Agfa-gevaert Ag

Hans Glockner

Karl Kuffner

Ernst Meier

Immo Boie

Karl-Wilhelm Schranz

Fritz Nittel

Jozef Frans Willems

Robrecht Julius Thiers

Hugo Zorn

Improved 5-pyrazolone couplers of the following formula ##SPC1## wherein R,R.sub.1 R.sub.2,X and A denotes as described hereinafter for use in lightsensitive color photographic materials which are easy to prepare and give rise after chromogenic development to magenta dyes with improved stability to light.

Color photographic materials containing diffusion fast pyrazolone

Preparation of 1-aryl-3-anilino-pyrazolones-(5) by reacting a hydrazine with an ester from the group of dialkoxyacrylic acid ester, trialkoxy propionic acid ester or iminoalkoxy propionic acid ester to produce a .beta.-hydrazine-.beta.-alkoxyacrylic acid ester and then condensing this intermediate product with an aniline to result in the desired anilinopyrazolone. These reactions are carried out in a methanolic solution in the presence of an acetic acid catalyst.

Process for the preparation of 3-anilino-pyrazolones-(5)

Heterocyclic mercapto compounds are added to a binder layer containing colloidal silver which is comprised in a color photographic multilayer material. The colloidal silver layer may be a yellow filter layer to prevent exposure of the green, and red recording layers to blue light, or an antihalation layer arranged between the layer support and the lowermost light sensitive silver halide emulsion layer. The heterocyclic mercapto compounds reduce the contact fog produced in the (first) developer and increase color density in reversal processing. Additionally there can be present in the colloidal silver layer a sensitizer for the blue, green or red spectral region.

Color photographic multilayer material with improved color density

Anilinopyrazolone are to be prepared in high yields and with a high degree of purity by reacting a salt particularly hydrochloride of a .beta.-arylamino-.beta.-imino-propionic acid ester of one of the tautomeric formulae which are defined hereinafter with a suitable substituted hydrazine.

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Munich, Germany

Hans Glockner