Agfa Gevaert Nv

Agfa-gevaert

Luc J Wabbes

Jos A Vaes

Eric Verschueren

Jean-Marie O Dewanckele

Guido I Hauquier

Piet Kok

Willem Cortens

According to the present invention there is provided an imaging element for making a lithographic printing plate, including on a first side of a flexible support a surface capable of being differentiated in oleophilic and oleophobic areas upon imaging and on a second side opposite to the first side a layer or a package of layers, characterized in that the layer or package of layers on the backside has a ratio of the squared value of the gravimetric water absorption (WA) in g/m,over the mean roughness in &mgr;m greater than 20.

Imaging element for making lithographic printing plates with a decreased slippage in the press

The present invention provides an imaging element comprising on a support in the order given a photosensitive layer comprising a silver halide emulsion and an image receiving layer containing physical development nuclei in water permeable relationship with said emulsion layer, characterized in that said imaging element comprises at least 50 mg/m.sup.2 of tetramethyl reductic acid and at least 100 mg/m.sup.2 of ascorbic acid. According to the present invention there is further provided a method for making a lithographic printing plate comprising the steps of image-wise exposing an imaging element as defined above and subsequently developing a thus obtained imaging element by an alkaline processing liquid in the presence of developing agent(s) and silver halide solvent(s).

Imaging element and method for making a lithographic printing plate

The present invention provides an imaging element comprising on a support in the order given (i) a base layer comprising a binder in an amount between 1 and 3 g/m.sup.2, (it) a photosensitive layer comprising a spectrally sensitised silver halide emulsion, said emulsion consisting principally of silver chloride but containing bromide ranging from 0.1 mole % to 40 mole % and iodide ranging from 0 to 2 mole % and (iii) a receiving layer containing physical development nuclei in water permeable relationship with said photosensitive layer, characterized in that the ratio by weight of gelatin to silver halide (expressed as an equivalent amount of AgNO.sub.3) in said photosensitive layer is at least 1.35.

The present invention provides a method for making a lithographic printing plate according to the silver salt diffusion transfer process comprising the steps of:

Method for making a lithographic printing plate using ascorbic acid

The present invention provides a method for obtaining a photographic material by coating on a support at least one layer comprising at least one photosensitive silver halide emulsion wherein the silver halide crystals contain silver chloride for at least 60 mole %, silver bromide in a range from 5 mole % to 40 mole % and silver iodide in a range from 0 mole % to 1 mole %, characterized in that a water soluble iridium compound is added between the end of the physical ripening and the end of the chemical ripening to said silver halide emulsion at a pH between 4 and 6.5, at a pCl between -0.3 and 1 and at a ratio by weight of gelatin to silver halide, expressed as equivalent amount of silver nitrate between 0.05 and 0.5.

Method for obtaining a photographic material suitable for use in

Method for making a lithographic printing plate

The present invention provides a photographic material comprising a silver halide emulsion layer sensitized to light above 700 nm by means of an infrared sensitizing dye having a maximum absorption between 700 nm and 850 nm characterized in that said silver halide emulsion further comprises a red sensitizing dye of the cationic type having a maximum absorption between 600 nm and 700 nm. The thus obtained photographic material shows an increased sensitivity in the infrared region. The material can be used in as silver salt diffusion transfer process to prepare a lithographic printing plate.

Infrared sensitive silver halide photographic material

A new class of photographic stabilizers is prepared and their use in photographic materials is disclosed. These compounds are 1-phenyl-3-pyrazolidinone derivatives corresponding to following general formula: ##STR1## wherein: A represents a group capable of adsorbing at the surface of silver halides;

Photographic stabilizers with 1-phenyl-3-pyrazolidinone moieties

The present invention provides a method of preparing a planographic printing plate comprising the steps of:

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Mortsel, Belgium

Luc J Wabbes