Abstract: There is described a method of processing silver halide photographic material in a processing machine using a developing solution which comprises either a hydroquinone type developing agent or a reductone type developing agent, together with an electron transfer agent as an auxiliary developing agent, and with at least one basic compound the anion of which is carbonate, sulphite or hydroxide, where in the presence of a compound of formula (I), Ar is an aromatic ring or heterocyclic aromatic ring which is optionally substituted.

Abstract: There is described a photographic developing solution which comprises as an image toning agent a compound of formula I: ##STR1## where Ar is an aromatic or heteroaromatic ring which may be substituted, in a concentration of at least 0.00035 moles/liter.

Abstract: There is described a concentrated photographic silver halide developing solution which comprises from 50 to 150 g/liter of an ascorbic acid type compound of the general formula I: ##STR1## or alkali metal salts thereof, in which the group R represents a hydroxylated alkyl group, and at least one basic compound the anion of which is carbonate, sulphite or hydroxide of which the cation is an alkali metal, especially sodium or potassium, the total sodium to total potassium ion ratio in the concentrated developing solution being from about 50:50 to 0:100 (mole: mole).Preferably the concentrated solution is entirely aqueous but it may comprise a proportion of water-miscible organic solvents such as ethyl alcohol, or glycol solvents.

Abstract: There is provided a roll film assembly which comprises a length of photographic film having attached to each end thereof a length of backing paper, the film and the backing paper being wound together on a flanged spool, the backing paper being a laminate of paper and polyethylene which comprises as an opaqueing agent a layer of polyethylene which comprises from 7 to 10% by weight of carbon black particles of which from 20 to 100% by weight are conductive carbon particles.

Abstract: There is described a fixing bath for developed silver halide photographic material which comprises as the active silver halide solvent a combination of sodium thiosulphate and potassium thiosulphate, the molar ratio of sodium to potassium being from about 2:3 to about 3:2.

Abstract: A photographic material processor which having at least two processing tanks for solutions used in the processing of photographic material, and one positive displacement pump for each processing solution for transferring concentrated processing solution and water to said processing tanks, the processor also comprising means for connecting each pump to a concentrated solution container and to a water source by a two-way valve, means for measuring the area of photographic material processed and means for activating the said pumps when a predetermined area of photographic material has been processed to perform a replenishment cycle, means for directing the liquid flow in each two-way valve so that during each replenishment cycle a predetermined volume of concentrate processing solution and a predetermined volume of water are pumped to the processing tanks by each PUMP.

Abstract: There is described a concentrated developer solution which comprises from about 20 to about 60 g/l of dihydroxybenzene developing agent, preferably hydroquinone, from about 0.5 to about 3.0 g/l of an auxiliary developing agent, preferably 1-phenyl-3 pyrazolidinone, from about 300 to about 500 g/l of potassium sulphite and which is buffered to a pH of from about 8 to about 10 with a buffering agent other than an alkanolamine and which comprises sufficient organic solvent other than an alkanolamine to dissolve the hydroquinone.Such a concentrated developing solution which contains a high concentration of potassium sulphite has when diluted a long useful life and produces images of low graininess.

Abstract: There is described a process for the spectral sensitization of photographic silver halide emulsions which comprises forming and chemically sensitizing silver halide crystals in a colloid dispersion medium, the process being characterized in that it comprises forming a shell of silver halide on the chemically sensitized crystals by simultaneously adding to the dispersion an aqueous solution of a water soluble halide or pseudo-halide, an aqueous solution of silver nitrate and a J-band aggregating spectral sensitizing dye in an aqueous medium, the said simultaneous additions being continued for sufficient time to form a shell of silver halide or pseudo-halide on the said chemically sensitized silver halide crystals which is up to 15 mole percent of the total silver halide or pseudo-halide of the fully grown crystals.

Abstract: An article has a light-transparent visual display feature through which a graphic design or a solid object can be seen, the light-transparent visual display feature is a light-transparent film sheet which contains a Lippman-Bragg reflection hologram which has a viewing angle of not more than 20.degree. on either side of a selected viewing axis or axes and a depth of holographic image which is not more than 5 mm on one side or the other of the image plane. When the article is a package, the restricted view is provided around a vertical axis relative to the observer so that as an observer passes the illuminated package laterally witth the hologram on the vertical face, the hologram will suddenly come into view and just as suddenly slip from view as viewing angle is passed. When the article is an identification or credit card, the transparent film material bearing the hologram is laminated to the top surface of the card which bears a graphic design relevant to the holder of the card.

Abstract: It is the object of this invention to provide a method for the preparation of an antiblocking agent which is effective in its antiblocking activity but is considerable less visible in photographic enlargements made from the film containing the antiblock of this invention.There is described a process for the preparation of monodispersed polymer particles between 5 and 10 microns in diameter which comprises preparing a dispersion of monosized seed polymer particles and then adding to this dispersion an ethylenically unsaturated monomer which is different from the monomer used to prepare the seed polymer particles, together with a polymerization initiator and completing the polymerization, the refractive index of one of the polymers produced being greater than 1.54 and the refractive index of the other polymer being less than 1.54.The refractive index of gelatin is 1.54. There is produced by the process of the present invention a particle which comprises two polymers.

Abstract: Azo dyes of the formula ##STR1## where X is alkyl or alkoxy each of 1 to 4 carbon atoms or halogen, X' is hydrogen, alkyl or alkoxy each of 1 to 4 carbon atoms or halogen, Y and Y' are independently of each other hydrogen or halogen, Z is hydrogen, alkyl or alkoxy or alkylthio each of 1 to 4 carbon atoms, or halogen, M is a 1-, 2- or 3-valent metal cation, ammonium or an organic ammonium compound, m is 1, 2 or 3 and n is 2 to 10, are suitable for use as image dyes in photographic silver dye bleach materials.The dyes of the invention can also be used to dye textile materials.

Abstract: There is described a method of preparing a silver halide emulsion wherein the silver halide crystals are of the twinned type which comprises the steps of (a) forming or providing in a colloid dispersing medium silver halide crystals containing at least 90 mole % iodide, at least 90% of which are of the hexagonal lattice structure with a mean thickness of less than 0.

Abstract: A method of preparing a latex of a color coupler polymer which method in characterized in that it comprises dissolving in at least one ethylenically unsaturated non-coupling monomer which is liquid at room temperature at least two monomeric color couplers, the total amount of couplers being from 1 to 50% by weight of the non-coupling monomer, and dispersing this solution in an aqueous solution of a surfactant and a polmerization initiating system, and wherein the melting point of the mixture of monomeric color couplers is below the reaction temperature of said polmerization system.

Abstract: There is described a method of preparing a silver halide emulsion wherein the silver halide crystals are of the twinned type which comprises the steps of (a) providing in a colloid dispersion medium silver halide crystals containing at least 90% iodide and at least 80% of which are hexagonal lattice structure with each displaying predominantly a single basal face, (b) mixing in the dispersing medium containing the sail silver iodide crystals an aqueous solution of an alkali metal of ammonium bromide or chloride (or mixture thereof) so forming twinned silver halide crystals containing iodide and/or the halide or halides being added, optionally (c) adding a silver halide solvent to the dispersing medium and so causing the growth of the twinned silver halide crystals, and optionally (d) then causing the twinned crystals to increase in size by adding to the colloid dispersing medium further aqueous silver salt solution and further alkali metal or ammonium halide and then finally optionally (e) removing the water-

Abstract: A method of preparing a copy hologram from a master hologram in which the light employed in the copying process is modified by passing an exposing beam through a light modulating array. At least some members of the array have modified light transmissivities in accordance with information derived from a reconstruction of the master hologram.

Abstract: Compounds of the formula ##STR1## where A represents the atoms necessary to complete a benzoxazole or naphthoxazole ring which is optionally substituted, R.sub.1 and R.sub.2 are each alkyl, hydroxyalkyl or alkoxy alkyl groups wherein the alkyl moiety comprises 1 to 4 carbon atoms, R.sub.3, R.sub.4, R.sub.5 and R.sub.6 are each hydrogen atoms or alkyl groups having 1 to 4 carbon atoms or phenyl groups, and X is an anion.

Abstract: There is described a method of processing exposed holographic material to obtain holograms having a broader band replay a hologram which is of the silver halide in gelatin binder type which method comprises holographically exposing the holographic material by use of coherent light, developing the holographic image by a chemical process and then treating the material sequentially either firstly with a solution of an anionic surfactant which comprises at least one alkyl group having at least four carbon atoms and then with a solution of a quaternary ammonium compound which comprises at least one alkyl group having from 10 to 18 carbon atoms or a polymeric compound which comprises at least one quaternary ammonium group in the repeating unit or firstly with a solution of said quaternary ammonium compound or polymeric compound and then with a solution of an anionic surfactant, the material being subjected to a silver bleaching step at one stage after development.

Abstract: A method of preparing a color separation holographic master which can be used in the preparation of a colored hologram of an object, by illuminating the object with light having a very narrow wavelength range and capturing the reflectance values on the object using a detector placed as if it were along the axis of the laser to be used for the holographic exposure and storing these reflectance values as a positive image, then carrying out a holographic exposure of the object using a laser there being present in the object beam between the laser and the object as a light modulating means the positive image of the captured reflectance values, and then processing the holographic material to fix the holographic fringes therein.

Abstract: A method of preparing a hologram of an object on holographic material by a holographic laser exposure, by illuminating the object with white light and capturing the luminance values of the object using a detector having a filter which simulates the response of the human eye to luminance values and which detector is placed as if it were along the axis of the laser to be used for the holographic exposure and storing the luminance information as a positive image, illuminating the object with incident light of substantially the same wavelength as the laser light to be used for the holographic exposure and capturing the reflectance values from the object using a detector which is placed as if it were along the axis of the laser to be used for the holographic exposure and storing the reflectance information as a negative image, carrying out a holographic exposure of the object on to holographic material there being present in the object beam between the laser and the object light modulation means which represents t

Abstract: There is described a method of preparing a hologram laminated between two sheets of glass which comprises forming an assembly which comprises a sheet of glass, a sheet of polyvinyl butyral, a film which contains a silver halide hologram, a sheet of polyvinyl butyral and a sheet of glass and then subjecting the assembly of a pressure of between 12 and 15 bars at a temperature about 110.degree. C. which is the softening temperature of polyvinyl butyral.