Ilford Limited

John L Cawse

Peter J Elton

George Littler

Peter J Herring

Philip J Harris

John C Clarke

Andrew Wigglesworth

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.

Antistatic backing for photographic roll film

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. Most preferably one polymer has a refractive index which is as much below 1.54 as the other polymer has a refractive index above 1.54. Preferably the final particles comprises substantially equal amounts of the two polymers.

Preparation of polymer dispersions and photographic elements containing

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.

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Macclesfield, United Kingdom

John L Cawse