US2066968A

US2066968A - Manufacture of light-sensitive materials

Info

Publication number: US2066968A
Application number: US660287A
Authority: US
Inventors: Dieterle Walter; Zeh Walter; Zerweck Werner
Original assignee: Agfa Ansco Corp
Current assignee: GAF Chemicals Corp
Priority date: 1931-03-27
Filing date: 1933-03-10
Publication date: 1937-01-05
Anticipated expiration: 1954-01-05

Description

Jan. 5, 1937. w. DIETr-:RLE Er AL 2,066,958

I MANUFACTURE OF LIGHT SENSITIVE MATERIALS i Filed March 1o, 195s ily? FERC/1.403675 Eg 3 I l/l/- Patented Jan. 5, 1937 UNITED STATES PATENT GFFICE l MANUFACTURE 0F LIGHT-SENSITIVE MATERIAL Walter Dieterle and Walter Zeh, Dessau in Anhalt, and Werner Zerweck, Frankfort-amtlic- Main-Fechenheim, Germany, assignors to Agfa Ansco Corporation, Binghamton, N. Y., a corporation o! New York Application March 10, 1933, Serial No. 660,287 In Germany March 27, 1931 5 Claims.

(the quiuoline nucleus being linked in 2 or 4position) Y=S, Se Y=S, Se, C(CH3)2,O R W=H. N( alkyl, alkoxyl,

Rl r and r=alkyl R=H, alkyl, aryl, ac R'=H, alkyl n=O or 1 X=halide, perchlorate, alkylosulfate, paratoluene sulfonate, nitrate, or another suitable anion, are particularly suited for sensitizing photographic emulsions. The dyes are characterized by their sensitizing eiiiciency and their stability against agents used for stabilizing the emulsions, for instance, potassium bromide.

In the appended claims the expression an amino group is to be understood as including not only the amino group but also substituted amino groups.

The amino group having the radicals R. and R may be introduced at any positionof the nuclei, the 5 and 6 positions are preferred for the nuclei of the kind of the benzthiazole nucleus; in the case of the qunoline nucleus the 6 and 'l positions are preferred. There may further be present in the nuclei monovalent radicals, e. g. alkyl, alkoxyl, halide in any possible position.

(ci. ssa-7) The unsymmetrical character o! the dyes may have various causes. For instance, Y may diner from Y', or if Y and Y' represent the same radical, W may be different from the group for instance, H; or ii Y and-Y' represent the same radical and W represents the two /a N\ groups may be linked in different positions. These possibilities are o; course only a few o! those which are includedf'within this invention.

The general Formula 1 comprises three principal groups of cyanines dyes:

Trimethinecyanines of the Formula 2,

4 Y (the qulnollne W 3 ne hema 2 A 2 linked in 2 or a 1 4poe1tlon) N N l r' pseudocyanlnes of the Formula 3,

R Y 4 \N 1 H R/ ajo 2 l and isocyanines of the Formula 4.

may represent H; or alkyl, for instance, methyl or ethyl; or aryl, for instance, phenyl, naphthyl; or a substituted aryl;y or acyl, for instance, benzoyl, acetyl, propionyl or butyryl. R may be alkyl in the case of R being alkyl or aryl, or R is hydrogen in the case of R being hydrogen or acyl. X may represent any suitable anion that will precipitate the dye, for instance, a halide, perchlorate, alkylosulfate, paratoluene sulfonate, nitrate. r and r represent alkyl, for' instance, methyl, ethyl, propyl, butyl, amyl and th isomers of propyl butyl and amyl. W may be H; or

or alkyl, for instance, methyl or ethyl; or alkoxyl, for instance, methoxy or ethoxy.

The benzthiazole nucleus or the benzselenazole nucleus may contain besides the amino group one or several alkyl groups, such as methyl or ethyl groups, or alkoxyl groups, such as methoxy or ethoxy groups, or both alkyl and alkoxyl groups.

The introduction of the amino group into the benzthiazole nucleus causes a displacement of the range of sensitivity of the dyes towards the region of longer waves. For instance, the introduction of one diethylamino group into the benzthiazole nucleus of an unsymmetrical trimethinecyanine corresponding with the Formula 2 effects a displacement of the maximum of sensitization of about 30ML towards longer waves and when introduced into a benzselenazole nucleus one diethylamino group effects a displacement of the maximum of sensitization of about 28ML.

As seen there is a slight difference between the replacement of hydrogen in the benzene nucleus by a substituted amino amino group in the molecule of the thiocyanines and the selenocyanines. It is to be understood that the foregoing statement is given only by way of example. Other radicals which have already been mentioned may represent R and R. The replacement of 1 and r by different radicals is of minor elciency for displacing the range of sensitlvity. The radicals representing X are of no inuence in the purpose set forth. The influence on the displacement of the sensitization maximum and on the intensity of the sensitivity can easily be determined by a few comparative experiments.

In Figs. 1 to 3 of the accompanying drawing there are shown spectrograms of emulsions sensitized in accordance with the invention.

Fig. 1 shows the spectrogram of a silver halide emulsion sensitized with 1.l'diethyl5diethyl amino benzthio-benzselenocarbocyanine iodide,

Fig. 2 shows the spectrogram of a silver halide emulsion sensitized with 1.1'diethyl6.5'bis diethylamino-benzthiocarbocyanine perchlorate, and

Fig. 3 shows the spectrogram of a silver halide emulsion sensitized with 1.1diethyl6diethyl amino-5-ethoxy-benzthiocarbccyanine perchlorate.

The dyes are obtainable according to the desired solubility in form of the bromide, iodide, perchlorate etc. and are used in a quantity as usual for the known sensitizing dyes. tity amounts to 8 to 25 milligrams per 1 kg. of

emulsion ready for being cast which containsabout 9 per cent of gelatin, 4.5 per cent of silverhalide, the rest being water. We do not wish to limit our invention exactly to the quantities just This quani indicated, the most suitable amount will be found in each particular case by a few simple experiments. 'Ihe dyes may be added to the emulsion in form of solutions. Suitable solvents are the alcohols, for instance, methyl or ethyl alcohol, which may be used anhydrous or diluted with water. The dyes may be added to the emulsion during any stage of its production, however, they are preferably added to the nished emulsion bei'ore being cast. 'I'he dyes may likewise be added by coating the emulsion with them or by bathing the ilnished photographic materials in a bath in which the dye is dissolved.

'I'he production of the 4, 5, 6, or 7amino substituted 2-methyl-benzthlazoles serving as a starting material for preparing the dyes is described in Examples 1 to 9. Other bases than those described in these examples may be produced in an analogous manner. The method of preparing our new dyes from the bases is analogous to known methods and illustrate'd in Examples 10 to 20.

'Example 1.The preparation of 2-methyl-6- amino-benzo-thiazole corresponding with the formula is described in U. S. Patent 1,758,385 and reference is made thereto.

Example 2.-'1'he base 2methyl5amino benzthiazole corresponding with the formula can be obtained in two Ways.

. According to the rst way we proceed as follows: 2amino 4 acetylamino-toluol corresponding with the formula \COCH| is first rhodanatedI with NH4 SCN and Br in its methyl-alcoholic solution in the manner described in U. S. Patent 1,787,315 and then with anaqueous ammoniacal solution. 'I'he formed I5 spaanse product, probably the 2.5-diamino-6-methylbenzthiaaole corresponding with the formula The zinc mercaptide of this compound is transformed into the 2.6-dimethyl-5-acetylaminobenzthiazole with a melting point of about 178 C. corresponding with the above formula by'heating the aforesaid mercaptide with acetic anhydride.

According to the second way 3-chloro-4- acetylamino-6-nitrotoluene having a melting point oi 143 C. is transformed into 2.6-dimethyl- 5-nitro-benzthiazole forming compact, colorless crystals when crystallized from alcohol which melt at about 106 C. This compoimd yields the 2.6 -dimethyl-5-amino-benzthiazole when reduced with iron and acetic acid, forming colorless crystals which melt at about 143 C. 'Ihe thiazole can be easily acetylated.

Example 4.-The base 2.4-dimethyl-6-aminobenzthiazole corresponding with the formula HaN ,e 7

4 I13%-CHI is obtained as follows. Acetyl-toluylene-diamine corresponding with the formula NH: H

inc-oc/ is by means of SnClz transformed into the4 thiazthionium-compound in the manner described in U. S. Patent 1,637,023. pound with a solution of caustic alkali according to U. S. Patent 1,243,710 the corresponding o-amino-mercaptane corresponding with the` formula C Hz When treating this c0111-,v

2.4-dimethyl-G-amino-benzthazole which forms colorless crystals melting at about 118 C.

Example 5.-The base 2.4.6-trimethyl-7-ami-- no-benz-thiazole corresponding Awith the formula HaC- 6 7 5 2i 4 3/ CH;

is obtainable as follows. Amino-acetylaminoxylidin corresponding with the formula' CHI BaN-

benzthiazole corresponding with the formula mc s l 2 Isl/om,

and melting at about 285 C. is obtained. By boiling this compound with a strong aqueous solution of caustic alkali according to U. S. Patent 1,788,297 it is split up 'to the corresponding o-amino-mercaptane, which may be separated from the reaction mixture in form of the zinc mercaptide. By heating with acetic anhydride the 2.4.6-trimethyl- 7 acetylarnino-benzthiazole is obtainable. After recrystallization from its alcoholic solution this compound forms colorless crystals melting at about 208 C. By saponification with hydrochloric acid the 2.4.6-trimethyl- 7-amino-benzthiazo1e isv obtainable in form of colorless crystals melting at about 128 C.

Example iL-The base 2methy16dimethylam ino-benzthiazole corresponding with ythe formula 4H* Is-CB.

has already been described: cf. Bernthsen, Ann. 251, `page 29.

Example 7.--The base 2-methyl-6-diethyl-amino-benztliiazole corresponding with the formula ai om is obtainable analogously to the preparation of 'the dimethyl compound (cfrY Example 1).'Ifhe' chloride iormingnoolorless crystals is easily soluble in water and'decomposes when heated to a temperature of about 160 C. under strong evolution of gas. 1f the lbase is set free from. the chloride by means of an-aqueous solution of caustic alkali it separates in form' of a yellow oil which solidies when cooling.

Example 8.l-The base 2-methyl-5-dimethylamino-benzthiazole corresponding With the formula I6 i (cnam-54 1%;41113 amino-benzthiazole corresponding with the formula N-6 s 1 HC 2 1% fCHa is obtainable by heating 2-amino-3-methyl-5- phenylamino-thiophenol-zinc (cf. U. S. Patent 1,566,384) with acetic anhydridc. After crystallizing the compound from benzene it forms colorless crystals Which melt at about 138 C. and are easily soluble in benzene, alcohol and glacial acetic acid.

Example 10.-For .producing the dye [3-ethyl- 5 diethylamino benzthiazole (2) [3ethy16 ethoxy benzthiazole(2),] -trlmethine cyanineperchlorate corresponding with the formula s 7 6 oClHs Cgi 010| we proceed as follows:

A. 9 grams of 5-diethylamino-Z-methyl-benzthiazole ethyl-iodide and 6.5 grams of diphenylformamidine are intimately mixed; to this mixturc 25 cc. of acetic anhydride are added and the whole is boiled for 3A hour under reflux (about 140 C.). After cooling the reaction mixture ether is added drop by drop while stirring the mixture and rubbing the walls of the vessel. This procedure is continued until the formation of crystals occurs at the walls of the vessel. Now, the dye is precipitated by cooling the reaction mixture with a freezing mixture and filtered off. The intermediate product which melts in its pure state at 218 to 219 C. corresponds probably with the formula B. 4 grams of the intermediate product arel boiled with 2 grams of 2-methy1-6-ethoxy-benzthiazole-ethyl-iodide and 20 cc. of pyridine for 1%; hour under reiiux (about 125 to 130 C. The dye is then precipitated by addition of a few cc. of an aqueous solution of potassium iodide of l0 per cent strength and water, separated by filtration, dissolved in alcohol and precipitated from its alcoholic solution in form of its perchlorate by addition of a few cc. of an aqueous solution of sodium perchlorate of 1 per cent strength and water.

After recrystallization of the dye, its alcoholic solution shows an absorption maximum at a wave length of about 600ml.

Incorporated in a gelatino-silver-bromide emulsion containing about 4 per cent of silver iodide the dye imparts to it a range of sensitivity from about 500ML to about '725ml with a maximum at about 625ml.

Example 11.-For producing the dye [3-ethyl- S-diethylamino benzthiazole( 2 )l 3 ethylbenzthiazole- (2) ]-trimethinecyanine-perchlorate corresponding with the formula 4 grams of the intermediate product obtainable ethyl-iodide and diphenyl-formamidine in the manner described in Example 10 sub A, are boiled with 2 grams of 2-methyl-benzthiazole-ethyliodide and cc. of pyridine for 3A hour under reflux (125 to 130 C.). The reaction mixture is worked up in the manner indicated in Example 10.

The dye shows in its alcoholic solution an absorption maximum at a wave length of about 595ML. v

Incorporated in a gelatino-silver-bromide emulsion containing about 4 per cent of silver iodide the dye imparts to it a range of sensitivity from about 510ml to about 720ML with a maximum at about G/m.

Example 12.-The dye [3-ethyl-6-diethylamino-benzthiazole-(Z) 3 ethyl-benzelenazole- (2) l trimethinecyanine-iodide corresponding with the formula is produced in the same manner as described in the foregoing examples by starting from the corresponding materials.

The dye shows in its alcoholic solution an absorption maximum at a wave length of about 600ML.

Incorporated in a gelatino-silver-bromide emulsion containing about 4 per cent of silveriodide the dye imparts to it a range of sensitivity from about 510ml to about 715W with a maximum at about 630ml.

Example 13.-The dye [3-ethyl-5-diethylaminobenzthiazole(2)l [3-ethyl-6-diethylamino- Aso ' benzthiazole- (2) l-trimethinecyanine-perchlorate corresponding with the formula may be produced by mixing 1.5 grams of the intermediate product described in Example 10 with 2.3 grams of G-diethylamino-Z-methylbenzothiazole-ethyl-iodide and 15 cc. of pyridine, boiling this mixture for 3A hour under reflux and working up the reaction mixture as indicated in Example 10. The dye may likewise be obtained as iodide.

The alcoholic solution of the dye has an `absorption maximum at a wave length of about 625ML.

Incorporated in a gelatino-silver-bromide emulsion containing about 4 per cent of silver iodide the dye imparts to it a range of sensitivity from about 510W. to about 730ML with a maximum at about 655ML. Example 14,-For producing [3-ethyl-5-diethylamino benzthiazole (2)] [1-ethyl quinoline- (2) -trimethinecyanine iodide corresponding with the formula /7\ S /4\ 5 1 n H nl 2 2 1 (einem 4 a/ t1-t I? s I/HB\I 02H5 5 grams of the intermediate product obtainable from -diethylamino -2 methylbenzthiazoleethyl-iodide and diphenyl-formamidine as described in Example 10, are boiled for 2% hours with 4 grams of quinaldine-ethyl-iodide and 15 cc. of pyridine under reflux. The dye which forms is precipitated by addition of a few cc. of an aqueous solution-of potassium iodide of per cent strength and water and is recrystallized from alcohol.

The alcoholic solution of the dye has an absorption maximum at a wave lengthy of about 615m.

Incorporated in a gelatino-silver-bromide emulsion containing about 4 per cent of silver iodide the dye imparts to it a range of sensitiveness from about 515W. to about 730ml. with a very flat maximum at about 645W..

Example 15.-For producing the dye [Ii-ethyl- -diethylamino-benzthiazole-(2) l-[3-methyl-in dole- (2) l-trimethinecyanine iodide corresponding with the formula metrical carbo-cyanine from trimethyl-indol-- ethyl iodide may be removed by fractional crystallization.

In its alcoholic solution the dye shows an absorption maximum at a wave length of about 585ML.

Incorporated in a gelatino-silver-bromide emulsion containing about 4 per cent of silver iodide the dye imparts to it a range of sensitivity from about 510ml to about 700ml with a maximum at about G/iu.

Further dyes which may be prepared according to the methods described in the foregoing examples are:

l. [3-ethyl-6 diethylamino-benzthiazole- (2) [S-ethyl benzthiazole (2)] trimethinecyanine perchlorate corresponding with the formula (Gimme/6 7 s s 7 6 1| 1,1 1li H I1 I 5 2 2 5 wfo--C 4 I 02H5 C104 01H5 I CH N 7 s s 7 z s): le H I? l 6 5 2 2 5 a -C- a 4 N N 4 I :Hl :Hs

Incorporated in a gelatino-silver-bromide emulsion containing about 4 per cent of silver iodide the dye imparts to it a range of sensitivity from about 520ml. to about 710ML, with a maximum at about 630W..

3. [3-ethyl-6-diethylamino-benzthiazole- (2) [3ethyl-6-ethoxy-benzthiazole- (2) l -trimethinecyanine-perchlorate corresponding with the formula Absorption maximum of the alcoholic solution: about'603 mi.

Incorporated in a gelatine-silver-bromlde emulsion containing about 4 per cent of silver iodide the Vdye imparts to it a range of sensitivity from about 500ml to about '730ML with a maximum at about 645ML.

It is to be understood that our invention is not limited to the foregoing examples nor to the specific details given therein. Numerous other embodiments are possible and We contemplate as included within our invention all such modications and equivalents as fall within the scope of the appended claims.

The formulae of the dyes given herein repres- `ent the molecular structure `of our new dyes so far as to our actual knowledge. If, however; in future it should become evident that the formulae do not exactly correspond to the dyes this fact will not aiect our invention since the dyes will be easily identified by the method of producing the same which has been fully described in the examples. The maxima of sensitivity of our dyes are all very fiat and the values indicated may not be regarded too critical.

What we claim is:

1. A photographic material which comprises a silver halide emulsion containing a -trimethinecyanine salt which is unsymmetrical when the salt-forming anion is disregarded and which contains an amino group in at least one of the nuclei.

2. A photographic material which comprises a silver halide emulsion containing a carbocyanine salt, which is unsymmetrical when the salt-forming anion is disregarded, corresponding with the formula (the) quinll'ine nue eus emg W linked in 2 or 4 position) Y =S, Se Y'= Se, C(CH3)2, O /R W=H, N alkyl, alkoxyl R =H, alkyl, aryl, acyl,

X is an anion capable of precipatng a carbocyanine dye.

3. A photographic material which comprises a silver halide emulsion containing [3-ethyl-6-diethylamino-benzthiazole- (2) [3-ethy1 benzselenazole- (2) l-trimethinecyanine iodide corresponding with the formula 4. A photographic material which comprises a silver halide emulsion containing [3ethyl-6-diethylamino-benzthiazole- (2) [3-ethyl-6ethoxybenzthiazole- (2) l-trimethinecyanine perchlora te corresponding with the formula:

CzHs C104 02H5 5. A photographic material which comprises a silver halide emulsion containing [3-ethy1-5-diethylamino benzthiazole (2)] [3 ethyl 6- diethylamino benzthiazole (2)] trimethine cyanine perchlorate corresponding with the formula:

(Camm- 6 7 C1415 \Cl04 WALTER DIETERLE. WALTER ZEH.

WERNER ZERWECK.