US2439352A - Open chain active methylene color couplers - Google Patents

Description

Patented Apr. 6, 1948 OPEN CHAIN ACTIVE METHYLENECOLOR COUPLERS Arnold Weissberger and H ter, N. Y., assignors to Eastman Kodak Company, Rochester, N. Y., a corporation of New Jersey enryl). Porter, Roches- I No Drawing. ApplicationMarchZl, 1946; Serial No. 656,149

,' 12 Claims. (Cl. 95-6) This invention relates to photography and particularly to compounds which form dyes by coupling with the developing agent to produce colored images.

It is known that colored photographic images may be formed by using a developer which :produces a colored compound on development. The colored compound thus formed is deposited adjacent the silver grains of the silver image during the developing. colored image may be formed by adding to :certain developer solutions or by incorporating in. the silver halide emulsion .before or after exposure a compound which couples during development with the oxidation product of the developing agent and forms a colored compoundwhich is likewise deposited adjacent the silver grains of,

the silver image during development. Sucha compound which is employed in conjunction with a developing agent for the silver and which couples with the oxidation product :of the developing agent during development is referred 'to herein as a coupling compoundor coupler.

The present invention concerns new or 1111- proved color-forming developers comprising primary aromatic amino developing agent and a coupler as hereinafter defined and also includes a new or improved color development process which consists in developing a reducible silver salt image in a photographic element with theaid of a primary aromaticamino developer and in the presence of a coupler ashereinafter defined. It

lso includes photographic sensitive elements 5 aving such coupler in one or more emulsion ayers.

We have found that compounds of the following structure are valuable couplers for color photography and produce yellow to red images of high stability on development.

R-COCHzCONHCO-R ing solution or they may be of such size as to permit the use of these compounds in theemulsion layer of multi-layer photographic coatings.

In "the formula above, the substituent R may be an aryl radicalsuch as phenyl or naphthyl or It is also known that a 1 oflrisooomooNfloootm N-(benzoylacetyDbenzamide (2) CaHaCOCHzCONHCOCHa N-(bcnzoylacetyl)acetamide 4 -o o-oHz'ooNHo 0 com 'N-(fi-naphthbylacetyl)-benzamide N-acety1-a-(4,5-benzoiuroyl)-acetamide These compounds contain a coupling function which in thiscase is a reactive methylenegroup. By couplingfunction we mean a functionalor reactive group common tocoupler compounds which react with the development product of a primary aromatic-aminodeveloping agent. By

reactive methylene we mean a methylene group which is reactive in the coupling process, in this casethe group present between twonegative centers as in the group -CO-CHzCO--.

The aromatic amino developing agents used phenylenediamine-hydrochloride, dimethyl p phenylenediamine-hydrochloride and dimethylp-phenylenediamine sulphate. Developing agents containing heterocyclic systems as described in U. S. Patent 2,196,739 are also suitable. The paminophenols and their substitution products may also be used where the amino group is un substituted. All of these compounds have an unsubstituted amino group which enables the.

oxidation products of the developer to couple with the color-forming compounds to form a dye image.

The compounds of our invention may be prepared according to the following general reactions:

R'COCl RCOCHzC -v RCOOHQC Pyridine NCOR I II

-- RCO oHiooNHc on No OR I RGOCHQC III where R and R have the same meanings as stated above.

The starting imidoesters (l) were prepared from the reaction of ethanol and hydrogen chloride on the corresponding nitriles. The condensation of the imidoester with the acid chloride was carried out in excess pyridine with mild heating. The intermediate (II) was usually thrown out of solution as an oil by addition of water, and hydrolyzed directly to the amide derivative (III). In the case of the N-acetyl derivatives, the acid anhydride was used in place of the chloride, and the intermediates (II) were readily isolated in a pure state.

The following example illustrates a developing solution which may be used with the compounds of our invention.

grams p-Amino-diethylaniline sulfate 2 Sodium sulfite (anhydrous) 5 Sodium carbonate (anhydrous) 0 Potassium bromide 2 Water to 1 liter.

N-(Benzoylac'etyl) benz'amide grams..- 2 Sodium hydroxide (2% solution) cc 50 For use, B is added to A.

one or both sides of the support. The superposed layer may be differentially sensitized to record natural color photographic images in the wellknown manner.

' The examples and compounds set forth in the present specification are illustrative only and it is to be understood that our invention is limited only by the scope of the appended claims.

We claim:

l. A color-forming photographic developer comprising a primary aromatic amino developing agent and a coupler compound having the formula R-COCI-IsCONl-ICO-R where R is selected from the class consisting of aryl and benzofuroyl radicals and R is selected from the class consisting of alkyl and aryl radicals. 2. A color-forming photographic developer comprising a primary aromatic amino developing agent and a coupler compound having the formula R-COCHzCONI-ICO-R' where R is an aryl radical and R is an aryl radical.

3. A color-forming photographic developer comprising a primary aromatic amino developing agent and a coupler compound having the formula where R is a phenyl radical and R is a member of the group consistingof alkyl and aryl radicals;

4. A color-forming photographic developer comprising a primary aromatic amino develop- 7 ing agent and N-(benzoylacetyl) benzamide.

5. A color-forming photographic developer comprising a primary aromatic amino developing agent and N-benzoyl-a-(4,5-benzofuroyl)acetamide. V

v6. The method'of producing a colored photographic image in a silver halide emulsion layer which comprises exposing said layer and develop ing it with a primary aromatic amino developing agent in the presence of a coupler compound having the formula V Rr-COCH2CONHCO-R a where R is an aryl radical and R is an aryl radical. I

8. The method of producing a color photoa graphic image in a silver halide emulsion layer which comprises exposing said layer and developing it with a primary aromatic amino developing agent in the presence of a coupler compound hav- 7 ing the formula mooomoormco-H where R is a phenyl radical and R' is a member of the group consisting of alkyl and aryl radicals.

9. The method of producing a colored photographic image in a gelatino silver halide emulsion layer which comprises exposing said layerand developing it with a primary aromatic amino R-COCI-IzCONHCO-R' where R. is selected from the class consisting of aryl and benzoiuroyl radicals and R is selected from the class consisting of alkyl and aryl radicals.

12. A photographic emulsion for forming colored images comprises a gelatine silver halide emulsion having incorporated therein N-[m-(ptert.-Amylphenoxy) benzoyl] -a- [p- (p-sec.- amyl- 5 phenyl) benzoyl] acetamide.

ARNOLD WEISSBERGER. HENRY D. PORTER.

REFERENCES 011mb The following references are of record in the file of this patent:

UNITED STATES PATENTS 15 Number Name a Date 2,366,324 Frohlich Jan. 2, 1945 2,367,036 McQueen Jan. 9,1945