Thermal processor and method for using the same

A method of thermally developing a photopolymer relief image printing element, wherein the photosensitive printing element comprises a flexible substrate and at least one layer of photosensitive material comprising cured portions of photosensitive material and uncured portions of photosensitive material on the flexible substrate, the method comprising the steps of:

• a. securing a photosensitive printing element to a conveying means, wherein the conveying means comprises a conveyor supported by at least a first roller and a second roller, wherein the first roller is adjacent to a position at which the photosensitive printing element is brought into contact with a web of absorbent material and the second roller is positioned at a distance from the first roller;
• b. heating the photosensitive printing element from a first temperature to an operating temperature of a heatable roller in an auxiliary heating zone, where the auxiliary heating zone is configured to heat the photosensitive printing element from a first temperature to the operating temperature of the heatable roller, and wherein the operating temperature of the heatable roller is a temperature sufficient to cause at least a portion of the photosensitive printing element to soften or liquefy when an absorbent material is brought into contact with the at least one layer of photosensitive material;
• c. applying heat to the photosensitive printing element on the conveyor from an external heater positioned adjacent to a point where the absorbent material contacts the photosensitive printing element on the conveyor;
• d. supplying an absorbent material to at least a portion of an outer surface of the heatable roller, said heatable roller being mounted for rotation in the frame, wherein the absorbent material is capable of absorbing material that is liquefied or softened from the photosensitive printing element when the heatable roller is heated and the absorbent material contacts at least a portion of the photosensitive printing element;
• and
• e. causing the photosensitive material and the absorbent printing element to come into contact at a point between the conveyor and the heatable roller such that at least a portion of the liquefied or softened material is absorbed by the absorbent material.

A thermal development apparatus for forming a relief structure on a photosensitive printing element, wherein the photosensitive printing element comprises a flexible substrate and at least one layer of photosensitive material comprising cured portions of photosensitive material and uncured portions of photosensitive material on the flexible substrate, the apparatus comprising:

• a. an enclosure;
• b. conveying means upon which the photosensitive printing element is securable, wherein the conveying means comprises a conveyor supported by at least a first roller and a second roller, wherein the first roller is arranged adjacent to a position at which the photosensitive printing element is brought into contact with a web of absorbent material and the second roller is positioned at a distance from the first roller;
• c. a heatable roller mounted in the enclosure, wherein the heatable roller is heated to and maintained at an operating temperature at which the uncured portions of photosensitive material begins to liquefy or soften;
• d. an absorbent material covering at least a portion of the heatable roller, wherein the absorbent material is capable of absorbing liquefied or softened uncured portions of photosensitive material from the photosensitive printing element when the photosensitive printing element comes into contact with the absorbent material on the portion of the heatable roller;
• e. an auxiliary heating zone arranged relative to the conveying means, wherein the auxiliary heating zone is configured to heat the photosensitive printing element from a first temperature at a location at which the photosensitive printing element enters or re-enters the thermal development apparatus to the operating temperature of the heatable roller;
• and
• f. a cooling system positioned below the continuous loop of the conveying means, wherein the cooling system controls a temperature of the flexible substrate.