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Publication numberUS3672906 A
Publication typeGrant
Publication dateJun 27, 1972
Filing dateMar 25, 1970
Priority dateJul 28, 1967
Also published asUS3715351
Publication numberUS 3672906 A, US 3672906A, US-A-3672906, US3672906 A, US3672906A
InventorsBrooker Leslie G S, Fumia Arthur Jr
Original AssigneeEastman Kodak Co
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Silver halide emulsions sensitized with methine dyes containing a cyclopentanone nucleus
US 3672906 A
Novel cyanine dyes containing a cyclopentanone nucleus in the methine chain are prepared by the acid hydrolysis of cyanine enamine derivatives. These cyanine dyes are spectral sensitizers for photographic silver halide emulsions. A number of the new dyes extend the sensitivity of photographic silver halide emulsions into the red and near infra-red regions of the spectrum.
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Description  (OCR text may contain errors)

United States Patent once 3,672,906 Patented June 27, 1972 ,67 ,90 SILVER HALIDE EMULSIONS SENSITIZED WITH METHINE DYES CONTAINING A CYCLO- PENTANONE NUCLEUS Leslie G. S. Brooker, Rochester, and Arthur Fumia, Jr.,

Hilton, N.Y.,-assignors to Eastman Kodak Company, Rochester, N. a

No Drawing. Continuation-impart of application Ser. No. 656,647, July 28, 1967. This application Mar. ,25, 1970,

Ser. No. 22,707 Int.'Cl. G03c 1/08 Us. or. 96-142 .7 s Claims ABSTRACT OF THE DISCLOSURE Novel methine dyes containing a cyclopentanone nu-' cleus in the methine chain are prepared by the acid hydrolysis of cyanine enamine derivatives. These methine dyes are spectral sensitizers for photographic silver halide emulsions. A number of the new dyes extend the sensitivity of photographic silver halide emulsions into the 2 red and near infra-red regions of the s'pectrum.

spectrally sensitized with a methine dye comprising a nitrogen-containing heterocyclic nucleus having from 5 to 6 atoms in the heterocyclic ring, said nucleus being of the type used in cyanine dyes, said heterocyclic nucleus being joined by a dimethine linkage to the 2-carbon atom of a cyclopentanone nucleus.

Especially useful dyes which sensitize photographic silver halide emulsions to infra-red radiation are those which comprise first and second nitrogen-containing heterocyclic nuclei containing from 5 to 6 atoms in the heterocyclic ring, said nuclei being of the type 'used in cyanine dyes, said first nucleus being joined by a di methine linkage to the Z-carbon atom of a cyclopentanone ring, and said second nucleus being joined by a dimethine linkage to the S-carbon atom of said cyclopentanone nucleus.

The preferred cyanine dyes of the invention are rep- I resented by the following general formulas:

This application is a continuation-impart of our copending U.S. application Ser. No. 656,647- filed July 28, 40

1967, now abandoned.

This invention relates to novel photographic materials, and more particularly to photographic silver halide emulsions spectrally sensitized with methine dyes.

We have now found that certain methine dyes are" excellent spectral sensitizers for bothblack and white and color photographic silver halide materials. 'A'-number of these new dyes extend the sensitivity of photo-' graphic silver halide emulsions into the red and near infra-red regions of the spectrum. 1 1

It is one object of this invention to provide light sensitive silver halide spectrally sensitized with methine dyes. Another object of this invention is to provide'photographic silver halide emulsions containing certain methine dyes. i

Other objects of this invention will become apparent from a consideration of the general'description and examples, and the appended claims. 1

In accordance with one embodiment of this invention, light sensitive photographic silver halide emulsions are H. om

wherein mtand n 'each represents a positive integer'of from to 2, and R and R each represents an alkyl group, preferably a lower alkyl containing from 1. to 4 carbon atoms, e.g., methyl, ethyl, propyl, isopropyl,

- group, e.g., phenyl, naphthyl, tolyl, chlorophenyl, sulfophenyl, carboxyphenyl, etc.; and, Z and Z each represents the nonmetallic atoms required to complete a 5- to 6-me1'nbered heterocyclic nucleus such as a thiazole nucleus (e.g., thiazole, methylthiazole, 4-phenylthiazole, 5-

EXAMPLE 1 2,5 -bis[ (3-ethyl-2- benzothiazolinylidene) ethylidene] cyclopentanone o I (i v C=CHQH=C/' \C,-OZHCH=C H2C--CH2 3,3-diethy l 10,12 ethylene ll (l-pyrrolidinyDthiatri carbo'cyanine iodide (6.4 g), 1 mol.), water (25 ml. and 36% hydrochloric acid (2 m1.)"are mixed and heated under reflux with stirring. The mixture was diluted several times with additional acid and water, with refluxing, continued until the absorption of the starting material had disappeared. After chilling, the solid is collected on a funnel, washed withacetone and dried. After two ref crystallizations from pyridine/methanol, the yield of purified dye is 2.1 g. (46%) MP. 246-247 C. decomposes.

In place of the 3,3'-diethyl-10,12-ethylene-ll-(l-pyrrolidinyl) thiacarbocyanine iodide in the above example, there can be substituted an equivalent amount of, for example, 331 dit-hyl-IOJZ-ethylene-ll-(l-pyrrolidinyl) oxatricarbocyanine salt such as the chloride, bromide, iodide, etc. or a 3,3'-diethyl-10,12-ethylene-ll-(l-pyrrolidinyl) selenotricarbocyanine salt or "a 3,3'diethyl-10,12- ethylene ll-(1-pyrrolidinyl)thiazolotricarbocyanine salt, and the' likeyto give the corresponding cyanine dyes of the invention having generally similar spectral sensitizing properties when incorporated in photographic silver halide emulsions.

' EXAMPLE 2 I 2,5-bis l-ethylnaphtho[11,2-d]thiazolin-2 ylidene) 7 1 ethylidene]cyclopentanone' 3,3-diethyl 10,12 ethylene-11 (1-pyrrolidinyl)-'4,5,4',5- dibenzothiatricarbocyanine p-toluenesulfonate (3.9 g., 1 mol.), water (75 ml.) ethanol (200 ml.) and 36% hydro'chloric acid (5 ml.) 'are heated under reflux withstir: ring. The mixture is diluted several times with'additional for example, 3-ethyl-2-{2-,[2-(l-pyrrolidinyl)cyclopentyl] EXAMPLE 3 -2',5-bis[-(1,3;3 trimethyl-2 indolinylidene)-' ethylidene]cyclopentanone EXAMPLE 4 .2- [(3ethyl-Z-benzothiazolinylidene)ethylidene] cyclopentanone N Hz 3 ethyl-2% 2-[2-(l-pyrrolidinyl)cyclopentenyl] vinyl benzothi-azolium iodide (6.0g. 1 .mol.) is treated with water and 36% hydrochloric acid in the manner as Example 2. After two recrystallization from .l yridine/ methanol, the yield of purified dye is 1.1 g. (31%), MP.

230-231 C. dec.

lnplace of the 3 -ethyl-2-{2-[Z-U-pyrrolidinybcyclopentyl]v1nyl}benzothrazolium iodide in the above exam ple, there can be substituted an equivalent ainountof:

viny1}benzoxazolium salt such as the bromide, chloride, iodide,'etc., [or the corresponding selenazolium salts, or the cor'responding thiazoliurn salts, and theflike,to give the corresponding cyanine dyes of the invention thatlike- Wise extend the sensitivity of photographic silver halide emulsion, at the concentrations indicated in the following Table 1. The dyes are exposed to a minimum amount of sensitized silver halide emulsions is employed. After digestion at, 50-52 C. for about ,10 minutes, the emulsions acid and water with refluxing continued until .the'absorp tion of the startnig material has disappeared. After chilling, the solid is' collected on "a funnel, washed with metha' nol and dried. Atfter two recrystallizations from pyridine/ methanol, theyield of purified dye is 0.9 g. (32% -MLP. 275-276 C. dec. v, V p In 'place of thel3,3'-diethyl-l0,12 ethylene- (l-pyrrol idinyl) 4,5,4',5 'dibenzothiacarbocyanine p-toluenesulfonate in ,the above example there can be substituted an equivalent amount of, for example, 3,3-diethyll0,l2-' ethylene-(l-pyrrolidinyl) 4,5,4',5' dibenzoxatricarbocyaninesaltsuch as the chloride, bromide iodide, etc, to give thecorres p'ondin'g cyanine dye of'the invention hav ing generally similar spectral'sensit-izing properties for photographic silver halide emulsions.

are coated at a coverage of 459 mg. of silver and 1040 mg. of gelatin per square foot on a cellulose'acetate film support. A sample of each coating is exposed on an Eastman? 13 sensitometer and to a wedge spectrograph, proc essed for 5 minutes in Kodak DK-SO developer (Handbook of Chemistry and Physics, 30th edition, 1947, Chemical Rubber Publishing Co., Cleveland, Ohio, page 2558) having the following composition:

G. N-methyl-p-aminophenol sulfate 2.5 Sodium sulfite (desiccated) 30.0 Hydroquinone v E 2.5 Sodium metaborate 10.0

Potassium bromide -2-.. 0.5

Water to make 1.0 liter.

and then fixed in a conventional sodium thiosulfate fixing bath, washed and dried. The sensitizing values obtained are shown in the following Table l. p

I TABLE 1 Dye and i f Dye of eoneentra- Sensitization (m Examtion .I V v ple No. mole silver Emulsion type Range 7 Maximum 0. 103 Silver chlorobromide 760 to 810. 790

0.13 do-.- 500 to 705.

1 No definite maximum.

The following examples illustrate the preparation of the intermediate dye compounds employed in the procedures of above Examples 1 to 4 to prepare the cyanine dyes of the invention. As indicated previously, additional details for the preparation of these and related dye intermediates can be had by reference to the aforementionedR. A. Jetfreys copending application, Ser. No. 518,010, filed Jan. 3, 1966.

EXAMPLE 3,3-diethyl-10,12-ethylene-1l-(l-pyrrolidinyl) thiatricarbocyanine iodide N-cyclopentenylpyrrolidine (0.7 gram), 2-[2-ac'etanilidovinyl] 3 ethylbenzothiaziolium iodide (4.5]grams) and sodium acetate (0.8 gram) in acetic anhydride (25 ml.) are refluxed together for hour, and the resulting blue solution is chilled to precipitate the dyeproduct formed. The, dye product isrfiltered off, washed with ethanoLandwater; and recrystallized from methanol "as moss green-needles, M.P. above345 C., in 1 gram (31%) yield; 4 EXAMPLE-6 Y l 3,3'-- diethyl 10,1 2- ethylene -11 (1 pyrrolidin'yl)- 2 (2- anilinovinyl) l ethyl-naphtho[1,2- d] thiaz'oli um p-toluenesulfonate' (21 g;, 2 mols. +5%')', N-cyc1opentenylpyrrolidine 2.7 g.', '1" mol'.),- triethylenediainine (7.4 3., 2 mols; and acetic anhydride (317 ml., 2 rhols.) are dissolved in N,N-dimethylacetanjide (40 m1.) and heated on a steam bath, with stirringp-forone-half hour. After chilling, the crude product is collected ona filter,v washed with methanol and dried. Attertwo re.- crystallizations from methanol, the yield oftpu'rified dye is 6.1 g. (39%), M.P. 253-254 C. dec.

tdibenzothiatricarbocyanine p-toluenesul- .e 50

v of those prepared withflh'ydrophilic colloids EXAMPLE 7 10,12 ethylene-1,l,3,3,3T,3'hexamethyl-1.1-( l-pyrrolidinyDindOtricarbQcyanine iodide N-cyclopentenylpyrrolidine1267; grams) and 2-[2- acetanilidovinyl] 3 ethylbenzothiazolium iodide (9 grams) in ethanol (25 ml.) are shaken togetherat room temperature for hour. 1 Thev dye product formed is filtered otf and recrystallized from ethanol to remove magenta and blue impurities. The orange dye is obtained as maroon leaflets, M.P. 297-299 C. with decomp.

(darkens at 290 c. in 2.1; grams (23%) yield. A

v N-cyclopentenylpyrrolidine I mo-cn. E 1 5, 7 H1 H: I I y N 5 Hr0 0,Hp

v H *-CHz This compound isprepared in the mariner described 1.5, by GIStark, et aha]. Am. Chem.jSoo., 85,' 216G963);

For the. preparation of photographic emulsions," this new dyesof the inventionare advantageously incorporated in the finished silver halide emulsion and shouldfdjf course be uniformly distributed'throughout the emulsion;

. Themethod of incorporating dyes in emulsions are "relai tively simple and well known to those skilled in the art of emulsion making. For example, itis convenient to addthe dyes from solutions in appropriate solvents; in. which the,solvent selected should have "no deleter ioiis effect on the ultimate light-sensitive materials; Methanol,

isopropanolal yridine etc. alone orin eombinat'iorrhave proven satisfactory as solvents for the majority of the new dyes of the invention. The type of silver halide emu1 sions that are sensitized with the new dyesinclu'de any atl e known to be satisfactory for dispersing light-sensitive 9 silver halides, for examples, emulsions prepared with hydrophilic colloids, such as natural materials, e.g., gelatin, albumin, agar-agar, gum arabic, alginicacid, etc., and synthetic hydrophilic resins, e.g., polyvinyl alcohol, poly- 10 chloroplatinate (Trivelli et al. US. Pat. 2,566,245, issued Aug. 28, 1951), ammonium chloroplatinite (Trivelli et al. US. Pat. 2,566,263, issued Aug. 28, 1951), benzotriazole, nitrobenzimidazole, S-nitroi'ndazole, benzidine, mercapvinyl pyrrolidone, cellulose ethers, partially hydrolyzed tans, etc. (see MeesTh e.Theory of the Photographic cellulose acetate, etc. Process, MacMillian Pub., 1942, page 460), or mixtures The concentration of'the new dyes in' the emulsions can thereof; hardeners, such as formaldehyde (Miller US. Pat. be widely varied, i.e., generally from about 5 to about 1,763,533, issued June 10, 1930), chrome alum (1,763,- 100 mg. per liter of flowable emulsion-The specific con- 533), glyoxal (Brunken US. Pat. 1,870,354, issued Aug. centration will vary according to the type of light-sensitive 9, 1932), dibromacrolein (Block et al. British Pat. 406,- material in the emulsion and according to the effects de- 750, accepted Mar. 8, 1934), etc.; color couplers, such as sired. The most advantageousdye concentration for any those described in Salminen et al. US. Pat. 2,423,730, given emulsion can be readily determined by making the issued July 7, 1947, Spence and Carroll US. Pat. 2,640,- tests and observations customarily used inthe art of 776, issued June 2, 1953, etc.; or mixture of such addenda. emulsion making. The emulsions are coated to advantage Dispersing agents for color couplers, such as those set on any of the support materials commonly used for phoforth in Jelley et al. US. Pat. 2,322,027, issued June 15, tographic elements, for example, paper, glass, cellulose de- 1943, and Mannes et al. US. Pat. 2,304,940, issued Dec. rivatives, such as cellulose acetate, cellulose acetate-pro- 15, 1942, can also be employed in the above-described pionate, cellulose nitrate, etc., synthetic resins, such as emulsions. poly styrene, polyethylene terephthalate and other poly- The invention has been described in detail with particuesters, polyamides, such as nylon, and the like. lar reference to preferred embodiments thereof but it will To prepare a gelatino-silver halideemulsion desens ibe understood that variations and modifications can be tized with one of the new dyes, thefollowing procedure is effected within the spirit and scope of the invention as desatisfactory: A quantity of dye is dissolved in a suitable scribed hereinabove and as defined in the appended solvent, and a volume of this solution containing the declaims. r sired amount of dye is slowly added with intimate mix- We claim; ing to about 1,000 cc. of light-sensitive gelatino-silver ha- 1. A light-sensitive photographic silver halide emulsion lide emulsion. With most of the new dyes, from about spectrally sensitized with a methine dye comprising a 10 to 20 mg, of dye per liter of emulsion suffices to proheterocyclic nucleus selected from the group consisting duce the desired sensitizing effect with the ordinary gelaof a thiazole nucleus, abenzothiazole nucleus, a naphtino-silver' halides including silver chloride, bromide, thothia'zole nucleus, a thianaphtheno-7',6',4,S-thiazole nubromoiodide, chlorobromide, chlorobromoiodide, etc., cleus, an oxazole nucleus, a benzoxazole nucleus, a naphthemulsions. With fine-grain emulsions which include most oxazole nucleus, a selenazole nucleus, a benzoselenazole of the ordinary employed gelatino-silver chloride emulnucleus, a naphthoselenazole nucleus, a thiazoline nusions, somewhat larger concentrations of dye may be cleus, a Z-quinoline nucleus, a 4-quinoline nucleus, a 1- necessary to secure optimum sensitizing effect. While the isoquinoline nucleus, a 3-isoqinoline nucleus, a 3,3-dialkylpreceding has dealt with emulsions comprising gelatin, it indolenine nucleus, 21 pyridine nucleus, an imidazole nu-' will be understood that these remarks apply generally to cleus', a benzimidazole nucleus and a naphthimidazole n11- any emulsions in which a part or all of the gelatin is subcleus; said heterocyclic nucleus being joined by a distituted by another suitable hydrophilic colloid such as 40 methine linkage to the Z-carbon atom of a cyclopentanone' those previously mentioned. nucleus. 8 The above statements are only illustrative and are'not 2. A light-sensitive photographic silver halide emulsion to be understood as limiting the invention in any sense,-as spectrally sensitized with a cyanine dye comprising first it will be apparent that the new dyes can be incorporated and second nitogen-containing heterocyclic nuclei seby other methods in many of the emulsions customarily lected r m the group consisting of a thiazole nucleus, a used in the art. For instance, in a less preferred method, benzothiazole nucleus, an naphthethiazole nucleus, a thiathe dyes can be incorporated by bathing a plate orfilm. naphtheno-7',6,4,5-thiazole nucleus, an .oxazole-nucleus, bearing an emulsion, in a solution of the dye. a benzoxazole nucleus, a naphthoxazole nucleus, a selen- Ph'otogfaphic Silver halide e lsions, Such as those azole nucleus, at benzoselenazole nucleus, a napththoselenlisted abOVe, containing the Sensitilillg y 0f t azole nucleus, a thiazoline nucleus, a 2-quinoline nucleus, tion can also contam K addenda as chqmwal 9 a 4-quinoline nucleus, a l-isoquinoline nucleus, a 3-isotizers, e.g., sulfur sens1tizers (e.g., allyl thlocarbamide, quinoline nucleus, a 33 dialkyfindolenine nucleus, a thiourea, allyhsothiocyanate, cystme, etc.), var1ous gold idine nucleus, an imidazole nucleus, a benzimidazole cpmpounds pota.ssmm chloroaurate aunc i cleus and a naphthimidazole nucleus; said first heteroetc) (see Baldslefen 2540385 i 55 cyclic nucleus being joined by a dimethine linkage to the Feb. 6, 1951; Damschroder US. Pat. 2,597,856, issued b t f I t l d May 27, 1952 and Yutzy et al. US. Pat. 2,597,915, issued a a 8 i t i May 27, 1952), various palladium compounds such as 7 0nd heterocycllc nucleus belng omed by a dlmethlnehnkpalladium chloride (Baldsiefen US. Pat. 2,540,086, issued age to f PP atom of Sald cyc lopentan one q Feb. 6, 1951), potassium chloropalladate (Stauffer' et al.. A h senltlve'p hotographl sllver hahd? emulsion US. Pat. 2,598,079, issued May 27, 1952 etc., or mixsp y sensitlzed Wlth a methme dye havms one of tures of such sensitizers; antifoggants, such as ammonium t following formulas:

0 t I, -Z R-N(CH=CH)n -i*C=CHCH=(IJ CIJHQ H2C'-UH2 and 0 ll --z-. 0 Z1....- 1 RMN (-CH=CH) n -C=CH-CH=C C=CHCH=C CH GH)m-I' N' RI ,l 11 a. wherein m and n each represents a positive" integer of from 1 to 2; R and R each represents a member selected from the group consisting of an alkyl group, an allyl group, and an aryl group; and, Z and Z each represents the non-metallic atoms necessary to complete a heterocy- 5 and'an y p; and Z and 1 h P PFI #1 9 Clic 1111016118 Selected 1116 group consisting of a thiaf metallic atoms necessary to complete a heterocyclic nu zole nucleus, a benzothiazole nucleus, a naphthothiazole imc e s, a thianaphtheno 7,I6,I45 thiazole nu an celus selected, frorn the group .conslstmg of a thlazole oxazole nucleus, a benzoxazole nucleus, a naphthoxazole I I s a benzothlazole naphthothlazole I nucleus, at selenazole nucleus, at benzoselenazole nucleus, 10 e eu S, a thiauaphthenoJ';Q',4,-th1azo1enucleus, an oxa- Pl i I 1 1 4 l in thlilolmfi i l f' far zole nucleus, henzokazole nucleus, a, naphthoxaz ole qumo e nuc eus, a -qumo e nuc eus, a -1s oqu1no me I I p nucleus, a 3-isoquinoline nucleus, at 3,3-dialkylindolenine P a Selenazole nIucleusf a f f p nucleus nucleus, a pyridine nucleus, an imidazole nucleus, at benz-J. I E 'naphtmselenalole 131919115, flnaolflw 111191595, 3 i-midazole nucleus and a naphthimidazole nucleus, 7 l5 quinoline nucleus, at 4-quinoline nucleus, a lisoquino'line A light R Rhotographl c silver l Fmulslon nucleus, a 3-isoquinoline nucleus, a 3,3-dialkylindolenine spectrally sensitized with a methlne dye hav ngthev foll lowing formula: H h I I nucleus, a pyridlne nuc eus, an lmid a-zole nucleus,'abenzo I II 1. I imidazole nucleus anda naphthimidazole'nucleus, I

ll I 6. A light 'sensitive'Iphotographic silverfhalide emulsion CH=CH)II I (-J=C CH: I spectrally sensitized with a cyanine. dye selected from v the 'group consistingof- 1 i Ha .Ha v I I ."-f wherein n represents a positive integer of from 1 $12; 2,5-bis[(3-ethyl-2-benuothiazolinylidene)eth fi j R represents a member selected from the group consisting cyclopentanong, t I II I I of a alkyl g p allyl g p and an al'yl 8MP; 2,5-bis[(1-ethylnaphtho[.1,2-d]thiazolin-2-ylidene) 1 Z represents the non-metallic atoms necessary to complete I I ,I I I a heterocyclic nucleus selected from the group consisting I ethylldenelcxclopemanons, I Y of a thiaz ole nucleus, at benzothiazole nucleus, a naph- 2,5-bis[(1,3,3-trimethyl-2-indolinylidene)ethylidene] thothiazole nucleus, a thianaphtheno-7',6',4,5-thiazole I cyclopemanone and I nucleus, an oxazole nucleus, a benzoxazole nucleus, at 2 3 h 12b d naphthoxazole nucleus, a selenazole nucleus, an benz o- I l T enzo m Y P y g II selenazole nucleus, a naphthoselenazole nucleus, a thiazpen anon I I oline nucleus, a Z-quinoline nucleus, a 4quin0line nucleus, I K a msoquinoline nucleus, a 3.,isoquino1ine nucleus, 3 7. A l ght sensitive photographic silver halide emulsion dialkylindolenin e nucleus, 9. pyridine nucleus, an imidazole spectrally sensitized with 2,5-bis[(3-ethyl-2 henzothiaz a benzimidazole nucleus and a naphthlmidazole olinylidem)Iethylidene]cyclopentanoneI I I I I I 5. A light sensitive photographic silver halide emulsion 40 A'hght i l fl ifi silver fi m spectrally, sensitized with a dye having the following t l Sensltlzed h fifin ld formula:- I Y 7 i l linylidene)ethylidene]cyclopentanone. I l

" k v l 0 a v r A r a Y R1 l(-C =cH)l.-1- J=0u-cn=o c=cH-cn=(-c1r=cH m-1-$I-m 5 7 References .Cited I UNITED STATES PATENTS I 2,860,984 11/1958 Jones 96-140 3,140,182 ,7/1964 Haseltine et a1. 96--l41 3,148,065 9/1964 Craig et a1. 96-140 FOREIGN PA TENTS 595,785 12/1947 Great Britain.

l 12 A, wherein m and n represents a positive integer of from t to 2; R and R each represents am'einber selected frorriI the group consisting of an alkyl group, an allyl group,

J. TRAVIS BROWN, Primary Examiner us. 01. X.R.

Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US4917977 *Dec 23, 1988Apr 17, 1990E. I. Du Pont De Nemours And CompanyMethine dye, ethylenically unsaturated compound and free radical generators
US4933269 *Nov 27, 1989Jun 12, 1990Eastman Kodak CompanyPhotographic silver halide element containing infrared filter dyes
EP0403933A1 *Jun 12, 1990Dec 27, 1990Eastman Kodak CompanyInfrared absorbing trinuclear cyanine dyes for dye-donor element used in laser-induced thermal dye transfer
U.S. Classification430/593, 430/594, 548/455, 548/400, 548/156, 548/180, 548/152, 548/150
International ClassificationG03C1/12, C09B23/01, C09B23/00, C09B23/10
Cooperative ClassificationC09B23/105, G03C1/12, C09B23/0066
European ClassificationG03C1/12, C09B23/00D, C09B23/10B