US3733196A - Chemically hardened silver halide emulsions containing tempering concentrations of simple organic polyols - Google Patents

Abstract

PHOTOGRAPHIC SILVER HALIDE ELEMENTS CONTAINING HYDROPHILIC COLLOIDS ARE TEMPERED BY SIMPLE ORGANIC POLYOLS HAVING THE FORMULAE:

(R-(CO)P)M-N(-H)(3-N-M)-(C(-CH2-OH)3)N

INDAN

WHEREIN R IS PHENYL OR SUBSTITUTED PHENYL, ALKYL, SUBSTITUTED ALKYL OR ALKENYL, P IS 0 OR 1, M IS 0, 1 OR 2, AND N IS 1 OR 2, THE SUM OF M AND N BEING AT MOST 3, OR

R''-OOC-C(-CH2-OH)3

WHEREIN R'' IS ALKYL, A HYDROGEN ATOM, AN ALKALI METAL OR THE ATOMS NECESSARY TO COMPLETE AN AMMONIUM SALT GROUP,

(HO-CH2)2-C<(-D-C(-CH2-OH)2-C(-R2)(-R3)-)

WHEREIN D IS THE ATOMS NEEDED TO COMPLETE A 5 OR 6 MEMBERED CARBOCYCLIC RING, AND TAKEN SEPARATELY, R2 IS HYDROGEN AND R3 IS HYDROXY, OR TAKEN TOGETHER R2 WITH R3 REPRESENTS AN XO-GROUP OR

O<(-CO-NH-C(-CH2-OH)2-CH2-), OR 1-(O=),2,2-DI(HO-CH2-)-

ALSO DISCLOSED ARE PROCESSES FOR EFFECTING TEMPERING OF VARIOUS LAYERS COMPRISING THESE POLYOLS AND POLYMERIC LATEX DISPERSIONS.

Description

U ited States Patent 3,733,196 CHEMICALLY HARDENED SILVER HALIDE EMULSIONS CONTAINING TEMPERING CONCENTRATIONS F SIMPLE ORGANIC POLYOLS Edward Peter Abel, Robert Stanley Darlak, and Louis Morton Minsk, Rochester, N.Y., assignors to Eastman Kodak Company, Rochester, NY. No Drawing. Filed Feb. 4, 1971, Ser. No. 112,768

Int. Cl. G03c 1/30 US. Cl. 96-111 12 Claims ABSTRACT OF THE DISCLOSURE Photographic silver halide elements containing hydrophilic colloids are tempered by simple organic polyols having the formulae:

wherein R is phenyl or substituted phenyl, alkyl, sub- 'stituted alkyl or alkenyl; p is 0 or 1; m is 0, 1 or 2; and

n is 1 or 2; the sum of m and n being at most 3; or

wherein R is alkyl, a hydrogen atom, an alkali metal or the atoms necessary to complete an ammonium salt group; or

wherein D is the atoms needed to complete a 5 or 6 membered carbocyclic ring; and taken separately, R is hydrogen and R is hydroxy, or taken together R with R represents an oxo-group or (I? o HN HOCHF' HOCH:

( 0 II onion GH2OH Also disclosed are processes for effecting tempering of various layers comprising these polyols and polymeric latex dispersions.

BACKGROUND OF THE INVENTION Field of the invention 3,733,196 Patented May 15, 1973 ice Description of the prior art It is well known that sensitometric characteristics, such as covering power, improved density loss on drying, stabilizing and the like, can be improved and attained by the addition of certain additives to light-sensitive composi tions, such as to layers and emulsions containing silver halide. It is also known that the physical properties often suffer after the introduction of such addenda. The various sensitometric properties, such as maximum optical density after the steps of exposure, processing and drying, depend only in part upon the amount of free silver which results from the development process. They also depend upon the manner in which the silver is laid down in preparation of the photographic element during manufacture and particularly upon the stresses to which it is subjected during drying and high temperature processing.

Photographic silver halide emulsions possessing increased covering power are of considerable interest and are particularly desirable since their use results in an increase in gamma and very often an increase in speed while the silver content is maintained at the same level. While covering power, and therefore silver density, can be thus increased, it is also essential that reduction in toughness of the photographic layer in the wet states be avoided. For example, it is generally the practice to employ hardening agents whose action on the hardenable colloid, which they effect, results in an increase in resistivity to elevated temperatures by chemical cross-linking.

The addition of such cross-linking agents is sometimes desirable in order to provide resistance to abrasion, to provide higher resistance to the elevated environmental temperatures of solutions and air drying chambers and to maintain the dimensional stability and integrity of the various coatings containing those colloids. These characteristics are particularly needed during processing photographic elements under modern, high temperature mechanical processing conditions. Nonetheless, while these colloid containing layers can be hardened by the simple expedient of increasing the concentration of the hardening agent used, such practice invariably causes a reduction in sensitometry such as the density of the image recorded from the light-sensitive emulsion. Consequently, in previous attempts to reduce or eliminate changes in covering power and to stabilize unwanted sensitometric variations and density-loss in photographic images recorded from silver halide emulsions containing a hardened hydrophilic colloid such as gelatin, various compensatory polymeric addenda have been used. Even so, when these polymeric addenda, such as for example, polyacrylamide, poly[N-(Z-hydroxyethyl)acrylamide], poly(vinyl pyrrolidone), poly(N-acrylylmorpholine) and the like, are added, frequently jointly with other additives such as polymeric latexes, even the beneficial effect of the covering power addenda is often lost or appreciably diminished because the emulsion layer and other layers are softened. By polymeric latex, it will be understood that we mean a colloidal dispersion of a substantially insoluble polymer in an essentially aqueous system.

While it can be possible for a polymer composition to achieve the above desirable effects in both all-colloid systems, e.g. gelatin, and in colloid mixtures such as colloidpolymer combinations, without causing softening or mushiness of the colloid coating, it is believed that great advantages exist in providing non-polymeric, low molecular weight compounds as tempering agents or tougheners when combined with the covering power addenda. This is so because of the relative ease of preparation of the toughener addends, their lack of adverse interference with physical properties and sensitometry and their ease of addition to the photographic elements which contain wide varieties of other addenda.

The art would be greatly enhanced by hydrophilic colloid-containing compositions which could effectively, economically and conveniently utilize the advantages of relative flexibility, toughness, rigidity, lack of dimensional change and the like possessed by elements having combined therein, the tempering agents such as the simple organic polyol toughener compounds disclosed. The unexpected advantages would be derived from the combination of substances which produce physical and sensitometric stability such as density on drying of colloid-containing systems While still providing significant tempering of the colloids contained in various of the coated layers such as emulsions.

SUMMARY OF THE INVENTION wherein R is phenyl, substituted phenyl such as o-methoxyphenyl, 2,4-dichlorophenyl, p-tolyl, p-bromophenyl, 2,4-xylyl, p-acetylphenyl, p-biphenylyl and the like; alkyl of up to 8 carbon atoms such as methyl, ethyl, propyl, isopropyl, butyl, hexyl, octyl and the like; substituted alkyl such as hydroxymethyl, methoxymethyl, hydroxyethyl, 3-chloropropyl, benzyl, and the like; or alkenyl such as vinyl, allyl, butadienyl, and the like; p is or 1; m is O, 1 or 2; and n is 1 or 2; the sum of m and n being at most 3; or

wherein R is an alkyl gorup of from 1 to 8 carbon atoms such as ethyl, propyl, butyl, pentyl, hexyl, octyl and the like; a hydrogen atom, an alkali metal such as sodium, potassium and the like or the atoms necessary to complete an ammonium salt group, especially the organic ammonium salt group (III) R: Ra

(HOCHzh-C 0 CH1 on): I .D I

wherein D is the atoms needed to complete a 5 or 6 membered carbocyclic ring such as a cyclopentane or cyclohexane ring for example; optionally having a 6-membered alicyclic or aromatic ring fused thereto such as a benzocycloheptane, benzocyclo hexane, perhydronaphthalene, or a perhydroindan fused ring group; taken separately R is hydrogen and R is hydroxy, or taken together R with R represents an oxo-group or HOCII U HOCHz onion CHzOH A number of compounds within the above formulae exhibit especially good properties and are particularly effective tempering addends. For example among those hydroxyalkylaminoakane polyols having Formula I are 2-(2-hydroxyethylamino) -2-hydroxymethyl)-1,3-propanediol or 2[bis(2 hydroxyethyl)amino] 2-(hydroxymethyl)-1,3-

propanediol.

From the oxo-compounds of structural Formula III preferred compounds are those wherein D forms a 6- membered ring optionally having a ring fused thereto such as 2,2,6,6-tetramethylolcyclohexanol,

2,2,5,5-tetramethylolcyclopentanol and 1,1,3,3-tetramethylol-2-decalone also those having the structural formulae of IV or V namely, 2,2 dimethylolindanone or 4,4-dimethylol-2- oxazolidone.

These compounds can be used without significant adverse sensitometric effects in any effective concentration such as for example from about 5 percent to about 50 percent based upon the weight of the organic colloid in the layer.

By use of the term tempering it will be understood to mean imparting to a hydrophilic colloid by an addend or agent, a high degree of rigidity or structural toughness resembling well-known hardening characteristics achieved heretofore by chemical cross-linking agents. When added to hydrophilic colloids such as photographic silver halide colloid-containing elements to toughen the various colloids therein, the tempering agents disclosed herein unexpectedly provide a high degree of toughness to those colloids Without adversely affecting the sensitometric characteristics as chemical cross-linking agents sometimes do.

While the compounds, disclosed herein to achieve the desirable and unexpected properties set forth, are generally classified as simple organic polyols, they include various cyclic compounds and they are distinguished from those poly-hydroxy type compounds such as glycerol or glycol whose previous disclosed use in photographic gelatin emulsions has been as plasticizers. 'Plasticizing or softening is virtually the opposite of the action of the polyols used in the practice of this invention since the former is a softening and the latter, rigidizing or tempering. By the use of the term mushiness as applied to colloid-layers herein, it will be understood to mean the physical property of softness as determined in the numerical values recorded by a weighted stylus drawn across said layers.

Accordingly, it is an object of this invention to provide improved light-sensitive emulsions, comprising a hydrophilic colloid, these emulsions exhibiting improved sensitometric properties such as covering power, decreased density loss on drying, and improved toughness, said improved toughness being achieved without adversely effecting the desired sensitometric characteristics of the emul- SlOIlS.

It is another object to provide simple polyol compounds which, when added to silver halide emulsions containing covering power addenda, toughen and temper said emulsions while still maintaining effective covering power.

It is still another object of this invention to provide novel colloidal compositions such as improved colloidal 1ehmulsions and the various photographic elements utilizing It is yet another object to provide processes for imparting improved physical and chemical characteristics to colloids and photographic colloid-containing compositions utilizing simple tempering organic polyols having the formulae as disclosed herein.

It is another object to provide, for use in said processes, novel compositions which impart increased toughness, reduced mushiness without substantially and adversely affecting the sensitometric properties of colloids and photographic colloidal emulsion coatings.

DESCRIPTION OF PREFERRED EMBODIMENTS In accordance with this invention, the above objects are attained with polyol compounds having the formulae:

I o i: 1 N(H)3-nm [O(CH2OH)3] D m I! wherein R is phenyl, substituted phenyl such as o-methoxyphenyl, 2,4-dichlorophenyl, p'tolyl, p-bromophenyl, 2, 4-xylyl, p-acetylphenyl, p-biphenylyl and the like; alkyl of up to 8 carbon atoms such as methyl, ethyl, propyl, isopropyl, butyl, hexyl, octyl and the like; substituted alkyl such as hydroxymethyl, methoxymethyl, hydroxyethyl, 3- chloropropyl, benzyl, and the like; or alkenyl such as vinyl, allyl, butadienyl, and the like; p is or 1; m is 0, 1 or 2; and n is 1 or 2; the sum of m and n being at most 3; or

rv-o-d-owmorn,

wherein R is an alkyl group of from 1 to 8 carbon atoms such as ethyl, propyl, butyl, pentyl, hexyl, octyl and the like; a hydrogen atom, an alkali metal such as sodium, potassium and the like or the atoms necessary to complete an ammonium salt group, especially the organic ammonium salt group I (HO CHz)aCNHa- (III) R2 R3 (HO CHzh-C C(CHZOHM wherein D is the atoms needed to complete a 5 or 6 membered carbocyclic ring such as a cyclopentane or cyclohexane ring for example; optionally having a 6-membered alicyclic or aromatic ring fused thereto such as a benzocycloheptane, benzocyclo hexane, perhydronaphthalene, or a perhydroindon fused ring group; taken separately R is hydrogen and R is hydroxy, or taken together R with R represents an oxo-group or H0 CH HI\( 0 HOCH:

CHzOH ample, silver salts, like the halides, such as silver chloride, silver bromide, silver chlorobromide and the like. These silver halide-containing emulsions can contain a binding agent such as all-gelatin and gelatin derivatives, all-nongelatin, and mixtures thereof such as gelatin and a soluble extender polymer system or gelatin and latex polymer, or various combinations of gelatin, latex and soluble polymers, as set forth herein.

In another preferred embodiment, a polymeric covering power addendum is employed in a photographic silver halide emulsion and said emulsion is toughened by the addition of the tempering compounds set forth above without adverse loss of sensitometry diminution of covering power or softening.

Another embodiment comprises substantially dried layers derived from a combination of a gelatin sol and a latex resulting from the polymerization of a substantially water insoluble alkyl ester of an ethylenically unsaturated acid.

These compounds provide the unexpected property of tempering the emulsion coating despite the usual tendency of various addenda, such as covering power addenda, to soften the emulsion coating.

It is now found that the compounds disclosed herein and used in the practice of this invention with various covering power addenda, impart superior physical and chemical characteristics to photographic compositions and obviate the excessive softening often incident to increased covering power.

The polyols useful in this invention which conform to structure I can be prepared by the addition of the appropriate acid chloride to tris (hydroxymethyl)methylarnine or by the action of tris (hydroxymethyl)methylamine on an alkyl or substituted alkyl halide. Compounds of structure II are prepared by the direct esterification of the acid with the corresponding alcohol. Compounds of structure IH and IV are prepared by the reaction of formaldehyde with the carbocyclic ketone in the presence of a base such as calcium oxide. Compounds having the structure of formula IV are prepared by the action of phenyl chloroformate on tris(hydroxymethyl)methylamine.

The silver halide emulsions used with this invention can comprise silver chloride, silver bromide, silver bromoiodide, silver chlorobromoiodide or mixtures thereof. The emulsions can be coarse or fine grain and can be prepared by any of the well-known procedures, e.g. single jet emulsions, double jet emulsions, such as Lippmann emulsions, ammoniacal emulsions, thiocyanate or thioether ripened emulsions such as those described in Nietz et al. U.S. Pat. 2,222,264 issued Nov. 19, 1940; Illingsworth U.S. Pat. 3,320,069 issued May 16, 1967; and McBride U.S. Pat. 3,271,157 issued Sept. 6, 1966. Surface image emulsions can be used or internal image emulsions such as those described in Davey et al. U.S. Pat. 2,592,250 issued May 8, 1952; Porter et a1. U.S. Pat. 3,206,313 issued Sept. 14, 1965; Berriman U.S. Pat. 3,367,778 issued Feb. 6, 1968; and Bacon et al. U.S. Pat. 3,447,927 issued June 3, 1969. If desired, mixtures of surface and internal image emulsions can be used as described in Luckey et al. U.S. Pat. 2,996,382 issued Aug. 15, 1961. Negative type emulsions can be used or direct positive emulsions such as those described in Leermakers U.S. Pat. 2,184,013 issued Dec. 19, 1939; Kendall et al. U.S. Pat. 2,541,472 issued Feb. 13, 1951; Berriman U.S. Pat. 3,367,778 issued Feb. 6, 1968; Schouwenaars British Pat. 723,019 issued Feb. 2, 1955; Illingsworth 'et al. French Pat. 1,520,821 issued Mar. 4, 1968; Ives U.S. Pat. 2,563,785 issued Aug. 7, 1951; Knott et al. U.S. Pat. 2,456,953 issued Dec. 21, 1948, and Land U.S. Pat. 2,861,885 issued Nov. 25, 1958. The emulsions can be regular grain emulsions such as the type described in Klein and Moisar, J. Phot. Sci, vol. 12, No. 5, September/October, 1964, pp. 242-251.

The silver halide emulsions used with this invention can be unwashed or washed to remove soluble salts. In the latter case the soluble salts are removed by chillsetting and leaching or the emulsion can be coagulation washed, e.g. by the procedures described in Hewitson et al. U.S. Pat. 2,618,556 issued Nov. 18, 1952; Yutzy et al. U.S. Pat. 2,614,928 issued Oct. 21, 1952; Yackel U.S. Pat. 2,565,418 issued Aug. 21, 1951; Hart et al. U.S. Pat. 3,241,969 issued Mar. 22, 1966; and Waller et a1. U.S. Pat. 2,489,341 issued Nov. 29, 1949.

The emulsions used with this invention can be sensitized with chemical sensitizers, such as with reducing agents; sulfur, selenium or tellurium compounds; gold, platinum or palladium compounds; or combinations of these. Suitable procedures are described in Sheppard et al. U.S. Pat. 1,623,499 issued Apr. 5, 1927; Waller et al. U.S. Pat. 2,399,083 issued Apr. 23, 1946; McVeigh U.S. Pat. 3,297,447 issued Jan. 10, 1967; and Dunn U.S. Pat. 3,297,446 issued Jan. 10, 1967.

The silver halide emulsions used with this invention can contain speed increasing compounds such as polyalkylene glycols, cationic surface active agents and thioethers or combinations of these as described in Piper U.S. Pat. 2,886,437 issued May 12, 1959; Dann et al. U.S. Pat. 3,046,134 issued July 24, 1962; Carroll et al. U.S. Pat. 2,944,900 issued July 12, 1960; and Gotfe U.S. Pat. 3,294,540 issued Dec. 27, 1966.

The silver halide emulsions used in the practice of this invention can be protected against the production of fog and can be stabilized against loss of sensitivity during keeping. Suitable antifoggants and stabilizers each used alone or in combination include thiazolium salts described in Brooker et al. U.S. Pat. 2,131,038 issued Sept. 27, 1938, and Allen et al. U.S. Pat 2,694,716 issued Nov. 16, 1954; the azaindenes described in Piper U.S. Pat. 2,886,- 437 issued May 12, 1959; and Heimbach et al. U.S. Pat. 2,444,605 issued July 6, 1948; the mercury salts as described in Allen et a1. U.S. Pat. 2,728,663 issued Dec. 27, 1955; the urazoles described in Anderson et al. U.S. Pat. 3,287,135 issued Nov. 22, 1966; the sulfo-catechols described in Kennard et al. U.S. Pat. 3,236,652 issued Feb. 22, 1966; the oximes described in Carroll et al. British Pat. 623,448 issued May 18, 1949; nitron; nitroindazoles; the mercaptotetrazoles described in Kendall et al. U.S. Pat. 2,403,927 issued July 16, 1946; Kennard et al. U.S. Pat. 3,266,897 issued Aug. 16, 1966, and Luckey et al. U.S. Pat. 3,397,987 issued Aug. 20, 1968; the polyvalent metal salts described in Jones U.S. Pat. 2,839,405 issued June 17, 1958; the thiuronium salts described in Herz et al. U.S. Pat. 3,220,839 issued Nov. 30, 1965; the palladium, platinum and gold salts described in Trivelli et al. U.S. Pat. 2,566,263 issued Aug. 28, 1951, and Yutzy et a1. U.S. Pat. 2,597,915 issued May 27, 1952.

The photographic elements of this invention can contain incorporated developing agents such as hydroquinones, catechols, aminophenols, 3-pyrazolidones, ascorbic acid and its derivatives, reductones and phenylenediamines. Combinations of developing agents can be employed in the practice of the invention. The developing agents can be in a silver halide emulsion and/or in another suitable location in the photographic element. The developing agents can be added from suitable solvents or in the form of dispersions as described in Yackel U.S. Pat. 2,592,368

issued Apr. 8, 1952 and Dunn et al., French Pat. 1,505,778. The photographic and other hardenable layers used in the practice of this invention can be hardened by various organic or inorganic hardeners, alone or in combination, such as the aldehydes, and blocked aldehydes, ketones, carboxylic and carbonic acid derivatives, sulfonate esters sulfonyl halides and vinyl sulfonyl ethers, active halogen compounds, epoxy compounds, aziridines, active olefins, isocyanates, carbodiimides, mixed function hardeners and polymeric hardeners such as oxidized polysaccharides like dialdehyde starch and oxyguar gum and the like.

The photographic emulsions and elements described in the practice of this invention can contain various colloids alone or in combination as vehicles, binding agents and various layers. Suitable hydrophilic materials include both naturally-occurring substances such as proteins, for example, gelatin, gelatin derivatives, cellulose derivatives, polysaccharides such as dextran, gum arabic and the like; and synthetic polymeric substances such as water soluble polyvinyl compounds like poly(vinylpyrrolidone), acrylamide polymers and the like.

The described photographic emulsion layers and other layers of a photographic element empolyed in the practice of this invention can also contain alone or in combination with hydrophilic, water permeable colloids, other synthetic polymeric compounds such as dispersed vinyl compounds such as in latex form and particularly those which increase the dimensional stability of the photographic materials. Suitable synthetic polymers include those described, for example, in Nottorf U.S. Pat. 3,142,568 issued July 28, 1964; White U.S. Pat. 3,193,386 issued July 6, 1965; Houck et al. U.S. Pat. 3,062,674 issued Nov. 6, 1962; Houck et al. US. Pat. 3,220,844 issued Nov. 30, 1965; Ream et al. U.S. Pat. 3,287,289 issued Nov. 22, 1966; and Dykstra U.S. Pat. 3,411,911 issued Nov. 19, 1968; particularly effective are those water-insoluble polymers of alkyl acrylates and methylacrylates, acrylic acid, sulfoalkyl acrylates or methacrylates, those which have crosslinking sites which facilitate hardening or curing, those having recurring sulfobetaine units as described in Dykstra Canadian Pat. 774,054.

The photographic elements used with this invention can contain antistatic or conducting layers, such layers can comprise soluble salts, e.g. chlorides, nitrates, etc., evaporated metal layers, ionic polymers such as those described in Minsk U.S. Pat. 2,861,056 issued Nov. 18, 1958 and Sterman et al., U.S. Pat. 3,206,312 issued Sept. 14, 1965 or insoluble inorganic salts such as those described in Trevoy U.S. Pat. 3,428,451 issued Feb. 18, 1969.

In addition, the photographic layers and other layers of a photographic element employed and described herein can be coated on a wide variety of supports. Typical supports include cellulose nitrate film, cellulose ester film, poly(vinyl acetal) fihn, polystyrene film, poly(ethylene terephthalate) film, polycarbonate film and related films or resinous materials, as well as glass, paper, metal and the like. Typically, a flexible support is employed, especially a paper support, which can be partially acetylated or coated with baryta and/ or an alphaolefin polymer, particularly a polymer of an alpha-olefin containing 2 to 10 carbon atoms such as polyethylene, polypropylene, ethylenebutene copolymers and the like.

The photographic layers employed in the practice of this invention can contain plasticizers and lubricants such as polyalcohols, e.g. glycerin and diols of the type described in Milton et al., U.S. Pat. 2,960,404 issued Nov. 1, 1966; fatty acids or esters such as those described in Robijns U.S. Pat. 2,588,765 issued Apr. 11, 1952, and Duane U.S. Pat. 3,121,060 issued Feb. 11, 1964; and silicone resins such as those described in Du Pont British Pat. 955,061 issued Apr. 15, 1964.

The photographic layers employed in the practice of this invention can contain surfactants such as saponin; anionic compounds such as the alkyl aryl sulfouates described in Baldsiefen U.S. Pat. 2,600,831 issued June 17, 1952; amphoteric compounds such as those described in Ben-Ezra U.S. Pat. 3,133,816 issued May 19, 1964; and water soluble adducts of glycidol and an alkyl phenol such as those described in Olin Mathieson British Pat. 1,022,878 issued Mar. 16, 1966.

The photographic elements employed in the practice of this invention can contain matting agents such as starch, titanium dioxide, zinc oxide, silica, polymeric beads including beads of the type described in Jelley et al., U.S. Pat. 2,992,101 issued July 11, 1961 and Lynn U.S. Pat. 2,701,245, issued Feb. 1, 1955.

The photographic elements used in this invention can contain brightening agents including stilbenes, triazines, oxazoles and coumarin brightening agents. Water soluble brightening agents can be used such as those described in Alberz et al., German Pat. 972,067 and McFall et al. U.S.

9 Pat. 2,933,390 issued Apr. 19, 1960 or dispersions of brighteners maybe used such as those described in Jansen German Pat. 1,150,274, Oetiker et al., U.S. Pat. 3,406,070 issued Oct. 15, 1968 and Heidke French Pat. 1,530,244.

Spectral sensitizing dyes can be used conveniently to confer additional sensitivity to the light sensitive silver halide emulsion of the multilayer photographic elements of the invention. For instance, additional spectral sensitization can be obtained by treating the emulsion with a solution of a sensitizing dye in an organic solvent or the dye can be added in the form of a dispersion as described in Owens et al. British Pat. 1,154,781 issued June 11, 1969. For optimum results, the dye is either added to the emulsion as a final step or at some earlier stage.

Sensitizing dyes useful in sensitizing such emulsions are described, for example, in Brooker et al. U.S. Pat. 2,526,632 issued Oct. 24, 1950; Sprague U.S. Pat. 2,503,776 issued Apr. 11, 1950; Brooker et al. U.S. Pat. 2,493,748 issued Jan. 10, 1950; and Taber et al. U.S. Pat. 3,384,486 issued May 21, 1968. Spectral sensitizers which can be used include the cyanines, merocyanines, complex (tri or tetranuclear) merocyanines, complex (trior tetranuclear) cyanines, holopolar cyanines, styryls, hemicyanines (e.g. enamine hemicyanines), oxonols and hemioxonols.

Dyes of the cyanine classes can contain such basic nuclei as the thiazolines, oxazolines, pyrrolines, pyridines, oxazoles, thiazoles, selenazoles and imidazoles. Such nuclei can contain alkyl, alkylene, hydroxyalkyl, sulfoalkyl, carboxyalkyl, aminoalkyl and enamine groups and can be fused to carboxylic or heterocyclic ring systems either unsubstituted or substituted with halogen, phenyl, alkyl, haloalkyl, cyano, or alkoxy groups. The dyes can be symmetrical or unsymmetrical and can contain alkyl, phenyl, enamine or heterocyclic substituents on the methine or polymethine chain.

The merocyanine dyes can contain the basic nuclei mentioned above as well as acid nuclei such as thiohydantoins, rhodaniones, oxazolidenediones, thiazolidenediones, barbituric acids, thiazolineones, and malononitrile. These acid nuclei can be substituted with alkyl, alkylene, phenyl, carboxyalkyl, sulfoalkyl, hydroxyalkyl, alkoxyalkyl, alkylamino groups, or heterocycic nuclei. Combinations of these dyes can be used, if desired. In addition, supersensitizing addenda which do not absorb visible light can be included, for instance, ascorbic acid derivatives, azaindenes, cadmium salts, and organic sulfonic acids as described in McFall et al. U.S. Pat. 2,933,390 issued Apr. 19, 1960, and Jones et al. U.S. Pat. 2,937,089 issued May 17, 1960.

The various layers, including the photographic layers, employed in the practice of this invention can contain light absorbing materials and filter dyes such as those described in Sawdey U.S. Pat. 3,253,921 issued May 31, 1966; Gaspar U.S. Pat. 2,274,782 issued Mar. 3, 1942; Silberstein et al. U.S. Pat. 2,527,583 issued Oct. 31, 1950, and VanCampen U.S. Pat. 2,956,879 issued Oct. 18, 1960. If desired, the dyes can be mordanted, for example, as described in Milton et al. U.S. Pat. 3,282,699 issued Nov. 1, 1966.

The sensitizing dyes and other addenda used in the practice of this invention can be added from water solutions or suitable organic solvent solutions can be used. The compounds can be added using various procedures including those described in Collins et al. U.S. Pat. 2,912,- 343 issued Nov. 10, 1959; McCrossen et al., U.S. Pat. 3,342,605 issued Sept. 19, 1967; Audran U.S. Pat. 2,996,- 287 issued Aug. 15, 1961 and Johnson et al., U.S. Pat. 3,425,835 issued Feb. 14, 1969.

The photographic layers used in the practice of this invention can be coated by various coating procedures including dip coating, air knife coating, curtain coating, or extrusion coating using hoppers of the type described in Beguin U.S. Pat. 2,681,294 issued June 15, 1954. If

desired, two or more layers may be coated simultaneously by the procedures described in Russell U.S. Pat. 2,761,791 issued Sept. 4, 1956 and Wynn British Pat. 837,095. This invention also can be used for silver halide layers coated by vacuum evaporation as described in British Pat. 968,- 453 and LuValle et al. U.S. Pat. 3,219,451 issued Nov. 23, 1965.

This invention can be used with elements designed for color photography, for example, elements containing color-forming couplers such as those described in Frohlich et al. U.S. Pat. 2,376,679 issued May 22, 1945; Jelley et al., U.S. Pat. 2,322,027 issued June 15, 1943; Fierke et al., U.S. Pat. 2,801,171 issued July 30, 1957; Godowsky U.S. Pat. 2,698,794 issued Jan. 4, 1955; Barr et al., U.S. Pat. 3,227,554 issued Jan. 4, 1966; and Graham et al. U.S. Pat. 3,046,129 issued July 24, 1962; or elements to be developed in solutions containing color-forming couplers such as those described in Mannes et al. U.S. Pat. 2,252,-

718 issued Aug. 19', 1941; Carroll et al., U.S. Pat. 2,592,- 243 issued Apr. 18, 1952; and Schwan et al., U.S. Pat. 2,950,970 issued Aug. 30, 1966; and in false-sensitized color materials such as those described in Hanson U.S. Pat. 2,763,549 issued Sept. 18, 1956.

Photographic elements prepared according to this invention can be processed by various methods including processing in alkaline solutions containing conventional developing agents such as hydroquinones, catechols, aminophenols, 3-pyrazolidones, phenylenediamines, ascorbic acid derivatives, hydroxylamines, hydrazines, reductones and the like; web processing such as described in Tregillus et al. U.S. Pat. 3,179,517 issued Apr. 20, 1965; stabilization processing as described in Russell et al. Stabilization Processing of Films and Papers, PSA Journal, vol. 16B, August 1950; monobath processing as described in Levy Combined Development and Fixation of Photographic Images with Monobaths, Phot. Sci. and Eng, vol. 2, No. 3, October 1958, and Barnes et al. U.S. Pat. 3,392,- 019 issued July 9, 1968. If desired, the photographic elements of this invention can be processed in hardening developers such as those described in Allen et al., U.S. Pat. 3,232,761 issued Feb. 1, 1966; in roller transport processors such as those described in Russell et al., U.S. Pat. 3,025,779 issued Mar. 20, 1962; or by surface application processing as described in Example 3 of Kitze U.S. Pat. 3,418,132 issued Dec. 24, 1968.

The silver halide emulsions used with this invention can be used for making lithographic printing plates such as by the colloid transfer of undeveloped and unhardened areas of an exposed and developed emulsion to a suitable support as described in Clark et al. U.S. Pat. 2,763,553 issued Sept. 18, 1956; to provide a relief image as described in Woodward U.S. Pat. 3,402,045 issued Sept. 17, 1968 or Spencer U.S. Pat. 3,053,658 issued Sept. 11, 1962; to prepare a relief printing plate as described in Baxter et al. U.S. Pat. 3,271,150 issued Sept. 6, 1966.

This invention can be used with elements designed for colloid transfer processes such as described in Yutzy et al. U.S. Pat. 2,716,059 issued Aug. 23, 1953; silver salt diifusion transfer processes such as described in Rott U.S. Pat. 2,352,014 issued June 20, 1944; Land U.S. Pat. 2,543,- 181 issued Feb. 27, 1951; Yacket et al. U.S. Pat. 3,020,155 issued Feb. 6, 1962; and Land U.S. Pat. 2,861,885 issued Nov. 25, 1958; color image transfer processes such as described in Rogers U.S. Pats. 3,087,817 issued Apr. 30, 1963; 3,185,567 issued May 25, 1965; and 2,983,606 is sued May 9, 1961; Weyerts et al. U.S. .Pat. 3,253,915 issued May 31, 1966; Whitmore et al. U.S. Pat. 3,227,550 issued Jan. 4, 1966; Barr et al. U.S. Pat. 3,227,551 issued Jan. 4, 1966; Whitmore et al. U.S. Pat. 3,227,552 issued Jan. 4, 1966; and Land U.S. Pats. 3,415,644 issued Dec. 10, 1968; 3,415,645 issued Dec. 10, 1968; and 3,415,646 issued Dec. 10, 1968; and imbibition transfer processes as described in Minsk U.S. Pat. 2,882,156 issued Apr. 14, 1959.

This invention may be used in elements designed for recording print out images as described in Fallesen U.S. Pat. 2,369,449 issued Feb. 13, 1945 or Bacon et a1. U.S. Pat. 3,447,927 issued June 3, 1969; direct print images as described in Hunt U.S. Pat. 3,033,682 issued May 8, 1962 and McBride U.S. Pat. 3,287,137 issued Nov. 22, 1966; elements designed for processing by heat as described in Soresen et al. U.S. Pat. 3,152,904 issued Oct. 13, 1964; Morgan et al. U.S. Pat. 3,457,075 issued July 22, 1969; Stewart et al. U.S. Pat. 3,312,550 issued Apr. 4, 1967 and Colt U.S. Pat. 3,418,122 issued Dec. 24, 1968.

This invention can be used in elements designed for physical development such as those described in Agfa British Pat. 920,277 and Gilman et al. British Pat. 1,131,238.

Hydrophilic colloid materials which can be used in the practice of the invention include various waterperrneable binder vehicles which materials can be suspended in colloidal dispersions. Hydrophilic colloids suitable as binder vehicles and layers include proteinaceous compounds such as, for example, gelatin, colloidal albumin and other hydrophilic colloids such as, for example, polyvinyl compounds, cellulose derivatives, acrylamide polymers, etc., though gelatin materials are preferred. The high molecular weight materials for binder vehicles and layers which are generally considered soluble in aqueous solutions and do not form small discrete particles when mixed with an aqueous gelatin emulsion, as can be determined upon observation of a photomicrograph, can be considered hydrophilic colloids for purposes of this invention.

The synthetic polymeric latex materials referred to herein are generally polymeric materials which are relatively insoluble in water compared to water-soluble polymers, but have sufiicient water solubility to form colloidal suspensions of small polymeric micelles. Typical latex polymeric materials can be made by rapid copolymerization with vigorous agitation in a liquid carrier, of at least one monomer which would form a hydrophobic homopolymer and at least one monomer which would form a hydrophilic homopolymer. In certain preferred embodiments, from about 1 to about 30%, by weight, of units of monomer containing the water-solubilizing group is present in the copolymer product. Copolymers prepared by this method and analogous methods provide discrete micelles of the copolymer which have low viscosities in aqueous suspensions. Typical useful copolymers include interpolymers of acrylic esters and sulfoesters as disclosed in Dykstra, U.S. Pat. 3,411,911 issued Nov. 19, 1968, interpolymers of acrylic esters and sulfobetaines as described in Dykstra and Whiteley, U.S. Pat. 3,411,912 issued Nov. 19, 1968, interpolymers of alkyl acrylates and acrylic acids as disclosed in Ream and Fowler, U.S. Pat. 3,287,289 issued Nov. 22, 1966, interpolymers of vinyl acetate, alkyl acrylates and acrylic acids as disclosed in Corey, U.S. Pat. 3,296,169 issued Jan. 3, 1967, and interpolymers as disclosed in Smith U.S. Ser. No. 525,272 filed Dec. 20, 1965. Polymeric latex materials can also be made by rapid polymerization with vigorous agitation of hydrophobic polymers when polymerized in the presence of high concentrations of surfactants which contain water-solubilizing groups. Generally good latex materials are also disclosed in Nottorf U.S. Pat. 3,142,568 issued July 28, 1964; White U.S. Pat. 3,193,386 issued July 6, 1965; Houck et al., U.S. Pat. 3,062,674 issued Nov. 6, 1962; and Houck et al., U.S. Pat. 3,220,844 is sued Nov. 30, 1965.

In one embodiment, the latex polymers which can be used according to this invention are acrylic interpolymers, i.e. those interpolymers prepared from polymerizable 12 acrylic monomers containing the characteristic acrylic group Such polymers are conveniently prepared by the interpolymerization of an acrylic monomer with at least one dissimilar monomer which can be another acrylic monomer or some other different polymerizable ethylenically unsaturated monomer. It is, of course, understood that the acrylic interpolymers employed in the practice of this invention are compatible with gelatin and have a T of less than 20 C. (T can be calculated by differential thermal analysis as disclosed in Techniques and Methods of Polymer Evaluation, vol. 1, Marcel Dekker, Inc., NY. 1966).

In one embodiment, preferred interpolymers which can be used in this invention comprise units of an alkyl acrylate such as, for example, methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylates (e.g. n-butyl or t-butyl acrylates), amyl acrylates, hexyl acrylates and the like. Acrylic interpolymers containing units of acrylic acid or a sulfoester acrylate are especially useful in the process. Typical polymers of this type are copoly(butyl acrylate-acrylic acid), copoly(methyl acrylate-acrylic acid), copoly(ethyl acrylateacrylic acid), copoly(butyl acrylate-sulfopropyl acrylate) and the like. Additional examples of suitable polymers are disclosed in U.S. Pat. 3,459,790 issued Aug. 5, 1969 to Smith. In a preferred embodiment, the copolymer comprises up to about 30%, by weight, of acrylic acid or the sulfoester acrylate; especially good results being obtained with latex alkyl acrylate copolymers having up to about 20 percent, by weight, of the acrylate acid or the sulfoester acrylate. High ratios of solubilizing groups, such as the acrylic acid groups or the sulfoester groups produce a more soluble solutiontype polymer with respect to water carrier solvents and, therefore, preferably concentrations of about 5 to about 25 percent by weight are utilized to provide the better latex polymers, depending on the molecular weight of the monomer unit. Mixtures of the more soluble solutiontype polymers and the latex polymers can also be used within the scope of this invention to achieve the desired emulsion characteristics. The acrylic interpolymer generally comprises at least 10 percent and to about 99 percent, by weight, of the binder vehicle for the emulsion. In the preferred embodiments, the binder vehicle comprises from about 25 to about percent of the acrylic interpolymer and from about 75 percent to about 25 percent, by weight, gelatin of the total binder. Generally the emulsion comprises less than 100 grams of gelatin per mole of silver halide in the emulsion to permit fast drying times of the developed emulsion. Preferably the emulsion comprises less than 75 grams of gelatin per mole of silver halide.

In another preferred embodiment of this invention, the above-mentioned copolymers contain units of a third monomer. Exceptionally good results are obtained in the process of this invention when the synthetic polymers comprise units of 1) alkyl acrylates, (2) acrylic acid or sulfoester acrylates and (3) an acrylic monomer unit having active methylene groups in side chains such as in malonic ester groups, acetoacetic ester groups, cyanoacetic ester groups or 1,3-diketone groups such as disclosed in Smith U.S. Pat. 3,488,708 issued Jan. 6, 1970. Typical polymers of this class include copoly(ethyl acrylate-acrylic acid 2 acetoacetoxy ethyl methacrylate), copoly(butyl acrylate-sodium acryloxy propane sulfonate 2 aceto-acetoxyethyl methacrylate), copoly- (methyl acrylate-sodium acryl-oyloxypropane sulfonate- 2-acetoacetoxycthyl methacrylate), copoly(butyl acrylateacrylic acid 2 cyanoacetoxyethyl methacrylate) and the like and mixtures thereof.

Results obtained from the following examples indicate that known covering power addenda such as polyacrylamide and poly(vinyl B hydroxyethylcarbamylmethylearbamate), produce a marked softening or mushiness in photographic elements processed in both an automatic processor and the other known methods. These addenda also produce increased vertical swelling of the emulsion in water and a concomitant increase in mushiness of the gelatin layer. In contrast thereto, the polyol addenda useful in this invention in the same concentrations produce less mushiness and a significant increase in toughness and resistivity to deterioration of the physical integrity of the element. When these polyols are used in combination with the covering power addenda, substantial rigidity and toughness is noted by the decrease in percent vertical swell.

One test used to determine mushiness, i.e. lack of toughening, of the various colloid layers, involves the relative firmness or wet jelly strength of the various layers such as the gelatin emulsion layers or pelloid layers. These values are obtained based on a colloid-containing photographic element such as film or paper after removal from the processing solution, for example developer. The element is then drawn beneath a weighted stylus having a hard sapphire point on which the weighted force is varied, such as gradually increased to determine resistance. It is the force of this weight which causes a con- 14 means of the tempering polyols described and can be measured with accuracy.

The following examples are included for a further understanding of the invention:

EXAMPLE I In the example of the following tables, polyol tempering compounds are added and coated by known methods in the concentrations shown to a medium speed photographic silver bromoiodide emulsion. The coatings of these examples are made on polyester (polyethylene terephthalate) support at 450 mg. silver/ft. and 1248 mg. gel/ft. for the medium speed silver bromoiodide emulsion. The films are exposed to an Eastman IB sensitometer, developed in Kodak DK-SO Developer for 5 minutes, fixed, washed and dried.

The higher values recorded for mushiness indicate an increase in wet jelly strength and a reduced mushiness. The lower values recorded in percent vertical swell likewise indicate a general firming up and resistance to mushiness of the emulsion layer when the polyol compounds are added.

A further indication of the effective tempering achieved by the use of these polyols according to the practice of the persent invention is shown by the improved toughness based on a reduced swell of the coatings after processing or immersion in high temperature baths.

TABLE L-SILVER BROMOIODIDE EMULSION One week incubation at 120 F. znd relative humidity Fresh Percent Conc., Mushiness vertical swell g./m Rel. Rel. distilled Addenda Ag speed 7 Fog speed 1 Fog Dev Fix H20 water Control 1. 22 02 204 1. 08 06 14 70 489 N-[tris(hydroxymethy1)-methyllhydroxyacetamlde. 50 107 1. 22 01 48 1. 32 05 18 122 76 359 N-[tris(hydroxymethyl)-met.hyl]methoxyacetamide 50 110 1. 24 01 1. 01 53 26 141 102 345 2.2,6,6-tetrarnethylolcyelohexanol 50 107 1. 15 01 316 1. 05 06 31 148 93 398 Nora-All coatings contain 0.235% mueochlorie acid based on the weight of gelatin in the emulsion layer plus a gelatin overcoat containing 0.34%

mucochloric acid based on the weight of gelatin.

tinuous disruption or ploughing of the colloid layer surface, which is reported.

The numerical values recorded for determining mushiness will be higher in those instances where the emulsion or layer tested is firm and tempered in contrast to low values where mushiness appears and little resistance to the stylus is offered. Further, vertical swell is numerically determined by relative percent values and where the layer containing the addenda is suitably hardened, a lower figure appears indicating still less relative swelling in water or aqueous processing solutions. These values are obtained by well-known methods employing a swellometer.

In Table I, it can be seen that significant increases in toughness with concurrent loss of mushiness are reported for the compounds useful in the practice of the persent invention.

The results set forth in all tables hereafter and obtained form the colloid-containing elements upon incubation are believed particularly significant since, at this time the effect of the chemical cross-linkage agents has substantially stabilized and the colloid strengthening is effected by EXAMPLE H The following example shows that similar good results are obtained in the practice of the present invention in various types of silver halide compositions including, radiographic emulsions. In particular, the tempering polyols are added to various radiographic coarse-grain emulsions to provide toughness and rigidity to the colloid-containing layers. The coatings in the following table are made on polyester support at a coverage of 473 mg. silver/ft. and 482 mg. gel./ft. As in Example 1, these films are exposed to an Eastman 1B sensitometer, developed in Kodak DK-SO developer for 5 minutes, fixed, washed and dried. Similar good results are obtained when a high speed roller transport system is employed using the X-OMAT processor (a trademark of the Eastman Kodak Company for its high speed roller transport type processor). In obtaining those values, the developer solutions contain glutaraldehyde, a chemical crosslinking type hardener as described more fully in Belgian Pat. 700,301 of Barnes et a1 issued Aug. 31, 1967.

TABLE II.RADIOGRAPHIC EMULSION (Fresh values) Kodak DK-50 Percent X-Omat Processor, Developer, vertical Coneentramushiness mushiness swell tion grams/ distilled mole Ag Dev. Fix H2O Dev. Fix H2O water Addenda:

Polyacrylamide 20 28 28 28 12 38 26 457 Poly(vinbl 3-hydroxyethylcarbarnylmethylcarbamate) 20 28 31 34 18 43 33 450 2-(Z-hydroxyethylemino)-2-(hydroxymethyl)-1,3-propanedi 29 36 42 16 49 41 377 57 6O 31 62 52 238 2-[bis(2-11ydroxyethyl)amlno-2-hydroxymethyD-l,3-propanedlol {10 46 58 57 26 66 52 373 20 46 61 60 30 68 53 271 Control 30 47 46 10 50 46 385 NOTES:

1. From the above it can be easily seen that by adding polyols in as little as one half of the concentration of the covering powering addenda used, significant increses in wet jelly strength as well as reduced mushiness and vertical swell in water are obtained. 2. From the following results it can be seen that both reduced vertical swell and significant improvement in tempering evidenced by decreased mushiness values by various combinations of polyol and covering power addenda are achieved.

Polyacrylamide 20..- 28 28 12 38 26 457 Polyacrylamide and 2-(2-hydroxyethylamino)-2-(hydroxymethyl)-1,3- {10 of each- 26 32 32 11 57 36 378 propanediol. 20 of cach 22 24 20 12 43 36 311 Poly(vinyl fi-hydroxyethylearbamylmethylearbamate) 20 of each 28 31 34 18 43 33 450 Poly(vinyl B-hydroxyethylearbamylmethylcarbamate) and 2-(2-hy- {10 18 31 34 9 38 31 387 droxyethylamino)2-(hydroxymethyl)-1,3-propanedlol. 20 of each 28 33 39 36 40 294 EXAMPLE III EXAMPLE IV In order to demonstrate the effective strengthening of 30 Similar good toughening results are obtained in gelatinthe all-gelatin system contained in the photographic elelatex systems in which these colloid combinations are temment obtained by adding the tempering polyols described pered by the representative polyols of the group described in the present invention, a procedure substantially as deherein. The photographic silver bromoiodide emulsions are scribed in Example I is employed with the following re- 3r as described in Example I both as to coating and processsults: 0 ing.

TABLE IIL-SILVER BROMOIODIDE EMULSION 1 1 wk. incubation Fresh 120 F/% RH Fresh mushiuess Conc.,

g./m. Rel. Rel. Addenda Ag speed 7 Fog speed 7 Fog Dev. Fix 1120 Control 1. l3 05 214 1.06 09 8 99 63 Poly(aery1amide 50 112 1 21 .06 234 1.12 08 4 38 38 Poly(acrylamide) 50 plus 204 1. 17 09 417 1. 04 14 12 51 44 2-(2-hydroxyethylamiuo-2-(hydroxymethyD-l,3-propanediol 25 Poly(vinyl 5-hydroxyethylcarbamylrnethylcarbamate) 50 118 1. 27 08 282 1.17 07 9 53 51 Poly(viny1 B-hydroxyethylcarbamylmethylearbamate) 50 p us 219 1. 20 09 436 0.98 21 15 52 46 2-(2-hydroxyethylamino)-2-(hydroxymethyl)-1,3-propanediol 25 1 All coatings contain mucochloric acid at 0.235% as a hardener based on the weight of gelatin in the emulsion layer plus a gelatin overcoat containing 0.34% mucochloric acid based on the weight of gelatin.

TABLE IV.GELATIN-LATEX 1 wk. incubation Fresh F/50% RH Fresh mushiness Cone,

g./m. Rel. Rel. Addenda Ag speed 7 Fog speed 1 Fog Dev. Fix H O Control 100 1.08 06 204 1. 05 .06 18 98 77 Polb(acrylamide) 50 112 1. 24 06 191 1. l9 07 8 29 26 Polb(vinyl fl-hydroxyethylcarbamylmethylcarbamate) 50 126 1. 21 06 263 1. 18 07 12 36 20 Polb(aerylau1ide) 50 plus 191 1. 18 06 389 1. 03 11 23 44 49 2-(2-hydroxyethylamino) 2-(hydroxymethyl)-1,3-prcpanediol 25 Poly(vinyl 18-hydroXyethylcarbamylmethylcarbamate) 50 us 193 1. 12 07 398 0. 99 16 30 00 51 2-(2-hydroxyethylamino)-2-(hydroxymethyl)-1,3-propanediol 25 1 2:1 gelatin-latex (copolylmethyl aerylate-3-acryloyloxypropanesulfonic acid, sodium salt -2-acetoacetoxyethyl methacrylate]. Norm-All coatings contain mucoehloiic acid at 235% based 011 the weight of gelatin in the emulsion layer plus a gelatin percoat containing 0.34% mueochioric acid based on the weight of gelatin.

17 18 EXAMPLE V EXAMPLE VI The results set forth in the following tables show that Several photographic elements are prepared by coating substantial rigidity and toughness is imparted by the polya light-sensitive composition comprising a medium speed ols representative of the group described in this invensilver bromoiodide photographic emulsion at a coverage tion to various emulsions such as those photographic emulof 450 mg./silver/ft. in gelatin binder at a coverage of sions to which covering power addenda are likewise add- 1248 mg./ft. on a polyethylene terephthalate film suped. The coating and processing of the photographic emulport. These films are exposed on an Eastman 1B sensisions are the same as those previously described in Extometer, developed in Kodak DK-SO developer, i.e. an ample I. elon-hydroquinone containing developer, for 5 minutes,

TABLE V.SILVER. BROMOIODIDE EMULSION 1 wk. incubation, Fresh, Mushiness in 0 Fresh 120 F./50% RH mushiness developer onc., g./rn. Rel. Rel. Incuba- Addenda Ag speed 7 Fog speed 7 Fog Fix H2O Fresh tion Control 100 l. 24 02 214 1. 11 08 117 86 6 14 Poly(acrylamide) 50 115 1. 30 02 200 1. 10 O8 47 51 6 12 Poly(vlnyl fl-hydroxyethylcarbamylmethylcarbamate) 50 120 1. 32 02 251 1.19 07 70 79 13 13 2-(Z-hydroxyethylamino)-2-(hydroxymethyl)-l,3-propane dinl 50 178 1. 18 02 148 108 6 25 2 [bis (2 hydroxyethyl) amino] 2 (hydroxyrnethyl) 1,3

propanedinl 50 174 1. 01 295 1. 02 12 144 00 5 23 P 01y) acrylam de 50 and l 178 1. 27 01 339 1. 04 11 70 67 14 2 (2 -hydroxyethylamlno)-2-diydroxyrnethyl)-1,3-propane- 30 I O Polyacryl mi and 148 1. 27 01 276 1.00 07 71 66 21 15 2 [bis(2 hydroxyethyDamino] 2 (hydroxymethyl) 1,3 prnnanarlinl 30 Po1y(vinyl B-hydroxyethylcarbamylmethylcarbamate) 50 and v 186 1. 32 02 407 1. 04 24 86 24 20 2(2 hydroxyethylamino) 2 (hydroxymethyl) 1,3 propanediol- 30 Poly(v'lnyl fi-hydroxyethylcarbamyhnethylcarbamate) 50 and 162 1. 30 02 302 1. 14 08 82 64 20 18 2 [bis(2 hydroxyethyl) amino] 2 (hydroxymethyl) 1,3

pmpnnnriinl 30 N own-All coatings contain mucochlon'c acid at 0.235% based on the weight oigelatinin the emulsion layer plus a gelatin overcoat containing 0.34% mucochloric acid based on the weight of gelatin.

followed by fixing, washing and drying. Sensitometric data and physical measurements are recorded as follows:

TABLE VI.A.SILVER BROMOIODIDE EMULSION 1 wk. incubation, Mushiness Fresh, Fresh 120 F./50% RH percent Cone, Developer, vertical g./m. Rel. Rel. fresh swell dist. Addenda Ag speed 7 Fog speed 7 Fog incubation Fix H2O water Control 100 1. 10 09 219 1. 04 06 18/36 111 398 Poly(acry1amide) 50 107 1. 18 08 191 1. 07 06 12/22 56 59 412 N-[tris(hbdroxymethyhmethyll omethoxybenzamide 50 107 1. 09 07 240 1. 06 06 12/34 80 418 2-acrylamido-2-hydroxymethyl-l 3-propanediol. 50 89 1. 06 07 191 1. 00 06 21/60 118 79 346 2,2,6,6-tetramethyloleyclohexano 50 118 1. 10 07 389 1. 00 .06 28/64 112 90 318 Trimethylolethane 50 1. 02 07 339 98 06 36/78 125 94 287 Poly(acrylamide) 50 and 105 1. 20 .08 200 1 08 .06 9/20 46 53 418 2,2,6,6-tetramethyloleyclohexanol 25 Poly(acrylarnide) 50 and 105 1 19 .07 178 1 08 .06 12/25 57 50 400 1,3-pmpanedinl 25 Poly(acrylamide) 50 and 118 1. 18 07 234 1. 05 00 8/19 50 42 435 methyll-o-methoxybenzamide 25 Poly(acrylamide) 50 Y and 1. 16 07 219 1. 11 06 15/30 65 65 369 Trimethylolethanc 25 1 All coatings contain mucochloric acid at 0.235% based on the weight of gelatin in the emulsion layer plus a gelatin overcoat containing 0.34% mucochloiic acid based on the weight of gelatin.

TABLE VI-B-SILVER BROMOIODIDE EMULSION 1 Fresh Percent Conc.. Mushiness vertical g./m. Rel. swell dist. Addenda Ag. speed -y Fog Dev. Fix H2O water 13? 1'53 '81 t2 132 .33 2- 2-h dro eth lamino -2- 0 met l-1,3- ro ane 'o 404 s2 is it? a a a; as 2-bis 2-h drox eth lamino -2- h drox meth l-1,3-propane o 69 I D o u (y y y 50 151 1.11 .01 58 187 136 311 Butyl tri (hydroxymethyl) acetate 50 85 1. 12 01 39 172 116 293 1,6-hexanediamine di[tris(hydroxymethyl) acetic acid addition salt] 20 148 1. 12 01 7 100 74 462 Tris(hydroxymethyl)methyl amine glyeollc acid addition salt. 25 91 1. 16 01 30 165 107 413 D0 50 82 1. 22 32 148 328 1 All of the coatings contained 0.235% mucochlon'c acid based on the weight of gelatin in the emulsion layer plus a gelatin overcoat containing 0.34% mucochloric acid based on the weight of gelatin.

The tougheners in accordance with our invention have shown themselves to be useful in color photography such as in photographic emulsions in which color couplers have been incorporated. The use of these polyols results in layer toughness with little adverse sensitometric effects used in levels producing satisfactory tempering in contrast with some of the crosslinking types of gelatin hardeners. No adverse effects upon dye hue or stability of the emulsion has been observed. For instance, in a photographic product in which coatings of the following structure were applied to a support these tempering agents have been used with good effect:

Layer 6Gelatin layer. Layer 5Red-sensitive silver chlorobromide gelatin consisting of 90 mole percent bromide and a phenolic cyan 1 The polyols in accordance with our invention can be used in all six of the layers of the product or they can be used in the emulsion compositions with other hardeners being used in the gelatin layers if desired.

EXAMPLE VII In a manner similar to that described in the foregoing example, additional photographic examples are prepared by coating onto a polyethylene terephthalate film support a coarse grain silver bromoiodide gelatin emulsion having 6 mole percent iodide and the remainder, bromide. Silver bromoiodide covering is effected at 459 mg. silver per square foot and gelatin coverage at 1037 mg. per square foot. The following stable records various swell measurements and demonstrates that the toughening compounds useful in the practice of the present invention appear to differ in their mechanism of action when compared to known crosslinking compounds, the latter exhibiting a swell value of substantially less than 500%.

TAB LE VII Percent Concentration l Swell Control. 040

Mucochloric acid Formaldehyde Bis (lginylsulfonylmethyl) ether Compound present Do 4, 4-dimetl1yloloxazolidonc 2, 2, 5, ti-tetramethylol eyclopcntanel 1 Concentration described as percent compound by weight present per total weight of gelatin.

EXAMPLE VIII As in Example VI, still other photographic examples are prepared in the same manner as described. Tables VIIIA and VIIIB which follow record the fresh and incubated sensitometric values along with the corresponding mushiness in various processing solutions. The percent swell determined in fresh examples and after incubation, clearly demonstrates the superior properties of the compounds useful in the practice of this invention.

TABLE VIIIA relative humidity Fresh (incubation) Mushiness Percent Level (fresh/incubation) swell (g./Ag Rel Rel. (fresh/ Compound present mole) speed 7 Fog speed 7 Fog Dev. Fix Wash incubation) Control 109 1. 18 0.09 191 1. 11 0.08 10/24 96/ 138 67/ 99 540/367 4,4-bis(hydroxymethyl)-2-0xaz0l011e 97 1. 17 0. 07 282 1. 09 0. 08 17/56 104/200+ 154 443/278 Poly(acrylamide) 50 1. 30 0. 08 204 1. 13 0. 08 5/ 12 41 9 46/48 552/403 2,2,6,6-tctran1cthylol eyclol1exauol..- 25 112 1. 12 0 07 251 1. 11 0.08 16/35 120/148 88/112 468/355 2.2,6,6-tetramethyl0l cyclohexanoL 50 1. 13 0. 06 295 1. 11 0.08 21/ 47 128/134 101/131 430/ 314 2,2,6,6-tetramethylol cyclol1exanol, 25

plus 107 1.17 0 O7 257 1. 11 0.07 12/23 76/98 70/82 490/373 Poly-acrylamide 25 NOTE.-All coatings contain 0.235% mueochloric acid based on the weight of gelatin in the emulsion layer plus a gelatin overcoat containing 0.34%

mueochloric acid based on the weight of gelatm.

TABLE VIII-B relative humidity Fresh (incubation) Mushiness Percent Level (fresh/incubation) swell (gt/Ag Re]. Re]. (f'rcsh/ Compound present mole) speed 7 Fog speed 7 Fog Dev. Fix Wash incubation) Control 100 1. 02 0.06 118 1. 01 0. 06 18/32 92/123 68/86 500/309 Poly[2-acrylamidoethyltris(hydroxymethyl) acetate 18. 8 87 1. 10 0. 06 100 1. 09 0. 06 14/24 62/80 56/64 528/356 2,2,5,5-tetramcthylolcyclopentauol 25. 0 179 0. 88 0. 10 159 0.93 0. 07 16/43 114/138 52/94 443/280 2,5,5-tctraliydroxymethylcyclopcntano11c 40. 8 0. 91 0. 06 112 0. 98 0.07 20/40 112/138 58/102 442/291 2,2-dinietlloliudauonc 0 141 0. 93 0.05 148 1. 01 0 05 34/52 136/158 70/108 378/273 D0 50. 0 162 0. 89 0.07 174 0. 97 0. 05 64/88 144/181 87/163 309/222 l,1,3.3-tetramethylol-Z-decalone 25. 9 110 0. 84 0. 06 132 0. 88 0.06 54/77 152/157 96/116 229/175 Do 50.0 110 0.71 0.08 129 0.87 0.05 76/99 156/148 97/112 86/77 N,N-[tris(hydroxymethyDmethyl urea 21. 2 209 1. 00 0. 08 1.00 0. 07 12/23 100/124 62/91 495/333 N ,N-[tris(hydroxymeth l)metl1yl urea 21. 2

plus 20-1 1 00 0.08 191 1.05 0.06 8/21 56/73 56/65 533/356 Polyacrylannde 25. O N-[tris(hydroxymethylhncthyl]tris(hydroxymethyDacet-amide 15. 2

plus 115 1. 19 0. 06 97 1. 20 0. 00 7/22 52/69 52/65 509/334 Polyacrylamide 25. 0

Norm-All coatings contain 0.235% mucochloric acid based on the weight of gelatin in the emulsion layer plus a gelatin overcoat containing 0.34%

mueochloric acid based on the weight of gelatin.

wherein R is phenyl or substituted phenyl selected from the group consisting of o-methoxyphenyl, 2,4-dichlorophenyl, p-tolyl, p-bromophenyl, 2,4-xylyl, p-acetylphenyl and p-biphenylyl; alkyl group of from 1 to 8 carbon atoms; substituted alkyl selected from the group consisting of hydroxymethyl, methoxymethyl, hydroxyethyl, 3-chloropropyl and benzyl or alkenyl; p is or 1; m is 0, 1 or 2; and n is l or 2; the sum of m and n being at most 3; or

wherein R is alkyl group of from 1 to 8 carbon atoms, a hydrogen atom, an alkali metal or the atoms necessary to complete an ammonium salt group; or

wherein D is the atoms needed to complete a 5 or 6 membered carbocyclic ring; and taken separately, R is hydro gen and R is hydroxy, or taken together R; with R represents an oxo-group or iv E noon f 2 HOCI-Ia 0]. (V) E) o I onion onion said tempering compound is present in said element in admixture with said hydrophilic colloid in an .amount equal to from about 5 to about 50 weight percent of said hydrophilic colloid.

2. The element of claim 1 in which said tempering compound is present in combination with said silver halide or a layer adjacent thereto.

3. The element of claim 1 in which said silver halide is combined with the colloid to be tempered.

4 The element of claim 2 in which said silver halide is present as an emulsion layer.

5. The element of claim 1 further comprising colorforming couplers.

*6. A process for tempering a photographic silver halide element comprising a support, a hydrophilic colloid layer chemically hardened by reaction with a crosslinking agent which process comprises incorporating into said layer or in a layer adjacent thereto a tempering concentration of a compound having the structural formula:

wherein R is phenyl, or substituted phenyl selected from the group consisting of o-methoxyphenyl, 2,4-dichlorophenyl, p-tolyl, p-bromophenyl, 2,4-xylyl, p-acetylphenyl, p-biphenylyl; substituted alkyl selected from the group consisting of hydroxymethyl, methoxymethyl, hydroxy ethyl, 3-chloropropyl and benzyl; or alkenyl; p is 0 or 1; m is 0, 1 or 2; and n is l or 2; the sum of m and n being at most 3; or

wherein R is an alkyl group of (from 1 to .8 carbon atoms, a hydrogen atom, an alkali metal or the atoms necessary to complete an ammonium salt group; or

wherein D is the atoms needed to complete a 5 or 6 membered carbocyclic ring; and taken separately R is hydrogen and R is hydroxy, or taken together R and R represents an oxo-group or V) 0 ll noon I onion mono said tempering concentration is in an amount equal to from about 5 to about 50 weight percent of said hydrophilic colloid.

7. The element of claim 1 in which said hydrophilic I colloid is gelatin.

8. The element of claim 1 which further comprises a substantially dried latex resulting from the polymerization of a substantially water insoluble alkyl ester of an ethylenically unsaturated acid.

9. The element of claim 1 in which said temmpering compound is:

2-(Z-hydroxyethylamino)-2-(hydroxymethyl)-1,3-

propanediol; or

2t[bis(2-hydroxyethyl)amino]-2-(hydroxymethyl)-1,3-

propanediol; or

2,2,6,6-tetramethylolcyclohexanol; or

2,2,5,5-tetramethylolcyclopentanol; or

1,1,3,3-tetramethylol-2-decalone; or

2,2-dimethylolindanone.

10. A photographic silver halide hydrophilic chemically hardened colloid emulsion containing a tempering concentration of a compound having the structural formula:

0 R-e0-(ii-G(CH2OH)3 wherein R is alkyl group of from 1 to 8 carbon atoms,

23 a hydrogen atom, an alkali metal or the atoms necessary to complete an ammonium salt group; or

(III) R2 R3 (HOCHzh-Q 9(CH2OH)? wherein D is the atoms needed to complete a 5 or 6 membered carbocyelic ring; and taken separately, R is hydrogen and R is hydroxy, or taken together R with R represents an oxo-group or (1V) 0 ll HN/ 11oom noon;

11. The emmulsion of claim 10 in which said hydrophilic colloid commprises gelatin.

12. A layer derived from a chemically hardened and dried combination of a gelatin sol and a latex resulting from the polymerization of a substantially water-insolubie alkyl ester of an ethylenically unsaturated acid and containing coarse-grain silver halide; said latex and gelatin combination tempered by an elfective tempering concentration of a compound having the formula of claim 1 said effective concentration is from about 5 to about 50 weight percent, based on the weight of hydrophilic colloid in said layer.

References Cited UNITED STATES PATENTS 3,595,663 7/1971 Emmi 96l ll 2,494,055 l/l950 Orkin 96l ll 3,453,109 7/1969 Lee 96-1 ll 2,629,659 2/1953 Mueller 96l 11 NORMAN G. TORCHIN, Primary Examiner W. H. LOUIE, JR., Assistant Examiner US Cl. X.R.

260ll7; 106-l25; 96-94