Polychrome Corporation

Simon L Chu

Eugene Golda

Alan Leonard Wilkes

Robert Sharowsky

Peter Shu

Ken-ichi Shimazu

Jen-chi Huang

Jen-Chi Huang

A method for the production of aluminum substrates useful in the production of lithographic printing plates which comprises first mechanically graining at least one surface of an aluminum sheet to obtain a pumice grained surface of the aluminum sheet, and then electrolytically etching said grained surface with alternating current.

Aluminum substrates useful for lithographic printing plates

There are disclosed herein lithographic plates having an aluminum base the surface of which has been made porous and hardened first by an alternating current anodization in a hydrochloric acid electrolyte and then by a direct current anodization in a sulfuric acid electrolyte.

Electrochemically treated photo-lithographic plates

A method for producing an improved aluminum substrate for lithographic printing plates which comprises applying an interlayer bonding solution to the surface of an aluminum web, heating said interlayer solution on the surface of the said aluminum at an elevated temperature and removing any excess solution which has not reacted with the aluminum substrate.

Method for producing lithographic printing plates

A method for producing a water developable lithographic printing plate which comprises treating at least one surface of a metal sheet substrate with a layer of a lithographically suitable, light sensitive, water soluble substance and subsequently coating the thus treated base sheet with an upper layer of a water insoluble, ink receptive, lithographically suitable photosensitive composition. Said photosensitive layers must be either both positive working or both negative working. Upon imagewise exposure through a mask by standard methods the exposed areas of said upper photosensitive composition are alternatively characterized as either water permeable or water impermeable and the unexposed areas are alternatively water impermeable or water permeable as opposed to the exposed areas. Upon said imagewise exposure, the exposed lower level areas in a negative system are rendered water insoluble whereas the exposed lower level areas in a positive system are rendered more water soluble than the unexposed areas.

Water developable lithographic printing plate having dual photosensitive

Compositions comprising (I) solvent-soluble, negative-acting, light-sensitive reaction products of (a) water-soluble diazo condensation products with (b) water-insolubilizing inorganic compounds therefor and (II) synthetic, film-forming oleophilic resins, which compositions can be coated onto suitable base sheet materials to form presensitized lithographic printing plates, proofs for multi-color printing, visual aids, printed circuits and the like.

Photosensitive diazo condensate compositions

A method for preparing aluminum based lithographic printing plates which comprises treating at least one surface of an aluminum base sheet with an interlayer composition, thereafter anodizing the thus treated aluminun surface, optionally retreating the coated, anodized aluminum plate with another stratum of the interlayer composition and then applying to said surface a suitable light sensitive composition to yield the desired photosensitive lithographic printing plate of improved characteristics.

Lithographic printing plate and method of making same

A method for electrolytically graining the surface of aluminum sheets useful in the production of lithographic printing plates which comprises subjecting said aluminum sheets to the action of alternating electric current in an aqueous electrolytic solution containing, in combination, small but effective amounts of both hydrochloric and nitric acids.

Process for electrolytic graining of aluminum sheet

A moving essentially non-porous web is positioned above and in close proximity to the upper surface of a narrow, very shallow pool of coating solution. A coating meniscus extends directly from the upper surface to the web to transfer coating solution from the pool to the web. Stagnation of solution in the pool is eliminated by feeding solution to the pool at the center and bottom thereof, and removing excess solution through ports at the top surface of the pool at each end thereof.

Apparatus for meniscus coating of a moving web

In the production of lithographic printing plates, the method of anodizing the surface of an aluminum web substrate which comprises subjecting said web to an anodization treatment in an electrolyte comprised of a combination of sulfuric acid and phosphoric acid, and thereafter applying a lithographically acceptable photosensitive coating to the web to obtain a presensitized lithographic printing plate.

Method of producing lithographic printing plates

Apparatus for applying a coating of photographically sensitive liquid on one side of a moving aluminum web is constructed with a backing or support roller having stepped portions at each end of an unstepped central portion. The latter is engaged with the anterior surface of the web and is narrower than the web so that coating liquid applied to one surface of the web does not migrate to the edges of the web to contaminate the anterior side thereof. The width of the central portion is great enough so that mechanical stress on the web is not excessive and the undercut height is sufficient to exceed deflection of the web at the edges thereof.

Growing community of inventors

Dobbs Ferry, NY, United States of America

Simon L Chu