Abstract:
A method for producing a predetermined resist pattern on for example a lithographic printing plate, circuit board or mask, comprises the imagewise exposure of a radiation sensitive positive working coating using a suitable radiation such as direct heat radiation, UV radiation, visible radiation, infrared radiation or electron beam radiation. The method is characterised by the use of a novel polymeric material which is functionalised by groups Q to render it insoluble in a developer, but such that exposure to the radiation renders it soluble therein. The groups Q are not diazide groups as is conventional, but are groups which do not release nitrogen on exposure to the radiation, and have hydrogen bonding capability. Examples of groups Q are 2-naphthylsulphonyloxy, 2-thienylsulphonyloxy, dansyloxy, p-toluenesulphonyloxy, benzoyloxy and n-butylsulphonyloxy.
Abstract:
There is described a method of forming a lithographic plate by the heat-mode imaging method which comprises coating on a base which can be used as a lithographic base, a positive working photosensitive composition which comprises a naphthoquinone diazide ester of a phenolic resin or a naphthoquinone diazide ester and a phenolic resin and at least one substance which absorbs infrared radiation, overall exposing the assembly to ultraviolet light to render the photosensitive composition developable, imaging the plate by means of a laser which emits in the infrared region of the spectrum and then developing the plate to remove those areas of the photosensitive composition not exposed to the laser.
Abstract:
Single- and multi-layer positive-working imageable elements include an ink receptive outer layer includes a primary polymeric binder that is a poly(vinyl phenol) or a phenolic polymer having certain acidic groups. The use of this type of polymeric binder makes the imaged elements developable in low pH (11 or less) alkaline developers.
Abstract:
A method for producing a predetermined resist pattern on for example a lithographic printing plate, circuit board or mask, comprises the imagewise exposure of a radiation sensitive positive working coating using a suitable radiation such as direct heat radiation, UV radiation, visible radiation, infrared radiation or electron beam radiation. The method is characterised by the use of a novel polymeric material which is functionalised by groups Q to render it insoluble in a developer, but such that exposure to the radiation renders it soluble therein. The groups Q are not diazide groups as is conventional, but are groups which do not release nitrogen on exposure to the radiation, and have hydrogen bonding capability. Examples of groups Q are 2-naphthylsulphonyloxy, 2-thienylsulphonyloxy, dansyloxy, p-toluenesulphonyloxy, benzoyloxy and n-butylsulphonyloxy.
Abstract:
A method for producing a predetermined resist pattern on e.g. a lithographic printing plate, circuit board or mask comprises the imagewise exposure of a radiation sensitive diazide-containing coating (conventionally considered as a UV sensitive material), to non-UV radiation, such as direct heat radiation or infra-red radiation. A positive of the exposed image is revealed on development. Additionally, it has been found that a flood exposure to UV radiation after the imagewise exposure to the non-UV radiation means that a negative of the exposed image is revealed, on development.
Abstract:
There is described coated on a lithographic base a complex of a developer-insoluble phenolic resin and a compound which forms a thermally frangible complex with the phenolic resin. This complex is less soluble in the developer solution than the uncomplexed phenolic resin. However when this complex is imagewise heated the complex breaks down so allowing the non-complexed phenolic resin to the dissolved in the developing solution. Thus the solubility differential between the heated areas of the phenolic resin and the unheated areas is increased when the phenolic resin is complexed. Preferably a laser-radiation absorbing material is also present on the lithographic base. A large number of compounds which form a thermally frangible complex with the phenolic resin have been located. Examples of such compounds are quinolinium compounds, benzothiazolium compounds, pyridinium compounds and imidazoline compounds.
Abstract:
There is described a lithographic plate which comprises a base coated with a photopolymerisable composition which comprises a polymeric binder, at least one free-radically polymerisable ethylenically unsaturated compound and as the photoinitiator combination a metallocene compound, N-phenyl glycine or a substituted N-phenyl glycine or an N-phenyl glycine derivative together with a third component which is a substance which helps in the reaction initiation but also increases the sensitivity of the photopolymerisable composition to a desired region of the spectrum.