Minnesota Mining and Manufacturing Company

Ronald W Burrows

Bernard A Lea

Kevin P Hall

Charles G Barlow

Ivan H Skoog

Thomas D Hellings

James B Philip, Jr

Mark P Kirk

Jonathan P Kitchin

Keith A Penfound

Duncan M Grieve

John Souter

David B Oliff

A heptamethine cyanine dye in which both nitrogen atoms of the cyanine chromophore bear a carboxyalkyl substituent comprising an alkyl chain of at least five carbon atoms. The dyes are useful as sensitisers in photothermographic imaging materials.

Photothermographic imaging materials and sensitisers therefor

Compounds suitable for use as antihalation or acutance dyes in silver halide photographic emulsions having a nucleus of the general formula (I), ##STR1## in which: Y and Z independently represent the non-metallic atoms necessary to complete a carbocyclic or heterocyclic ring or a fused ring system,

Near infrared antihalation dyes

Cyanine dyes are disclosed having a nucleus of the formula: ##STR1## wherein; A and B are independently selected from the group consisting of heterocyclic ring nuclei and heterocyclic fused ring nuclei so as to complete a cyanine dye,

Infra-red sensitive photographic materials

Infra-red sensitizing dyes for silver halide having a nucleus of the general formula: ##STR1## in which Q represents Cl or Br,

Infra-red sensitizing dyes for silver halide

Infra-red sensitizing dyes for silver halide having a mucleus of the general formula: ##STR1## in which: Q represents Cl or Br,

Infra-red sensitising dyes for silver halide

Presensitized sheets for color proofing comprising a removable carrier sheet bearing a photosensitive medium sensitive to radiation within the wavelength band 325 to 700 nm and comprising photohardenable, photoadherent, photoinsolubilisable or photosolubilisable material, the sheet including a removable antihalation layer which is removed either when stripping the carrier sheet or during subsequent processing. The antihalation dyes may be positioned within a transparent carrier sheet, in a layer on the carrier sheet opposite to the photosensitive medium or in a layer positioned between the carrier sheet and light-sensitive medium.

Pre-press light-sensitive color proofing article incorporating

High contrast negative acting silver halide emulsions suitable for laser scanning applications comprising a Group VIII metal compound and one or more spectrally sensitizing dyes of the formula ##STR1## The emulsions have good long term stability and good sensitivity.

Silver halide photographic materials

A photographic element of the conventional wet processed type or of the dry silver type which includes an antihalation or acutance dye which absorbs in the near infrared and has a relatively low visible absorption while retaining a high extinction coefficient at .sub.max. The dye is of the general formula: ##STR1## in which: m+p=2,

Photographic elements incorporating antihalation and/or acutance dyes

Images produced in photothermographic emulsions using silver halide as a light-sensitive material therein suffer from light scattering effects on the silver halide. Acutance dyes, many of which are novel, are disclosed which can absorb scattered light and which are bleached at the development temperature of the photothermographic composition.

Growing community of inventors

Harlow, United Kingdom

Ronald W Burrows