GB2070267A - Light-sensitive silver halide photographic material - Google Patents

Abstract

Problems such as undesirable adhesiveness associated with the outermost, protective, layers of photographic materials comprising a support carrying at least one layer of a silver halide emulsion can be overcome by using an outermost layer comprising colloidal silica having an average grain diameter of less than 100 m<0> and an organic fluoro compound.

Description

SPECIFICATION Light-sensitive silver halide photographic material The present invention relates to the improvement of a silver halide photographic material in the physical characteristics thereof, especially in the surface property.

In general, silver halide photosensitive materials have a support provided thereon with at least one silver halide emulsion layer and a surface layer and a backing layer of an aqueous colloidal material such as gelatin. Therefore, under the condition of a high temperature with high humidity, adhesion between the surface and backing layers of the materials is caused during the manufacture, exposure, processing or storage of the material, which may sometimes bring about various disadvantages.

In order to remove such disadvantages, attempts have heretofore been made to reduce the adhesiveness by way of matting the surface to decrease the contact area in such a manner that fine grains of inorganic materials such as silica, titanium oxide, magnesium oxide and the like, or organic materials such as polymethyl methacrylate, cellulose acetate propionate and the like are incorporated into the surface layer. However, there have been such drawbacks that the incorporation of these materials sometimes causes the coating liquid to produce solid lumps therein, thereby hindering a uniform coating thereof, or deteriorating the transparency and sharpness of photographic images.

As the surface matting effect, some improvements are recognized in the antistatic besides the reduction of adhesiveness and disappearance of Newton ring. However, the occurrence of the surface electrostatic, one of the important problems of surface characteristics, cannot be satisfactorily solved by such a measure as the matting only. For the improvement In the antistatic, various antistatic agents have so far been attempted, and the patents therefor are too numerous to be mentioned, but there have been many cases where the addition of such antistatic agents for the improvement in the antistatic has brought about troubles in the coating process.

To avoid such troubles, various surfactants have been further devised and attempted. In most cases, however, the surfactant and the antistatic agent cancel the effects each other, so that any satisfactory results have not been obtained. In connection with this, Belgian Patent 742,680 describes that such cancellation can be well reduced or removed by the use of fluoride surfactants. Further, U.S. Patent 3,754,942 and Japanese Patent O.P.I. Publication No.

7781/1971 describe that the cancellation being latent between the surfactant and the antistatic agent can be restrained to improve the antistatic by incorporating water-insoluble particles in the diameter of from 1 to 10 11 in the amount of from 10 to 100 mg/m2 into the surface layer.

Meanwhile, the method for incorporating water-insoluble particles, which has been generally employed, is prone to cause the photographic material to be less transparent, British Patent 692,592 describes that the disadvantage is reduced by incorporating colloidal silica into the surface layer; and tJ.S. Patent 3,519,379 describes that devitrification may be prevented by incorporating into the surface layer gelatin, hydrophilic colloid other than gelatin and colloidal silica in the amount of from 5 to 20% of the gelatin, thereby resulting in the improvement in the abrasion resistance as a secondary effect.

As has been described above, one proposal after another for the improvement in physical characteristics of photographic light-sensitive materials. because of the complicatedly latent factors, creates new one fault after another, thus causing an endless vicious circle.

We have studied for the improvement in the surface property and confirmed that the adhesiveness as well as transparency can be effectively improved by incorporating colloidal silica into the surface layer, but we have found such critical defects that the incorporation of colloidal silica into the surface layer accelerates the deterioration with brittleness of photographic materials. Such defects are deathblow defects to the photogråphic industry; especially in the case of appiyin9 an abruptiy deformational impact to a photographic material at a low humidity, for example, an abruptly high speed film winding and the like in a motor drive system camera causes a tear of a film loaded therein, whereby the material results in losing its value as a commodity.

In view of this, the object of the present invention is to provide a light-sensitive silver halide photographic materia; which is improved in the surface characteristics relating to adhesionresistance and transparency, and which will not become brittle as stored for a long time.

The photographic material of the present invention comprises colloidal silica having the average grain diameter of less than 100 mr and an organic fluoro compound in the outermost layer of a pnotographic material.

And in the preferable embodiment, the photographic material further contains a polyoxyethy iene series compound together with the colloidal silica and an organic fluoro compound.

Further, it has been also found that the present invention permits the use of either the colloidal silica produced by the wet method or the one by the dry method, but the former gives better results.

What has been further found as a result of the study is that among the organic fluoro compounds usable in this invention the anionic series ones give much better results.

In addition, the mechanism of the deterioration with brittleness in time by being mixed in with colloidal silica only (i.e. without at least an organic fluoro compound) is still not clear, but we, in the light of various experimental facts consider that it is the result of the production of secondary particles or network structure in course of time following an interaction among the colloidal silica particles because of the hydrogen coupling by the cyanol group on silicic acid. On the other hand, an organic fluoro compound and/or polyoxyethylene series compound are thought to hinder the interaction among the colloidal silica grains or as a loose coupling chain to interfere among the grains.

The respective elements used in the present invention are illustrated in detail below: The colloidal silica usable in the present invention is of the average grain diameter of less than 100 my and preferably not less than 1 m/L, and may contain silicon oxide as the principal constituent thereof and alumina or sodium aluminate as the minor constituent thereof, and also as a stabilizer. such inorganic salts as sodium hydroxide, potassium hydroxide, ammonia and the like. and such an organic base as tetramethyl ammonium ion. These colloidal silicas are described in detail in the Surface and Colloid Science edited by Egon Matijievic, vol. 6, pp 3-100 (1973).

The colloidal silicas used in the present invention are classified as ones by dry method and ones by wet method according to the manufacturing methods. The dry method herein mentioned corresponds to what is called "powdered silica in low concentration and minute gel dispersed" in the foregoing Surface and Colloid Science, vol. 6 pp 77-100 (1973), which is one porous produced by the high temperature vapor phase hydrolysis with the use of SiCI4 as the starting material The wet method herein mentioned corresponds to the commercially available silica sol described in the foregoing documents which exists In the form of a sol and is one that is produced by the neutralization by an acid with the use of sodium silicate as the starting material and is stabilized by an alkali agent such as NaOH, ammonia and the like, The purity of the product is 30-50% by weight of silica and the average particle diameter thereof is 5-50 my.

One produced by the dry method is marketed in the product name of Cab-O-Sil EH-5H-5 from Cabot, in the name of Siloid Over 20 grades from Davidson Div W. R. Grace, in the names Santocel-62 and Santocel-FRC from Monsanto. and in the names Aerosil-1 30, 200 and 300 from Degussa Inc An examples of the colloidal silica manufactured by the dry method, there may be cited Ludox-AM, Ludox-AS and the like from E. I. DuPont, Syton C-30, C-40, etc. from Monsanto.

Snowtex 20, Snowtex C, etc. from Nissan Chemical Co., Ltd. (Japan), and Nalcoag-1030, 1034A, etc. from Nalco Chem Co.

The preferred colloidal silica usable in the present invention is one that is produced by the dry method and of the average particle diameter of less than 50 mjil is effective in adhesion resistance. The preferred using amount of it is from 0 05 to 2.0, most preferably from 0.1 to 0.5 in proporton by dry weight to the amount of the gelatin used as the binder for the outermost layer.

Secondly, the organic fluoro compound usable in the present invention is an organic fluoro compound surfactant which includes chain or cyclic compounds containing at least three flurine atoms and at least three carbon atoms, which may be any of cationic, nonionic, anionic and betainic compounds, which are per se well known to the person skilled in the photographic art.

The preferable examples thereof are those described in the following formula: (Cf)-(Y)" (F-l) In the formula C, is a fluorine substituted n-valent aliphatic hydrocarbon group containing at least three fluorine atoms and at least three carbon atoms,

wherein M is hydrogen, alkaline metal, alkaline earth metal, quaternary ammonium base, or hydrocarbon radical having 1 to 18 carbon atoms.

-(-AO-)- is polyoxyethylene, polyoxypropylene or poly(oxyethylene and oxypropylene) each of which having 2 to 100 polymerization degree, R is hydrogen alkylene having 1 to 18 carbon atoms or arylene, R,, R2, R3, R4, R5, R6, R7 and R8 are each alkyl or hydroxyalkyl having 1 to 4 carbon atoms, R9 and Rro are each hydrogen or alkyl or hydroxy alkyl having 1 to 4 carbon atoms, X is halogen or R-O-SO2-O, Z is atomic group forming 5 or 6 membered heterocyclic group containing nitrogen oxygen, or sulfur, D is alkylene having 1 to 5 carbon atoms, n is 1 or 2.

In the more preferred embodiment of the present invention, the organic fluoro compound is selected from those described in the formula

wherein Cf, R8, X(- and D have same meaning as defined in the formula (F-l), A, is -SO3M or -O(CH2CH2O)r-B, (B, is hydrogen, -COCH2CH2C0OM or -COCH = CH-COOM, M has the same meaning as defined in the formula (F-l), r is 1 to 100), n' and n2 are each 1 to 5, R", R,2 and R13 are each hydrogen or alkyl having 1 to 4 carbon atoms, p is 1 to 10, q is 1 to 6.

Typical examples of the organic fluoro compounds usable in the present invention are described in, e.g., U.S. Patents 3,589,906, 3,666,478, 3,754,924, 3,775,126 and 3,850,640, British Patent 1,330,356, and Japanese Patent O.P.I. Publication No.

106419/1976.

The following are typical examples of the organic fluoro compounds usable in this invention:

wherein SO3K is o-, m- or p-positioned, or a mixture of them.

wherein SO3Na is o-. m- or po-positioned, or a mixture of them.

F-(19) CF3(CF2)7-SO3K F-(20) CF3(CF2) 11-CH2-SO3NA F-(21) CF3 (CF2) 6-COO- (CH2)3-SO3Na F-(22) H(CF2) 6-CH2-O-(CH2)3 503Na

F-(34) CF3-(CF2)-COO-(CH2CH2-O-)CH3 F-(35) H-(CF2)10CH2OH F-(36) H-(CF2)6-CH2OH

wherein SO3Na is in the 4th of 5th position, or a mixture of them.

F-(5a) H(CF2)6-CH2O+CH2CH2O)+lOH F-(59) H-(CF2) 6-cH2o+CH2cH2o#20H F-(6O) H-(CF2)4-CH2CH2O)5H (CF2)-CH2O+CH2CH2O)5H

Besides the above compounds, there are marketed by Asahi Glass Co., Ltd. fluorine series surfactants, etc. in the names of Surflon S-111, S-112, S-113, S-121, S-131 and S-145.

The most preferred organic fluoro compounds in the present invention are of anionic series. The adding amount of the organic fluoro compound is from 0.1 to 500 mg, preferably from 1 to 200 mg. per m2 of the outermost layer to be coated.

The proportion of the adding amount of the colloidal silica and organic fluoro compound used in the present invention is from 5:1 to 100:1, most preferably from 10:1 to 50:1.

Thirdly, the polyoxyethylene series compounds used in the present invention are represented by the following general formulas from EO-(1) to EO-(17):

wherein R' represents an alkyl having from 1 to 18 carbon atoms, R2 represents hydrogen or an alkyl having from 1 to 18 carbon atoms, provided that R' is an alkyl of from 1 to 7 carbon atoms when R2 is hydrogen, M represents cations, and n is an integer of from 1 to 50.

wherein 1 + n = 10 to 80, provided that either 1 or n may be zero, and m = 5 to 200.

EO-(3) BCOO(CH2CH20)#H wherein R is an alkyl, preferably the alkyl having from 3 to 21 carbon atoms, and n is an integer of from 5 to 135.

Eo-(4) R'COO(CH2CH20)nOCR2 wherein R' and R2 represent alkyls which may be either the same or different, the preferred totaled number of carbon atoms of R' and R2 is from 6 to 34, and n is an integer of from 5 to 100.

EO-(5) RO(CH2CH2O)nH wherein R is an alkyl, preferably having from 4 to 22 carbon atoms, which may be substituted by fluorine, and n is an integer of from 3 to 50.

EO-(6)

wherein R' and R2 each is hydrogen or an alkyl (preferably the alkyl having from 1 to 9 carbon atoms), which may be substituted by fluorine, and n is an integer of from 3 to 150.

wherein R' and R2 each is hydrogen or an alkyl (preferably the alkyl having from 1 to 9 carbon atoms), which may be either the same or different, and m is an integer of from 2 to 50, while n is from 3 to 100.

EO-(8) R'O(CH2C:H20)nR2 wherein R' and R2 may be either the same or different alkyl, whose totaled number of carbon atoms is from 8 to 36, and n is an intefer of from 5 to 100.

wherein R is an alkyl, preferably the alkyl having from 8 to 18 carbon atoms, and m + n = from 3 to 100.

wherein R is an alkyl, preferably the alkyl having from 7 to 17 carbon atoms, and 1 +m+n=from 5to 100.

wherein R is a alkyl, preferably the alkyl having from 4 to 22 carbon atoms, and m = from 1 to 20, while n = from 5 to 100.

EO-(12) RS(CH2CH20)#H wherein R is an alkyl, preferably the alkyl having from 4 to 18 carbon atoms, and n = from 3 to 50.

wherein m + n = from 5 to 50

wherein R is an alkyl, preferably the alkyl having from 4 to 17 carbon atoms, and m + n = from 3 to 100.

wherein R is an alkyl, preferably the alkyl having from 7 to 18 carbon atoms, and m + n = from 5 to 50.

wherein R is an alkyl, preferably the alkyl having from 7 to 18 carbon atoms, and n = from 5 to 100.

The adding amount of the polyoxyethylene compound to that of the colloidal silica is in the proportion by weight of from 1:1 to 1:50, preferably from 1:10 to 1:30.

The above are the illustration in detail about the conspicuous elements of the present invention. Subsequently the elements used in the present invention are illustrated below relative to the composition of silver halide photographic light-sensitive materials.

Fourthly, a matting agent is permitted to be used when necessary in the present invention.

The matting agents usable in the present invention include such inorganic materials as silica, magnesium oxide, titanium dioxide, calcium carbonate and the like, and such organic materials as polymethyl methacrylate, cellulose acetate propionate, or alkali-soluble porous polymer particles comprising acrylic acid and methyl acrylate such as described in Japanese Patent O.P.l.

Publication No. 135958/1976. The preferred particle size of these agents is from 0,5it to 20y, most preferably from 1y to 1 OIL. In the most preferred embodiments of the present invention, the matting agent is polymethyl methacrylate or silica in the average particle diameter of from 1 to 61l. The non-light-sensitive hydrophilic collqidal layer of the present invention may be provided on the silver halide emulsion layer and/or on the non-silver halide emulsion side of a silver halide photographic light-sensitive material.For example, in the case where the support is provided on both sides thereof with silver halide emulsion layers, both the layers may be provided thereon with the non-light-sensitive hydrophilic colloidal layers, while in the case where a silver halide emulsion layer is present on one side of the support, the non-light-sensitive hydrophilic colloidal layer may optionally be provided on the backing side and/or on the emulsion layer.

The thickness of the non-light-sensitive hydrophilic colloidal layer of the present invention is suitably normally in the range from 0.1 to S,IL, most preferably from 0.5 to 3y.

Fifthly, the present invention allows the incorporation of oil drops.

The light-sensitive material produced in accordance with the present invention is provided on the support thereof with at least one silver halide emulsion layer, and for the silver halide emulsion layer as well as the support and auxiliary layers such as antihalation layer, filter layer, interlayer, subbing layer, and the like, all known materials may be used.

EXAMPLE 1 A high-speed silver iodobromide (containing 2 mol% silver iodide) emulsion for X-ray use containing gelatin in the amount of 60 g. per mol of the silver halide thereof was prepared, and then to the emulsion were added 4-hydroxy-methyl-1,3,3a,7-tetrazaindene as a stabilizer, saponin as a coating aid, and mucochloric acid as a hardener. The resulting emulsion was coated simultaneously superposedly with each of the protective layer compositions shown in Table 1 by the slide hopper method at the coating speed of 50 m/minute on a subbed polyester film support so that they constitute in the order of the film support, emulsion and protective layer, thereby obtaining samples (1)-(5).The dried thickness of the emulsions of the coated samples was 3ji, while that of the protective layers was 1 #5IL Table 1 Protective Layer Compositions Sample (1) Sample (2) Sample (3) Sample (4) Sample (5) Binder 2.0g./m2 Coating aid 0.01 g.m2 Colloidal silica 0.3g/m2 O.3g/m2 Anionic organic fluoro compound 10mg/m2 10mg/m2 Cationic organic fluoro compound 10mg/m2 10mg/m2 Colloidal silica . . . Ludox AM (grain diameter: 13-14 my) Anionic organic fluoro compound: Compound F-(23) Cationic organic fluoro compound: Compound F-(39) A pair of test pieces in 5 square centimeter size were cut out from each of these dried samples No. 1-No. 5, and were allowed to stand so as not to come into contact with each other in the atmosphere conditioned at 40 C, with 80%RH (wherein RH represents relative humidity; to be repeated in the following). The respective pairs were then placed with their protective layers brought face to face into contact with each other, loaded thereon with weight of 800 g. and stored in the air conditioned at 40 C. with 65%RH.Afterward the pairs were peeled apart and the area of the adhered portion of each sample was measured to evaluate the degree of adhesiveness. The results are shown in Table 2. The evaluation criteria are as follows: The area of adhered portion ranked A: 0-20% The area of adhered portion ranged B: 21-40% The area of adhered portion ranked C: 41-60% The area of adhered portion ranked D: 61-80% The area of adhered portion ranked E: 81 % and more Further, evaluation of the brittleness was made through the measurements using such a wedge type tester as described in the P.S.E., vol. 1 p.63 (1957) on a pair of test pieces in 1 X 80 cm size cut out from each of the samples No. 1-No. 5, one group of which was allowed to stand over a period of three days in the atmosphere conditioned at 23"C. with 20%RH to be regarded as non-aged group, and the other group os which was allowed to stand over a period of 14 days in the air conditioned at 40"C. with 65%RH to be regarded as aged group. The results of the measurements are shown in Table 2, wherein the brittleness is indicated in terms of torn length in mm; the longer the torn length the larger the brittleness.

Table 2 Sample No. 1 2 3 4 5 Evaluation on adhesiveness B C C A A Non-aged Brittleness test (torn length) 25 21 23 22 26 Aged Evaluation on adhesiveness B C C A A 40"C./65%RH Brittleness test 14 days (torn length) 59 25 21 32 38 The comparison of samples No. 1-No. 5 shows that the method of the present invention (samples No. 4 and No. 5) are superior in the adhesiveness and significantly improved in the brittleness as compared to the others. In comparison of sample No. 4, containing an anionic organic fluoro compound with sample No. 5, containing a cationic organic fluoro compound, the former is better improved in the brittleness in aging.

EXAMPLE 2 The following blue-sensitive emulsion and each of the protective layer compositions shown in Table 3 were superposedly simultaneously coated at the speed of 80 meters per minute by the slide hopper method on a subbed cellulose triacetate film support in the order of the support, blue-sensitive emulsion layer and protective layer.

The blue-sensitive emulsion layer used: a blue sensitive silver iodobromide emulsion (containing 7 mol% silver iodide) containing gelatin in the amount of 300 g. per mol of the silver halide thereof, as an yellow coupler, a-pivaloyl-a-(1 -benzyl-2,4-dioxyimidazoline-3-yl-2-chlorn-S [ 7-(2,4- tert-amylphenoxy) butylamidejacetanilide in the amount of 2.5 X 10-2 mol, and as a hardener 1 ,2-bis(vinylsulfonyl)ethane.

Table 3 Protective Layer Compositions Sample No. G6 Q7 Gelatin (g/m2) 1.5g/m2 Mating agent (g/m2) O.02g/m2 (1) (2) (3) Colloidal - O.Sg/m2 ~ 0.59/m2 O.Sg/m2 silica (g/m2) Organic fluoro (4) compound 1 ~ 15mg/m2 (mg/m2) Sliding agent (5) (g/m2) O.1g/m2 Hardener 1,2-bis(vinyl sulfonyl)ethane Note: (1) Silica in the average grain diameter of 3y (2) Ludox-AM (grain diameter: 13-14 m#) (3) Aerosil-200 (4) Exemplified F-(24) (5) One having the formula: CH2-OOC-nC11 H23 CH-OOC-nC11 H23 CH2-OOC-nC11 H22 The thickness of the protective layer was 1.1 ju.

Evaluation was made on both the adhesiveness and brittleness of samples No. 6-No. 10 in the same manner as in Example 1.

A pair of test pieces in 3.5 x 14 cm size were cut out from each of samples No. 6--No. 10, and one group of the samples was allowed to stand unexposed in the atmosphere conditioned at 5O'C. with 65% RH over a period of 14 days, while the other group was placed in the air conditioned at 23 C. with 55% RH (regarded as non-aged samples). Afterward, both the groups of samples were processed in accordance with the following processing and then dried. The resulting samples were measured on the turbidity thereof by means of a turbidimeter to obtain the data on their degrees of devitrification; the higher the turbidity the larger the degree of devitrification of the sample.

Processing steps Processing period Color developing 3 min. 15 sec.

Bleaching 6 min. 30 sec.

Washing 3 min. 15 sec.

Fixing 6 min. 30 sec.

Washing 3 min. 1 5 sec.

Stabilizing 1 min. 30 sec.

The liquid compositions used in the above processings are as follows: Color developer composition: 4-amino-3-methyl-NOethyl-N (p-hydroxyethyl)-aniline sulfate 4.75 g.

Anhydrous sodium sulfite 20.0 g.

Hydroxylamine 1/1 sulfate 37.5 g.

Anhydrous potassium carbonate 37.5 g.

Sodium bromide 1.3 g.

Trisodium nitrilotriacetate, monohydrated 2.5 g.

Potassium hydroxide 1.0 g.

Water to make 1 liter, whose pH is controlled 10.0 Bleacher composition: Ammonium salt of iron ethylene diaminetetraacetate 100.0 g Diammonium salt of ethylene diaminetetraacetate 10.0 g.

Ammonium bromide 150.0 g.

Glacial acetic acid 10.0 g.

Water to make 1 liter, whose pH is controlled 6.0 Fixer composition: 50% aqueous ammonium thiosulfate 162 ml Anhydrous sodium sulfite 12.4 g.

Water to make 1 liter, whose pH is controlled 6.5 Stabilizer composition: 37% aqueous formalin solution 5.0 ml.

Koniducks (manufactured by Konishiroku Photo Ind. Co., Ltd.) 7.5 g.

Water to make 1 liter The aged samples and the non-aged samples (control) were measured on their densities by means of a turbidimeter manufactured by Nippon Seimitsu Kogaku Co., Ltd.

Table 4 Test results Sample No. Q6 Q7 ~ 09 ~ Evaluation on adhesiveness C B B A A Brittleness test Non-aged (torn length in mm) 28 32 29 31 30 Degree of devitrification (turbidity %) 15 18 13 19 17 Aged Evaluation on adhesiveness C C B A A 40 C/65%RH Brittleness test 14 days (torn length in mm) 33 63 32 43 39 As seen from Table 4, No. 9 and No. 10, the light-sensitive materials of the present invention are found out to be improved and excellent in the antiadhesion and antibrittleness in aging as compared to No. 7 with a colloidal silica only added to the protective layer and No. 8 with an organic fluoro compound only added.

Further, in comparison of No. 9 with No. 10, the colloidal silica produced bathe dry method is found out to give better results relating to the brittleness in aging than that by the wet method, but in the adhesiveness and the degree of devitrification there was little difference between them.

EXAMPLE 3 A subbed triacetate film base was coated thereon with the following layers in the order described below, starting from the base: First layer: An antihalation layer containing black colloidal silver (dried thickness: 1y) Second layer: A red-sensitive silver iodobromide (containing 8 mol% silver iodide) emulsion layer (dried thickness: 6IL) containing a cyan coupler, l-hydroxy-N{y-2,4 naphthoamide in the amount of 6.8 X 10-2 mol per mol of the silver halide; a colored coupler, 1 1-hydroxy-N- (6-(2,4-d itert-a myl phen oxy)-butyl) -4-(2-ethoxycarbonylphenylazo)-2-naphthoamide in the amount of 1.7 X 10-2 mol per mol of the silver halide, and a development inhibitor releasing compound, none in the amount of 4 X 10-3 mol per mol of the same.

Third layer: A green-sensitive, low-speed silver iodobromide (containing 8 mol% silver iodide) emulsion layer (dried thickness: 3,5 ) containing a magenta coupler, 1 -(2,4,6-tri-chloro)phenyl-3- (3-(2,4- di-tert-amylphenoxy)acetamide)benzamide-5-pyrazolone in the amount of 5.8 X 10-2 mol per mol of the silver halide; a colored coupler, 1-(2,4,6-trichlorophenyl)-3-[3-(octadesenylsalicinim- ide)-2-chloro ] anilide-4-(y-naphthylazo)-5-pyrazolone in the amount of 1.7 X 10-2 mol; and a development inhibitor releasing compound, 2-(1-phenyl-5-tetrazolylthio)-4-(2,4-ditert-amylphe- noxyacetamide)-1-intanone in the amount of 7 X 10-3 mol.

Fourth layer: A A green-sensitive, high-speed silver iodobromide (containing 6 mol% silver iodide) emulsion layer (dried thickness: 2.5 ) containing the same magenta coupler, colored coupler, and development inhibitor releasing compound as in the foregoing third layer in the amounts of 1.1 x 10-2 mol, 5 X 10-3 mol, and 2 x 10-2 mol respectively per mol of the silver halide.

Fifth layer: A gelatin layer (dried thickness: 1IL) containing yellow colloidal silver and 2,5-di-tertoctylhydroquinone.

Sixth layer: A A blue-sensitive silver iodobromide (containing 7 mol% silver iodide) emulsion layer (dried thickness: 6y) containing gelatin in the amount of 350 g. per mol of the silver halide; an yellow coupler, a-pivaloyl-a-(1 -benzyl-2-phenyl-3,5-dioxo-triazolidine-4-yl)-5'-[&alpha;(2,4-di-tert-amylphe- noxy) butylamide]-2'-chloroacetanilide in the amount of 3 X10-' mol; mol; and a hardener, 1,2- bis(vinyl sulfonyl)ethane.

On the sixth layer, protective layers having the following compositions were further coated as the seventh and eighth layers. The compositions of the upper and lower protective layers are shown in Table 5: Table 5 The upper and lower protective layer compositions Sample No. e Binder (gelatin) 0.6g/m2 Matting agent Polymethyl acrylate in the average particle diameter of 2y. O.04g/m2 Colloidal silica Aerosil-200 (1) 0.12g/m2 Organic fluoro -- Upper compound (2) 6g/m2 Polyoxyethylene 1 Smg/m2 series compound (3) Polyoxyethylene 1 15mg/m2 series compound (4) Sliding agent The compound described in Example 2.

0. 2g/m2 Coating aid Sodium di-2-ethyl hexyl sulfosuccinate 0.01 g/m2 Binder 1.0g/m2 Lower Dispersant (5) 0.18g/m2 Coating aid Saponin 0.05g/m2 Note: (1) grain diameter: 12 my (2) Exemplified Compound F-(23) (3) The compound having the formula:

(4) The compound having the formula:

(5) 9g. of the compound having the formula given below was dissolved by heating to 65 C.

into a mixture of 15g. of dioctyl phthalate and 6g. of ethyl acetate, and the resulting solution was added with stirring to 100cc of 5% aqueous gelatin solution containing 1 g of sodium triisopropylnaphthalene sulfonate heated to 50at., which was then put five times repeatedly through a colloidal mill to be dispersed, whereby a dispersed liquid was prepared.

A A pair of pieces in five square centimeter size cut out from each of samples No. 11-No. 14 after drying were allowed to stand over a period of one full day in the atmosphere conditioned at 23"C. with 80%RH, and after that the respective pairs were brought face to face into contact with each other, and the thus superposed pairs were then loaded thereon respectively with weight of 8009. in the atmosphere conditioned at 40"C. with 65%RH. Subsequently the pairs were peeled apart, and the respective areas of the adhered portions were evaluated in accordance with the criteria as shown in Example 1.

Besides the above, a pair of 35mm wide by about 1 meter long strips with perforations were prepared from each of the foregoing samples, one group of which was allowed to stand over a period of three days in the atmosphere conditioned at 23 C. with 20%RH to be regarded as the group of non-aged samples, while the other group of which was allowed to stand over a period of 21 days in the air conditioned at 40 C. with 65%RH to be regarded as the group of aged samples. Both the groups of samples were measured on their torn length using the same wedge type tester as used in Example 1 as well as on the degrees of devitrification thereof in the same manner as in Example 2. The results are shown in Table 6: Table 6 Test Results Sample No. (11) (12) (13) (14) Evaluation on adhesiveness B A A B Brittleness test Non-aged (torn length in mm) 32 28 27 33 Degree of devitrification (turbidity %) 18 18 17 19 40'C/65%RH Brittleness test 21 days (torn length in mm) 45 35 37 78 In comparison of samples No. 11-No. 14 in Table 6, the methods of the present invention (samples No. 11No. 13) are found out to be improved in the brittleness in aging, above all, significantly good results are found in samples No. 12 and No. 13, which contain polyoxyethylene series compounds. In addition, little differences were found in the adhesiveness abd degree of devitrification as compared to the non-aged.

Claims (15)

1. A photographic material which comprises a support carrying at least one layer of a lightsensitive silver halide emulsion and an outermost, hydrophilic, layer comprising colloidal silica having an average grain diameter of less than 100 m# and an organic fluoro compound.

2. A photographic material according to claim 1 wherein the average grain diameter is less than 50 my.

3. A photographic material according to claim 1 or 2 wherein the outermost, hydrophilic, layer comprises gelatin.

4. A photographic material according to claim 3 wherein the ratio of the amount by dry weight of colloidal silica to the weight of gelatin in the outermost, hydrophilic, layer is 0.05:1 to 2.0:1.

5. A photographic material according to any one of the preceding claims wherein the outermost, hydrophilic, layer comprises a compound comprising repeating oxyethylene groups.

6. A photographic material which comprises a support carrying at least one light-sensitive silver halide emulsion layer and an outermost, hydrophilic, layer, said material being substantially as hereinbefore described with reference to Samples (4) or (5) of Example 1, Samples (9) or (10) of Example 2 or any one of Sample (11) to (13) of Example 3.

7. A composition for use in the preparation of a protective layer for a photographic material, which composition comprises colloidal silica having an average grain diameter of less than 100 I m# and an organic fluoro compound.

8. A composition according to claim 7 wherein the average grain diameter is less than 50 my.

9. A composition according to claim 7 or 8 further comprising a binder.

10. A composition according to claim 9 wherein the binder is gelatin.

11. A composition according to claim 10 wherein the ratio of the amount by dry weight of colloidal silica to the weight of gelatin is 0.05:1 to 2.0:1.

12. A composition according to any one of claims 7 to 11 further comprising a compound comprising repeating oxyethylene groups.

13. A composition for use in the preparation of a protective layer for a photographic material, said composition being substantially as hereinbefore described with reference to Samples (4) or (5) of Example 1, Samples (9) or (10) of Example 2 or any one of Samples 11 or (13) of Example 3.

14. A process for the preparation of a photographic material having an outermost, protective, layer, which process comprises coating the face or faces which it is desired to protect of a photographic material comprising a support carrying at least one layer of a light-sensitive silver halide emulsion with a composition as claimed in any one of claims 7 to 13.

15. A process for the preparation of a photographic material having an outermost, protective, layer, said process being substantially as hereinbefore described with reference to Samples (4) or (5) of Example 1, Samples (9) or (10) of Example 2 or any one of Samples (11) to (13) of Example 3.