Abstract:
According to the present invention, a method is provided for preparing physical development nuclei for use in silver salt diffusion transfer processing, said physical development nuclei comprising a heavy metal sulphide, said method comprising the steps of: precipitating said heavy metal sulphide by bringing a water soluble heavy metal compound in reactive association with a water soluble sulphide in an aqueous liquid and said precipitation being carried out in the presence of a hydrophilic polymer so as to disperse said heavy metal sulphide, said hydrophilic polymer comprising a heterocyclic group, characterized in that said heterocyclic group is present in a recurring unit of said hydrophilic polymer, said recurring unit being comprised in said polymer in an amount between 0.1 mol % and 5 mol %.
Abstract:
The present invention provides a method for making a lithographic printing plate according to the silver salt diffusion transfer process using a photographic material comprising on a support a silver halide emulsion layer and a layer containing physical development nuclei comprising the steps of:image-wise exposing said photographic material;developing a thus obtained image-wise exposed photographic material by guiding said image-wise exposed photographic material through an alkaline processing liquid comprising a hydrophobizing agent, in 15s or less andsubsequently guiding a thus obtained developed photographic material through a stabilizing liquid;characterized in that said stabilizing liquid comprises a compound having a mercapto-group having a pK.sub.a of 4.5 or less.
Abstract:
A toner particles supplying device includes a pneumatic conveyor and a rotatable container or a container with a rotatable inner structure including machinery for tumbling the toner particles. The machinery for tumbling the toner particles is located on or near an inner surface of the container and serves for fluidising toner particles and urging them toward the pneumatic conveyor.
Abstract:
A toner composition is provided wherein by adding aliphatic lower molecular weight compounds which are partly or completely compatible with the binder resin(s), the melt viscosity of the toner composition can be lowered while the glass transition temperature (Tg) is more or less constant. Inclusion of these adding aliphatic lower molecular weight compounds, having a number average molecular weight, as measured by GPC in toluene, of from 500 to 3,000, results in toner compositions with a better adhesion and gloss and still an acceptable level of FOT and hot-offset. Also provide is a method for fixing toner images on a substrate.
Abstract:
A lithographic printing plate that works according to the silver salt diffusion transfer reversal process is disclosed. The lithographic properties of said plate can be improved by incorporating a hydrophilic amphoteric block copolymer, comprising a non-ionic block of acrylic units with pendant nitrile groups and an acrylamid(in)e block which comprises units with pendant basic and acidic groups. The hydrophilic amphoteric block copolymer is preferentially present in the image receiving layer of the lithographic printing plate. In an alternative embodiment, said block copolymer may be present in a treating solution used for processing said plate or applied onto said plate while printing. The hydrophilicity of the printing plate's surface is improved without deteriorating the ink-acceptance in the printing areas.
Abstract:
The present invention provides a method for making a lithographic printing plate according to the silver salt diffusion transfer process comprising the steps of: image-wise exposing an imaging element comprising on a support a photosensitive layer comprising a silver halide emulsion and an image receiving layer containing physical development nuclei, developing said imaging element in the presence of at least one developing agent and at least one silver halide solvent using an alkaline processing liquid and neutralizing a thus obtained developed imaging element using a neutralization solution having a pH between 4 and 10.5 and comprising a buffer characterized in that said neutralization solution comprises 2-methyl-3(2H)-isothiazolone.
Abstract:
The present invention provides a method for making a lithographic printing plate according to the silver salt diffusion transfer process comprising the following steps: image-wise exposing with a high intensity-short time exposure an imaging element comprising on a support a photosensitive layer comprising at least one photosensitive silver halide emulsion comprising a heterocyclic compound containing at least one nitrogen atom in the ring and an image receiving layer comprising physical development nuclei in water permeable relationship with said photosensitive layer, developing said imaging element using an alkaline processing liquid in the presence of (a) developing agent(s) and (a) silver halide solvent(s), characterized in that said heterocyclic compound containing at least one nitrogen atom in the ring comprises at least one mercapto- or thione group and one substituent comprising at least 5 carbon atoms selected from the group consisting of linear or branched alkyls, alkenyls, alkynyls, aralkyls and alkylaryls.
Abstract:
A kit for preparing a processing liquid for use in preparing a lithographic printing plate according to silver salt diffusion transfer processing, and comprising all necessary active compounds for preparing said processing liquid, said active compounds including a solid hydrogensulphite amine complex or a solid sulphurdioxide amine complex, said amine of said complexes being capable of acting as a silver halide solvent.
Abstract:
The present invention provides an imaging element comprising on the same side of a support in the order given a base layer, a light sensitive layer containing a silver halide emulsion and a surface layer comprising physical development nuclei characterized in that said base layer and/or said light-sensitive layer comprises gelatin being hardened with a divinylsulfonyl hardener such that the time needed to completely brake down said base layer, light sensitive layer and surface layer using an aqueous solution of 0.14% by weight of NaOCl at 25.degree. C. is between 1000s and 1600s. A lithographic printing plate can be obtained with such imaging element according to the silver salt diffusion transfer process and exhibits an improved printing endurance.