahydrobenzoselena@ole, etc.), those of the nkohthoselenazole series (e. g. a-naphthoselenazole, 3-na,,ohthoselenazole, etc.), those of the thiazoline series (e. g. thiazoline, 4 -methylthiazoline, etc.), those of the 2-quinoline series (e. g. quinoline, 3- 35 methylquinoline, 5-methylquiniDline, 7-methylquinoline, 8-methylquin,oli-.ie, 6-chloroquinoL,'lle, 8 -chloroqtiinoline, 6-methoxyquinoline, 6-ethoxyquinoline, 6-hydroxyquinoline, 9-hydroxyquinoline, etc.), those of the 4-quinoEne series (e. g. qiiinoline, 6-r@iethoxyquinoline, 7-methylquino40 line, 8-methylquinoline, etc.), those of th-. 1-isoqLinoline series (e. g. isoquinoline, 3,4-dihydro,s-,ql-,inoliTie, etc.), those of the 3-isoquinoline series (e. isoquinoline, etc.), those of the benzimida-7ole series (e. g. 1,3-diethylbenzimidazole, 1-ethyl-3-phenylbenzimidazole, etc.), those of 45 the 3,3- dialkylindolenine series (e. _P,. 3,3-dimethylindolenine, 3,3,5-trimethylindolenine, 3,3,7- trimethylindolenine, etc.), the pyridine series (e. g. pyridine, 5-methylpyridine, etc.), etc. The photo,-rapbic sensitizing dyes obtained by con- 5o densing the compounds of Formula I or 11 with a compound selected from those represented by Formi-ila 11.1 can be represented by the following two general formulas - IV. ,Z@@ R-N@b-C-H=C-CH(=CIEC-CH)d=C(-Cll@CH)-t--@:-N-R4 and V. R2 R3 \ 0 / H2c c]12 zi % c H wherein R, Ri, R2, R3, R4, X, d, n, Z and Zi each have the values given above. The sensitizing dyes represented 70 by Formula V are new while certain of the compounds represented by Forinula IV are also ne,,iT. I have also found that new seiasitizinp, dyes can be advantageoiisly prepared by condersin-, a compound selected from those represented by Formula I or 11 with a com7,5 pound selected from those represented by the following general formula: VI. R70 0 I Rso wherein P,7 and RB each represent an alkyl group, such as methyl, ethyl, n-propyl, etc. Altematively, the vinylogous analogues of certain of these sensitizing dyes can be obtained by condensing a compound selected from those represented by Formula I with a compound selected from those represented by the formula: Vla. R"O-CH=CH-CH(OR')2 wherein R' and R" each represents an alkyl group, such as methyl, ethyl, etc. The products obtained by the condensation of the compounds represented by Formula I with those of Formula VI or Vla can advantageously berepresented by the fol10wing general formula: Vil. /Z" R-2@@b-C ll=C-0 R (=CII-CII),4=C -C I x icl Cl wherein R, Ri, X and Z each have the values given above, and in represents a positive integer of from I to 2. The seiasitizing dyes produced by the condensation of the compounds of Formula 11 with those of Formula VI can advantageously be represented by the following gelneral formula: Viii. R2 RI R2 Rs c Iz, H2d '@C112 CH2 "lz\ R-9@b-CH=cl @-Cla=CH-CIEE=@ @- CH=C'@'N-R Ix c c u H wherein, R, R2, R3, X and Z each have the values given above. I have also found that new sensitizing dyes can be obtained by condensing a compound selected from those represe@ted by Formula I or 11 with a compound selected from those represented by the following general formula: 0=6-'C=CH-N-R@ Ro Nvherein R5 and R6 each have the values given above and Q represents the non-metallic atoms necessary to complete a heterocyclic nucleus containing from 5 to 6 atoms in the heterocyclic ring, such as those selected from the group consisting of those of the thiazolinone series, for examdle: those of the 2,4 -thiazolidinedioiie series, such as 2,4- thiazolidinedione, 3-alkyl-2,4-thiazolidinediones (e. g. 3-ethyl-2,4-thiazolidinedione, etc.), 3- phenyl-2,4-thiazolidinedione, 3-a-naphthyl-2,4-thiazolidinedione, etc., those of the 2-thio2,4-thiazolidinedione (rhodanine) series, such as 3-alkyl-2-thio-2,4-thiazolidinediones (3-alkylrhodanines) (e. g. 3-ethyl-2-thio-2,4- thiazolidinedione), 3rhenyl-2-thi<)-2,4-thiazolidinedione, 3-a-naphthyl-2-thio2,4- thiazolidinedione, 3-(l-benzothiazyl)-2-th io-2,4-thiazolidinedione, etc., those of the 2- thio-2,- 5-thiazolidinedione series (e. g. 3-ethyl2-thio-2,5-thi.azoli - dinedione, etc,), etc., those of the 2-alkylmereapto-2-thiazolin-4-one series,
[3]2,784,906 5 such as 2-ethylmercapto-2-thiazolin-4-one, etc., those of the thiazolidinone series, such as 4-thiazolidinone or its 3-alkyl (e. g. 3- ethyl, etc.), 3-phenyl or 3-a-naphthyl derivatives, those of the 2- alkylphenylamino-2-thiazolin-4one series (e. g. 3- ethylphenylamino-2-thiazolin-4-one, 5 etc.), those of the 2- diarylamino-2-thiazolin-4-one series (e. g., 2-diphenylamino-2- thiazolin-4-one, etc.), those of the 2-thiazolin-5-one series, such as 2-ethylthio-2-thiazolin5-one, 2-benzylthio-2-thiazolin-5-one, etc.; those of the oxazolone series, for example: those of the 2-thio-2,4- 10 oxazolidinedione series, such as 3-alkyl (e. g. 3-methyll 3-ethyl, etc.)-2-thio-2,4-oxazolidinediones, those of the 2-imino-2,4- oxazolidinedione (pseudohydantoin) series, etc., those of the 2- oxazolin-5-one series such as 2-phenyl2-oxazolin-5-one,- 2-ethyl-2- oxazolin-5-one, etc., those of I r) the 2-isoxazolin-5-one series, such as 3-phenyl-2-isoxazolin-5-one, etc., those of the imidazolidinone series, for example: those of the 2,4- imidazolidinedione (hydantoin) or its 3-alkyl (e. @@. 3-ethyl, etc.), 3-phenyl or 3-a-naphthyl deri vatives, as well as its 1,3-dialkyl (e. g. 1, 3-diethyll 20 etc.), 1-alkyl-3-phenyl (e. .-. 1-ethyl-3-phenyl, etc.), Ialkyl3-naphthyl (e. g. I-ethyl-3-a-naphthyl, etc.), 1,3-diphenyl , etc. derivatives, those of the 2-thio-2,4-imidazolidinedi one series, such as 2-thio-2,4-imidazolidinedione (2- thiohydant,oin) or its 3-alkyl (e. g. 3-methyl, 3-ethyl, 25 etc.), 3-phenyl or 3-a-naphthyl derivatives, as well as its 1,3- dialkyl (e. g. 1,3-diethyl, etc.), I-alkyl-3-phenyl (e. g. 1-ethyl-3-phenyl, etc.), I-alkyl-3-naphthyl (e. g. 1- ethyl-3-u-naphthyl, etc.), 1,3-diphenyl, etc. derivatives, those of the 2-alkylmercapto-2-imidazolin-5-one series, 30 such as 2-n-propylmercapto-2-imidazolin-5-one; those of the thianaphthenone series, such as 3(2H)-thianaphthenone or 2(3H)-thianaphthenone; those of the pyrazolone series, such as pyrazolone or its 1-alkyl (e. g. 1-methyl, Iethyl, etc.), 1-phenyl, 1-naphthyl (e. g. 1-a-naphthyl), 35 3-alkyl (e. -. methyl, ethyl, etc.), 3-phenyl, 3-naphthyl (3-anaphthyl), I-alkyl-3-phenyl (e. g. 1-methyl-3-phenyl, etc.), 3-alkyl-l-phenyl (e. g. 3-methyl-l-phenyl, etc ), 1,3- dialkyl (e. g. 1,3-dimethyl, etc.), 1,3-diphenyl, e'tc. deriva tives; those of the oxindole series, such as 2,3- 40 dihydr o-3 -ketoindole, and like five-membered heterocyclic nuclei; those of the 2,4,6-triketohexahydropyrimidine series, for example, 2,4,6-triketohexahydropyrimidine (barbit uric acid), 2-thio-2,4,6-triketohexahydropyrimidine (2- thiobarbituric acid) as well as their I-alkyl (e. g. 1- ethyl, etc.) or 1,3-dialkyl (1,3-diethyl, etc.) derivatives; 45 those of the 3,4-dihydro-2(IH)-qiiinolone series, such as 3,4- dihydro-2(lH)-quinolone (dihydrocarbostyril); those of the 3,4-dihydro-2(IH)-quinoxalone series, such as 3,4- dihydro-2(IH)-quinoxalone (oxydihydroquinoxaline) - benzoxaetc.; those of the 3-phen<)morpholone (1,4,2H ' 50 zine-3(4H)-one or benzo-g-morpholone) series, such as 3-phenomorpholone, etc.; those of the 1,4,2H-benzothiazine-3(4H)-one (ketodihydrobenzoparathiazine) seri F S, such as ketodihydrobenzoparathiazine, etc., and like six55 membered heterocyclic nuclei. The new sensitizing dyes obtained by condensing the compounds of Forinula I or II with those of Formula ix can advantageously be represented by the following general formulas: 60 X. z, P.-N-6=CH-C=CH-CH=6-6=o I and Ki 65 Xi. Rs Ra ,z, H2c CH2 R-N/-b@CH-C C=CIE-CH=C'-@=o .70 c H wherein R, Ri, R2, R3, Q and Z each have the values given above. Attematively, the compounds of Formula V above 75 r3 wherein d is 2 can be prepared by condensing a cohi@ pound selected from those represented by the following general forinula: X ii. R 2 R 3 c /Z \ H 2c C H2 R -N@6- CH= C -CH=CIEE-CH=CH-N-R5 I \ :@-I I x c R o n wherein R, R2, R3, R5, X and Z each have the values given above, and Rg represents a monocyclic aromatic group, such as phenyl, tolyl, etc., with a compound selected from those represented by the following general formiila: xiii. -ziR4-N(@C]EI-CH).-i@-c-CH3 I xi wherein R4, Xi, n and Zi each have the values given above. The conipounds selected from those represented by Formula XII above can be prepared by heating together in the presence of a carboxylic anhydride a compound selected from those represented by Formtila II with a compound selected from those represented by the followin@ general formula: Vlb. Rg-NH-CH=CH-CH=N-Rio wherein Rg has the values given above and Rio represents an aryl group, sucli as phenyl, o-, m-, and p-tolyl, etc. The condensation of the compoiinds represented by Formulas I and 11 with those represented by Formulas 111, VI, Vla, Vlb, and IX, or those of Formula XII with those of Formula XIII, can be accelerated by heating. The particular temperature used can be varied, depending on the boiling point of the reactants. Advantageously, these condensations can be carried out in the presence of an inert medium, such as pyridine, quinoline, 1,4dioxane, etc. Except for the condensation of the conipounds of Formula 11 with those of Formula Vlb which is carried otit in the preseiice of a carboxylic anhydride, such as acetic anhydride, propioilic anliydride, bt,.tyric anhydride, benzoic anhydride, etc., the lower aliphatic alcohols have also been found to be effective diluents. Typical lower aliphatic alcohols include ethanol, ii-propanol, n-butanol, isoptopanol, isobutanol, etc. The condensation of the compotinds of Formula I or 11 with those represented by Formulas III or IX, or the condensation of the compounds of Formtila Xil with those of XIII can advantageously be carried out in the presence of a basic condensing agent. Typical agents include, for example, the trialkylamines (e. g. triethylamine, tri-npropylamine, triisopropylamine, tri-n-butylamine, t riisobutylamine, tri-n-amylamine, etc.), the Nalkylpiperidines (e. g. N-methylpiperidine, Nethylpiperidine, etc.), the N,Ndialkylanilines (e. g. N,N-dimethylaniline, N,N-diethylaniline, etc.), etc. The following examples will serve to illustrate more fully the manner whereby I practice my invention. Exainple I.-3,3'-diethyl-9-(I-naphthyl)-thiadicay-bocyaitine iodide s C-CII=C'CH=CH-CH=C N@e \N@) c 2H@ c SH5 3-ethyl-2-(2-a-naphthylpropenyl)benzothiazolium iodide (I mol., 0.76 g.), 2-pacetanitidovinyl-3-ethylbenzothiazolium iodide (I mol.+10%, 0.83 g.) and triethylamine (I mol.+100%, 0.5 ml.) were dissolved in ethyl alcohol (10 ml.) heated tinder reflux for fifteen niinutes,
[4]7 The re@ac@tjqli mix-ture was -thqti,,O@lle4 ov@tm,ight, ffitered e Y w4s4@d vr.,ith wafer- inq c@thy-l'@lc'o,@ qnd tike @crad d e w 4s hol and dried. After two recrystallizations fro m tli'yl -.., I M. e alcohol, the yield of purified dye was 0.65 g. (61@o), , M. P. 240-241' C. dec. Exaniple 2.-3,3'-diethyl-ll-(I-itaphth yl)-oxathiadicarbocyanine iodide s 0 C-CH=C-011=CH-CH=C N/U I C2 C 2H5 3-ethyl-2-(2-u-naphthylpropenyl)benzothiazolium iodide (1 mol., 0.76 g.), 2-pacetanilidovinyl-3-ethylbenzoxazolium iodide (i mol.+10%, 0.80 g.) and triethylamine (I mol.+100%, 0.5 ml.) were dissolved,in ethyl alcoholl (10 ml.) and h,-ated tinder.refl-Lix for fifteen mi-iiutes. The reaction mlxttire was then chilled overnight, filtered, and the crude dye washed with water and drie, I d. After two recrystallizations from methy alcohol, the yield of puiifiid dye was 0.38 g. (37%), M.,P. 204-205' C. dec. Anal.-Caled. for C33H?,gIN20S: 1, 20.2. Found: 1, 20.5. Exatizple 3.-3,3'-dfethyl-9,13-di(I-iia phthyl)-thiatricarbocyanine iodide C-CH=C-CH=CIEI-CR=C-CH=C I \ N c2HS I 3-ethyl - 2 -(2-m-naphthylpropenyl)benzothiazolium iodide (1 mol., 1.52 g.'@, and d;.ethoxymethyl acetate (I 0 ml.) mol.+200%, 1.62 g.) wcre dissolved iii pyridine 1 and heated under reflux for three minutes, Water (2 ml.) was added with stirring to the hot reaction mixture and it was then chilled overni-,ht. The crude dye was filtered off, washed thoroughly with water and ether and dried. After tv@,o recrystallizations from methyl alcoliol, the yield of purifi,-d dye Nvas 0.34 @@. (27%), M. P. 223-224- C. dee. Exat?iple 4.-3,3'-diethyl-9,15-di(I-na plithyl)-thiatetracarbocyaiiiiie iodide s \C-CH=C-CH=OH-CH=Cll-CH=C-CH=c V\N c2H5 I @2H5 3 -ethyl - 2 - (2-a-naphthylpropenyl) benzothiazlolium iOdide (I mol., 1.52 g.) and 1,1,3- trimethoxypropene ( I mol.+100%, 1.3 g.) were dissolved in pyridine and then heated rapidly to reflux temperatlire. The reaction mixture was heated under reflux for sixty seconds and then the crude dye was imritediately thrown out of soltition bY the additioii of water (50 ml.). The crude dye was then filtered c,@T- and thorou hly washed with,,.@,@ater, ether,.and fin,dly methyl alcohol. After tnvo recrystallizat;.ons froi-n acetone, the yield of purified dye was 0.23.g. (18%), M. P. 206-207' Ci dec. .8 4-ya 5.77-73-@ethyl-.5!![.4:-,(j-:ethyl7.2(@H)4qq;p@h4qzo tyliih 17@--@i;t'enyl*-@] e)-3.7.,(I-n4@ @ @Tkq4qnine 0 c2H5 11 i-@ ' s C=CIEE-C=OH-011=C C=S s 3 ethyl - 2 - (2 - o& - naphthylpropenyl)benzothiazolium iodide (I mol.,- 0.76 g.) ' 5-acetanilidomethylene-3-ethylrhodanine (I moi.@-io%, 0.56 g.) and triethylamine (I mol.+100%, 0.5 ml.) were dissolved in pyridine . (10 ml.) and heated under refltix for fifteen minutes. Methyl alcohol (100 ml.) was added with stirring to the reaction mixture and it was then chilled overnight. The crude 20 dye Nvas filtered off, washed well with methyl alcohol and dried. After two recrystallizations from pyridiiie and rnethyl alcohol, the yield of ptirified dye was 0.63 g. (76%), M. P. 256-257- C. dec. Anal.--Calcd. for C28H24N2OS3: C, 67.0; H, 4.8. 25 Found: C, 66.6; H, 4.9. Example 6.-4-[4-(3-ethyl-2(,3H)benzot hiazolylidene).!3- (I - 7,zaphtity.1) - 2 - butenylidene] - 3 - niethyl - I phenylpyrazolone 00 0 06HS b i I s -N v \ C=CH-C=011-C]1=0 N 3 - ethyl - 2 - (2 - a - naphthylprgpenyl)benzothiazol 40 ium iodide :(l mol., 0.76 g.), 4-acetanflidomethyle ne-3met4yl-l-phenylpyrazolone (I mol.+10%, 0.58 g.) and trieth amine (1 mol.+100%, 0.5 ml.) were dissolved yl in pyridine (10 i-ni.) and heated under reflux for fifteen minutes. The reaction mixture was diluted with 200 ml. 45 of aqueous methyl alcohol and chilled overnight. The crude product was filtered off, washed with water and dried. Aiter two recrysta'llizations from ethyl alcohol, the'yield of purified dye was' 0.36 9. (43%), 258-259' C. dec. 50 Example 7.-3, 3'-dietliyl-9-phenylthiadicai-bocyanine iodide 55 C-CH=C-CH=Clff-CH=C 60 C2H& @I 3 - ethyl - 2 - (2 - phenylpropenyl)benzothiazolium - ptoluenesulfonate (I mol., 0.75 g.), 2-,8-acetaniUdovinyl-3ethylbenzothiazoliurn iodide (I mol., 0.75 g.) and tri65 ethylamine (2 mols., 0.5 cc.) were dissolved in ethyl. alcohol (10 ml.) and heated under reffiix for fifi@en minutes. The crude dye was then thrown out of solution by the addition of water (50 'ml.), the aqueous solution decanted and the dye dissolved in acetone (15 ml.). The 70 dye,was twicp more thrown out I ci solution with,water and di I ssolved in hot acetone. The fina . I acetone solution was chilled overnight and the crystalline dye filtered off and dried. After two recrystallizations from acetone, :the yield of purified,dye Was 0.41 g. (42%), @M. P. 75 195-196' C. dec.
[5]9 ExamPle 8.--3, 3@-diethyl-9, 13-diphenylthiatricarbocyanine iodide C-CH=C-CH-CH-CH=C-CH=C / Y/ N 'Z 41,E@ 3 - ethyl - 2 - (2 - phenyl)propenylbenzothiazolium - ptoluenesulfonate (I mol., 1.50 g.) and diethoxymethyl acetate (I mol.+50OVo, 1.62 g.) were dissolved in pyridine (10 ml.) and heated rapidly to boiling. The reaction mixture was heated under refltix for two minutes. The crude dye was converted to the iodide by the addition of sodium iodide (1 g. in 10 ml. water). After chffling overnight, the crude dye was filtered off, washed with water and ether and dried. After two recrystawzations from methyl alcohol, the yield of purified dye was 0.29 g. (25%), M. P. 202-203' C. dec. Anal.-Calcd. for 18.3. C371-b3IN2S2: 1, 18.23; Found. Example 9.-3-ethyl-5-[4-(3-ethyl-2( 3H)benzothiazolylidene) -3-phenyl-2-butenylidenel-l-rhodanine s 0 -N-C 2H5 @2III 3 - ethyl - 2 - (2 - phenyl)propenylbenzothiazolium P toluenesulfonate (I mol., 1.13 g.), 5- acetanilidomethyle,ne-3-ethylrhodanine (I mol.+10%, 0.84 g.) and triethylamine (2 mols., 0.5 cc.) were dissolved in pyridine (10 ml.) and heated under reflux for ten minutes. Methyl alcohol (100 ml.) was added to the reaction mixture with sdrring and it was then chifted overnight. The crude dye was filtered off, washed with methyl alcohol and dried. After two recrystallizations from pyridine and methyl alcohol, the yield of purified dye was 0.75 g. (68%), M. P. 189-190' C. dec. Anal.-Calcd. for C24I-L2N2OS3: C, 63.96; H, 4.92. Found: C, 63.9; H, 4.9. Example 10.-3, 3'diethyl-9, 11-neopentylenethiadicarbocyanine iodide CHs CH3 \ C / s C@2 \CH2 s 0 @-C C- 131=@ \ C H=C N if C 2HS I @2Hs 3 - ethyl - 2 - (1, 5, 5 - trimethyl - 3 - cyclohexenyli dene)methylbenzothiazolium iodide (1 mol., 0.85 g.), 3-ethyl-2-ethylmercaptobenzothiazolium ethyl sulfate (I mol.+100%, 1.40 g.), and triethylamine (1 mol.+100@o, 0.5 in].) were dissolved in pyridine (10 ml.) and heated under reflux for fifteen minutes. The reaction mixture was chilled and stirred with water (50 ml.) and ether (100 nil.) and then chilled overnight. The crude dye was filtered off, washed with water and ether and dried. After two r ecrystallizations from methyl alcohol, the yield of purified dye was 0.55 g. (47%), M. P. 215-216' C. dec. 2t784,900 10 Example ll.-3, 3'-diethyl-11, 13-neopentylene-axa-thiatricarbocyanine iodide Cus CHs 0 H2C Cli C-CH=@ 10 l@ \C@Hs 3 - ethyl - 2 - (1, 5, 5 - trimethyl - 3 - cyclohexenyl, idene)methylbenzothiazolium iodide (I mol., 0.85 g.), 15 2-,6-acetanilidovinyl-3-ethylbenzoxazolium iodide (I mol., 0.87 g.) and triethylamine (2 mols., 0.5 ml.) were dissolved in pyridine (10 ml.) and heated under reflux for five minutes. The reaction mixture was cooled, stirred with water (50 ml.) and ether (100 ml.) until the dye 20 started to crystallize and was then chilled overnight. The crude dye was filtered off, washed with water and ether and dried. After two recrystallizations from methyl alcohol, the yield of purified dye was 0.21 g. (18%), M. P. 223-224' C. dec. 25 Example 12.-3, 3'-diethyl-9, 11-neopentylenethiatricarbocyanine iodide C H3 C HS \ 0 / 3 0 s H 20 C H2 \\ CCH=@ - CH=CH-CH=c \ C // V\Nll 11 NIV 3 5 0 2HS \1 6 2H5 3-ethyl-2-(l, 5, 5-trimethyl-3-cycloh exenylidene)methylbenzothiazolium iodide (I mol., 0.85 g.), 2-p-acetanilidovinyl-3-et hylbenzothiazolium iodide (I mol., 0.90 g.) 40 and triethylamine (2 mols., 0.5 ml.) were dissolved in pyridine (10 ml.) and heated under reflux for five minutes. The reaction mixture was then cooled and water (50 ml.) and ether (100 ml.) added with stirring and the reaction mixture chilled overnight. The crude dye was Mtered off, washed with water and ether and 45 dried. After two recrystallizations from methyl alcohol, the yield of purified dye was 0.88 g. (72%), M. P. 219-220' C. dec. Exaniple 13.-3, 3'-diethyl-9, 11-neopentylene50 thiatetracarbocyanine iodide CH3 CH3 \ C / 5 5 11 2C C H2 \ CCH=@ - CH=Cif-CH= I CH-CH=C C H N 60 C2]15 I 3-ethyl-2-(1,5,5-trirpethyl-3-cyclohexenylidene)methylbenzothiazolium iodide (I mol., 0.85 g.), 2-(4-anil inobutadienyl)-3- ethylbenzothiazolium iodide (I mol., 0.87 g.) triethylamine (2 mols., 0.5 ml,) and acetic anhydride (I (5 mol., 0.21 ml.) were dissolved in ethyl alcohol and heated under reffux for five minutes. The crude dye was thrown out of solution by the addition of water (50 ml.) and ether (200 ml.) and the mixture was chilled overnight. The water and ether solutions were decanted and the 70 crude dye stirred with ethyl alcohol (50 ml.) until crystallization started. The mixture was then heated to boiling and chilled overnight. The crude dye was filtered off, washed with water and ether and dried. After two r ecrystaflizations from ethyl alcohol, the yield of purified dye 75 was 0.51 g. (40%), M. P. 198-199' C. dec. - .
[6]12 E@@ampZq. 14.@.3,3'-diethy,1-9,@l-neop@antyteke-thiapentacqrkqcyqtg'49 iodide CH: CH3 lys\ lr2C C112 s C-CH=@ @-CIEE=CH-CIE=CH-C]31=CH-CH==C \ c H 2H5 3-ethyl-2-(1,5,5-trimethyl-3-cyclohexenylidelie)methyl- perature. The reaction was removed from the heat and benzothiazolium iodide (2 mols., 1.70 g.), 2-(6-acetanilidiethoxy;pp@hyl a a e (1 mol.+300%, 3.2 g.)- q4d tri dohexatrienyl)-3- ethylbenzothiazolium-p-toluenesulfonate ethy,!4mine (I @mql.+Ioo% 1.4 ml.) were added in that (I mol., 1.0 g.) and triethyla ine (2 mols., 0.5 ml.) we order. The reaction mixture was allowed, to cool slow m re jy@ dissolved i-n ethyl alcohol (20 ml.) and ra idly heated in the dark fo one hour, a d wa then poured .P -n S- , , i.nto @a to the reflux te@nperature. Reff . beaker and. water (100 ml.) and ether (100 ml.) -*yfre I uxing was continued for two minutes and then the reaction mixture was allowed added with stirring. The stirring was continued unti crystallization started and the mixture was then ch@i@A to cool slowly to room tg@mperature. After chilling for for one hour. The c d dye was filt red off, washed two hours, the crude dye was filtered off, washed with 20 e @e Nvith water and ether and boiled with methyl 41cq4pl, water and ether and dried. After two recrystaflizations chille o r igh it r d ve n fi ered and dried. Afte two recrvs talfro m methv l alcoho l. the Yield of t)urifie d dyp was 0.15 lizati'o ns from methy j alcoh 1, the yi4@l d, of pi@Tif ied Oye 0 g. (11%), M. P. 1195-196' C. dec. weks 0.17 g. (5%), M. P. '203-4' C. dee. Example 17.-3,3'-diethyl-9,11-neopentylene-4,5-benz othiap@entacarbqcyanine lod@de CH3 CE[3 \ C / H2C CH3 CCH=@ @- CH=CH-Cll=OH-Cl[=CH-CIEE=C C H C2115 1 Example 15.-I-ethyl-5-(6-(3-e@ hyl-2(3H)benzothfqzqlylidene-3,5-neopentylene-2,4-hexadienvlidenel-2-thiobarbittiri'c acid CH3 CII3 0 C.-Hz 40 S H2c CH2 C=CH-@ C=CH-CH=C C=s @@ / C 45 (N\l H C-NH U2Ji5 0 3-ethyl-2-(1,5,5-trimethyl-3-cyclohexenylidene)methylbenzothiazolium iodide (1 mol., 0.85 g.), 1-ethyl-2-thiobarbituric acid (1 mol.+20%, 0.41 g.), diethoxymethyl 60 acetate (I mol.+50%, 0.5 ml.) and - triethylamine (2 mols. 0.5 ml.) were dissolved in pyridine (10 nil.) and heated under reflux for five minutes. At this time an additional 0.5 ml. of diethoxymethyl acetate and 0.5 ml. of triethylamine were added and reiluxin was continued 55 ,9 for an additional five minutes. Then 100 ml. of 50% aqueous methyl alcohol was added with s tirring and th e reaction mixture was chilled overnight. The crude d .ye was filtered off, washed with methyl alcohol and, dried. After two recrystallizations froni pyridine and methyl al(;o cohol, the yield of purffied dye was 0.30 g. (31%), M. P. 275-276' C. dec. Exariiple 16.-3,31-diethyl-9,11; 15,17-dineopentylenethia-pentacarbocyanine iodide CH3 CIE[B CHS CTT3 65 / I 0 C HI(@ \CH2 C=CH-C H- C=CIE 70 IC C N II H N C 2HS I 37-ethyl-2-(1,5,5rtrimethyl-3-cyclohexe.nylidene)me thylbenz.othiazolium iodide (@ mol., 4.25 g.) was dissolvg,,d in pyridine (25, ml.) and the: mixture lic@ated to reflux tem- 7 I-ethyl-2-(1,5,5-trimethyl-3-cyclohexenylidene)meth ylnaphtho[1,2]thiazolium iodide (1.90 g@, I mol.), 2-(6acetanilidohexatrienyl)-3-ethylbenz6thiazolium P sulfonate (2.17 gi, I mol.) and triethylamin (1.4 ml., ,P 1 mol.+150%) were dissolved in ethyl alcohol (25 ml.) and heated to reflux. The reaction mixttire was affowed to stand for two hours without further heating and was then chilled ovemight. The crude dye was filtered off,, washed 'with water and ether, and dried. T@he dye was stirred with boiling me@4yl alcohol (100@ ml.), chilled, filtered and dried. The yield of penta-@arbocyanine iodide 1 was 0.23 g. (8%). M. P. 194-5' C. dec. Example 18.-3,3'-diethyl-9,11-neopeiitylene-selenatrica,-bqcyanine iodide CH3 CH& s(i C \ So H2c CH2 @-CH=CH-CH= C NI (2@5 3-ethyl-2-,(1,5,5-trhneth3rl-,-3-qypIghp7@qnylidene)methylbenzo" I iodide (1.18 g., 1 mol.), 2-0-kqe@@gidoyl -@,ret4ylbenzoselenazolium- iodide (1.24 g., I mol.) I . - ;iyj and triethylamine (0.7 ml., I mol.+100,7o) -vyer@-@tssolved in ethyl alcohol (15 ml.) and heated,under reflux for fifteen niinutes. The cruae dye was thrown o ut of solutio by the addition with stirring of water (100 @nL) and:ether. (@PO ml.). Thp pr@oduct was then filtered pff, N,@4sh wgc@r- A110, qthq-r, q4d dried. After two reqryqt;klli atio from ;4pthyl, alcohol, thp yield of pgte dye was 0.68 g. (39%). M. P. 207-S' 0. dec.
[7]2,784,900 13 14 Exatnple 19.-5,5@-dichloro-3,3@-diethyl-9,11; 15,17- dineopentylenethiapentacarbocyanine iodide CHO CI[3 clr3 CH3 \ 0 / \ c s H20 CII2 H30 CH2 C-CH=@ @-CH=C]I-CE[=@ -CH=C c 1-.[ \0 @ol \ c :@-I ol N@ H ]El N &H, 5 - chloro - 3 - ethyl - 2 - (1,5,5 - trimethyl - 3 - cyclom ethylbenzothiazolium iodide (O 41 g., I mol.), 2-p-anilhexenylidene)methylbenzothiazolium iodide (2.51 g., I in obutadienyl-3-ethyIbenzothiazolium iodide (0.43 g., I mol.) and diethoxymethyl acetate (1.62 g., 1 rnol. m ol.), acetic anhydride (0. II n-A. I mol.), and triethyl+ 300%) were dissolved in pyridine (15 ml.) and the 20 a mine (0.28 ml., I mol. + 100%) were dissolved in reaction mixture heated rapidly to boiling. The reaction mixture was then allowed to cool slowly to room et hyl alcohol (10 ml.) and heated under reflux for temperature, and the,crude dye was thrown out of got wenty minutes. The crude dye was thrown out of solution by the addition with stirring of water (100 ml.) fu tion by the addition of water (100 ml.) and ether (100 and ether (100 nil.). The water and ether were then 25 Ml.). The crude dye was filtered off and then stirred decanted and the residue stirred with acetone until cryswi th a little methyl alcohol until crystalline, chilled, talline, chilled, filtered, and the crude product dried. After two recrystallizations from methyl alcohol, the fil tered, and dried. After two recrystallizations from yield of pure dye was 0.10 g. (5%). M. P. 205- 6' m ethyl alcohol, the yield of pure dye was 0.10 g. (16%). C. dec. 30 M. P. 203-4' C. dec. Example 20,3,3-diethyl-9,11-neopentylene-6,7,6',7'- dibenzothiatetracarbocyanine iodide CH3 CHS \0/ Mc CII2 /S) C-CH=@ @-CH=CH-CH=CH-CH=c N 02HS I ethyl - 2 - (1,5,5 trimethylcyclohexonylidene)- methylnaphtho[2,llthiazolium iodide (2.39 g., I mol.), 50 anilinoacrolein anil hydrochloride (2.58 -., I mol. + 100%) and acetic anhydride (20 ml.) were mixed and heated under reflux for thirty minutes. The reaction mixture was chilled, filtered, and the solid was - suspended in ethyl alcohol (40 ml.). 1-ethyl-2-methylnaph55 tho[2,I]thiazolium iodide (1.8 g., 1 mol.) and - triethylamine (1.4 ml., 1 mol. + 100%) were added, and the reaction mixture refluxed for forty minutes. The reaction mixture was filtered hot, and the ffltrate chilled overnight. The crude dye (0.5 g., 13%) was filtered off, washed with a little methyl alcohol and dried. After 60 recrystalaation from ethyl alcohol, the yield of pure dye was 0.30 g. (8%), M. P. 201-2' C. dec. Example 21.-3,3'-diethyl-9,11-(2-methylti -iniethylene)- thiatetracarbocyanine iodide 65 H CEIS C H2c CH2 1 7 0 C-CH=C \Co@i @-CH=CH-CH=CH--CH=C N/"V I c2H5 I C2115 3 - ethyl - (1,5 - dimethyl - 3 - cyclohexenylidene)- 75 Example 22.-3,3'-diethyl-9,11-neopentyle ne-oxa-tricarbocyanine iodide CH3 CH3 \ 0/ 0- 0 H2C CH2 C-CH@cl @-CH=CH-CH=C/ \ C N H N/U I C 2H5 I c2HS 3 - ethyl - 2 - (1,5,5 - triraethyl - 3 - cyclohexe nylidene)methylbenzoxazolium iodide (0.41 g., I mol.), 2p-acetanilidovinyl-3-ethylbenzoxazol-lum iodide (0.43 g., I mol.), and triethylamine (0.28 ml., I mol. + 100%) were dissolved in ethyl alcohol (10 ml,) and heated under reflux for ten minutes. The reaction mixture was chilled and the crude dye tlirown out of solutio-@i by the addition with stirring of water (100 ml.) and ether (100 ml.). The water and ether solutions were decanted and the residue dissolved in methyl alcohol (10 ml.) and stirred with sodium iodide (2 g.). The crude crystalline dye was then filtered off and dried. After two recrystallizations from methyl alcohol, the yield of purified dye was 0.06 g. (10%). M. P. 193-5' C. dec. As shown in British Patent 625,907, sensitizing dyes can be obwned by condensing a compound selected from those represented by Formula I above with a compound
[8]2,734 9,00 i:5 selected from those represented by the foflowing ge@q@ eral formula: XIV. Xi wherein R4, Xl, n and Z each have the values given above,and R... represents an alkyl group, such as methyl, ethyl, etc., or an aryl group, such as phenyl-, tolyl, etc. The following examples describe the preppration of Similar carbocyanine dyes which contain a mesonaphthyl group. Such dyes are not contemplated by t@e British patent. Example 23.-3,3'-diethyl-9-(I-naphthyl)-thiacarbocyanine iodide s ly \ C-CII=C-CIEL=c C2H5 3 - ethyl - 2 (2 nAphthy.IpTopqnyl)benzothiazolium iodide (I mol., 0.76 g.), 3-ethyl2-ethylmercaptobenzothiazolium ethosulfate (Z mols., 1.16 g.) and triethylamine (2 mols., 0.5 cc.) were dlissolved in ethyl alcohol (10 ml.) and heated under reflux for fifteen minutes. The reaction mixture was theil chilled overnight, Mtered, and the crude dye washed with water and dried. After two recrystallizations from methyl alcohol, the yietd of purified dye was 0.52 g. (51%), M. P. 287288' C. dec. Anal@Calcd. for C3lH27IN2S2: 1, 20.52; Found: I, 20.5. Example 24.-3-etltyl-l'-metityl-9-(I-naphthy l)-thia-21cai-bocyanine iodide s C-Cll=C-Cll= U li3 c2HS I 3 - ethyl - 2 - (2 naphthylpropenyl) benzothiazolium iodide (I mol., 0.76 g,), 1-methyl-2- phenylmercaptoquinoliniuni iodide (1 mol. + 10%, 0.70 g.) and triethylamine (I mol. + 100%, 0.5 ml.) were dissolved in ethyl alcohol (10 ml.) and heated under reflux for fifteen minutes. The reaction mixture was c@illed ovemight, filtered, and the crude dye washed with water and ethyl alcohol and dried. After two recrystallizations from methyl alcohol, the yield of puriiied dye was 0.45 g. (45%), M. P. 246-247' C. dee. Anal.-Caled. for C32H27IN2S: 1, 21.20; Found: 1, 21.1. Exatnple 25.-l',3-diethyl-9-(I-naphthyl)-thi a-4'-carbocyanine iodide C-CH=(,.-CH C 2115 3 ethyl 2 - (2 naphthylpropenyl)benzothiazolium iodide (I mol., 0.76 g.), I-ethyl-4- phenylmercaptoquinclinium-p-telLienesulfonate (1_ mol. + 100%, 1.46 g.) and triethylamine (@l moi. + 1000/c@, 0.5 cc.) -1-6 w@rp dissolved in ethvl alcohol (10 ml.) and heated under reflux for fifteen minutes. 'Ihe reaction mixture was then chilled overni.-ht, ffitered, and the crude dye washed with water and dried. After two recrystallizations from methyl alcohol, the yield of purified dye was 0.50 g. (49%), M. P. 231-232' C. dee. The new dyes of my inventilon are useful in spectrally sensitizing photographic silver halide emulsions when incorporated therein. The dyes are especially useful for 10 extending the spectral sensitivity of the customardy einployed gelatino suver chloride, gelatino silver chlorobromide, gelatino silver bromide, gelatino silver bromiodide, and gelatino silver chlorobromiodide developingout emulsions. To prepare emulsions sensitized with one 15 or more of my new dyes, it is only necessary to disperse the dye or dyes in the emulsiqns. The methods of-incorporating dyes in emulsion are simple and are,known to those skuled in the art. In practice, it is convem'eiat to add the dyes to the emulsions 'M the form of a solu20 tion in an appropriate solvent. Pyridine or acetone has proved satisfactory as a solvent for most of my new dyes. The dyes are advalitageously incorporated in the finished, washed emulsions and should be uniformly distributed throughout the emulsions. 25 The concentration of the dyes in the emulsions can vary widely, e. g. from 5 to 100 mg. p r liter o P - f flowa.ble emulsion. The concentration of the dyes will vary according to the type of emulsio-n a'nd according to the effect desired. The suitable and most economical'co-n30 centration for any given emulsion will be apparent @to those skifled in the art, upon makin- the ordinary tests and observations customarily used in the art of emulsion making. To prepare a gel4tino-silver halide emulsion sensitized with one or more of my 4ew dyes, the follow35 ing procedure is satisfactoryA quantity of dye is dissolved in pyridine or acetone (or a mixture of acetone and pyridine) and a volume of this solution, which may be diluted with water, containing from 5 to 100 m.a. of dye, is slov@ly added to about IOOO 40 cc. of gelatino-silver halide eraulsion, with stirring. Stirring is continued until the dye is thoroughly dispersed in the emulsion. With most of my dyes, from 10 to 20 ma.. of dye per liter of gelatino-silver bromide or bromiodide emulsion 45 (containing about 40 g. of silver halide) suffices to produce the maximum sensitizing effect. With the finer grain emi,ilsions, somewhat larger concentration of dye may be needed, to produce the maximum sensitizing effect. The above statements are only .Ilustrative, as it wiU 50 be ppparent that the dyes can b,e incorporated in photogrkdhic emulsions by any of the other methods customarily employed in the art, e. g. by bathing a plate or film upon which an emulsion is coated in a solution,of the dye in an appropriate solvent. HoweVer, bathing methods are ordinarily not to be preferred. Emulsions sensitized with the dyes can be coated on suitable supports, such as glass, cellulose derivative film, resin film or paper in the usual manner. Photographic sflver halide emulsions, such as those 60 listed above, containing the sensitizing dyes of my inven tion can also contain such addenda as chemical sensitizers (e. g. sulfur sensitizers, such as allyl thiocarbamide, thiourea, allylisothiocyanate, eystine, etc.), vari65 ous gold compounds, such as pot'assium chloroaurate, auric trichloride, etc. (see U. S. Patents 2,540,085; 2,597,856; and 2,597,915, for example), various palladium compounds (such as palladium chloride (U. S. 2,540,086), potassium chloropalladate (U. S. 2,598,079), 70 etc.) etc., or mixtlires of such sensitizers, antifoggants (e. g. benzotriazole, nitrob@nzimidazole, 5-ilitroindazole, etc., (see Mees-"The Theory of the Photographic Process," Macmillaii pub., pg. 460), or mixtures thereof), hardeners (e. g. formaldehyde (U. S. 1,763,533), *ome 75 alum (U. S. 1,763,533), glyoxal (Ger. 538,713), dibrom-
[9]2,734,900 17 acrolein (Br. 406,750), etc.), color couplers, (e. g. such as those described in U. S. Patent 2,423,730, Spence and Carroll U. S. application 771,380, filed August 29, 1947, now U. S. Patent No. 2,640,776, issued June 2, 1953, etc.), or mixtures of such addenda. Dispersing agents for color couplers, such as substantially water-insoluble, 5 high boiling crystalloidal materials, such as those set forth in U. S. Patents 2,322,027 and 2,304,940, can also be employed in the above-described emulsions. What I claim as my invention and desire secured by 10
