Abstract: A method of making a relief image printing element from a photosensitive printing blank is provided. A photosensitive printing blank with a laser ablatable layer disposed on at least one photocurable layer is ablated with a laser to create an in situ mask. The printing blank is then exposed to at least one source of actinic radiation through the in situ mask to selectively cross link and cure portions of the photocurable layer. Diffusion of air into the at least one photocurable layer is limited during the exposing step and preferably at least one of the type, power and incident angle of illumination of the at least one source of actinic radiation is altered during the exposure step. The resulting relief image comprises a plurality of dots and a dot shape of the plurality of dots that provide optimal print performance on various substrates, including corrugated board.

Abstract: A method of creating a digital mask in situ for use in a process of making digital flexographic printing elements. The digital mask is created by laminating the negative image that is the by-product of a thermal proofer to a photosensitive printing plate. Thereafter, the photosensitive printing element can be imaged, exposed, and developed in the usual manner.

Abstract: A method of creating a digital mask in situ for use in a process of making digital flexographic printing elements. The digital mask is created by laminating the negative image that is the by-product of a thermal proofer to a photosensitive printing plate. Thereafter, the photosensitive printing element can be imaged, exposed, and developed in the usual manner.

Abstract: A method of creating a digital mask in situ for use in a process of making digital flexographic printing elements. The digital mask is created by laminating the negative image that is the by-product of a thermal proofer to a photosensitive printing plate. Thereafter, the photosensitive printing element can be imaged, exposed, and developed in the usual manner.

Abstract: The present invention is directed to the manufacture of “seamless” photosensitive printing elements from substantially planar printing plate blanks wrapped around cylindrical printing sleeves or carriers. The method comprises the steps of cutting a photosensitive printing element to a size for wrapping around a printing sleeve, trimming ends of the photosensitive printing element to create a gap when the printing element is wrapped around the printing sleeve, attaching the photosensitive printing element to the printing sleeve and filling the gap between the ends of the photosensitive printing element with a filler material.

Abstract: A method of creating a digital mask in situ for use in a process of making digital flexographic printing elements. The digital mask is created by laminating the negative image that is the by-product of a thermal proofer to a photosensitive printing plate. Thereafter, the photosensitive printing element can be imaged, exposed, and developed in the usual manner.

Abstract: An edge-covering composition for covering the cut surfaces of a photosensitive printing element to prevent premature curing of the cut surfaces during a process of manufacturing the printing element. The edge-covering composition is an emulsion comprising one or more emulsifiers, one or more-ultraviolet radiation-absorbing materials, optionally, a coloring agent, and optionally, one or more additional additives. The emulsion compositions are easy to apply, non-toxic, inexpensive, and are largely compatible with the solvents used to wash uncured photopolymer from the printing elements during processing.

Abstract: An automated method of preventing edge curing of cut surfaces of photosensitive printing elements is disclosed. Once a photosensitive printing element is cut in a pattern of a desired size and shape, a portion of the coversheet on a periphery of the cut edges of the printing plate is removed, while leaving intact the layer of photocurable material and the optional ablation layer beneath the coversheet. Next, an edge cure prevention composition is applied to the optional ablation layer or the layer of photocurable material revealed by the removal of the portion of the coversheet. Once the edge cure prevention composition is dried, the remainder of the coversheet may be removed from the photosensitive printing element and the printing element may be mounted on a sleeve or cylindrical carrier for further processing. The method ensures that the edge cure prevention composition is applied only to areas where it is needed and does not affect imageable areas of the printing plate.

Abstract: An inkjet printer is used to apply an ink that is substantially opaque to actinic radiation in at least one wavelength region effective to cure the photosensitive printing plate to the edges and corners, of a printing plate after the plate has been trimmed (i.e., cut) to a suitable size and shape for mounting on a printing sleeve or cylinder. Use of inkjet printing allows for the cut surfaces of the plate to quickly and accurately be coated with a UV-opaque ink and prevents, or substantially eliminates, undesirable curing of cut surfaces of a photosensitive printing plate. The ink covers the photocurable surfaces exposed by the cutting process and prevents the cut surfaces of the printing plate from undesirably curing until proper exposure and development of the printing plate.

Abstract: An automated method of preventing edge curing of cut surfaces of photosensitive printing elements is disclosed. Once a photosensitive printing element is cut in a pattern of a desired size and shape, a portion of the coversheet on a periphery of the cut edges of the printing plate is removed, while leaving intact the layer of photocurable material and the optional ablation layer beneath the coversheet. Next, an edge cure prevention composition is applied to the optional ablation layer or the layer of photocurable material revealed by the removal of the portion of the coversheet. Once the edge cure prevention composition is dried, the remainder of the coversheet may be removed from the photosensitive printing element and the printing element may be mounted on a sleeve or cylindrical carrier for further processing. The method ensures that the edge cure prevention composition is applied only to areas where it is needed and does not affect imageable areas of the printing plate.

Abstract: An edge-covering composition for covering the cut surfaces of a photosensitive printing element to prevent premature curing of the cut surfaces during a process of manufacturing the printing element. The edge-covering composition is an emulsion comprising one or more emulsifiers, one or more-ultraviolet radiation-absorbing materials, optionally, a coloring agent, and optionally, one or more additional additives. The emulsion compositions are easy to apply, non-toxic, inexpensive, and are largely compatible with the solvents used to wash uncured photopolymer from the printing elements during processing.

Abstract: An inkjet printer is used to apply an ink that is substantially opaque to actinic radiation in at least one wavelength region effective to cure the photosensitive printing plate to the edges and corners, of a printing plate after the plate has been trimmed (i.e., cut) to a suitable size and shape for mounting on a printing sleeve or cylinder. Use of inkjet printing allows for the cut surfaces of the plate to quickly and accurately be coated with a UV-opaque ink and prevents, or substantially eliminates, undesirable curing of cut surfaces of a photosensitive printing plate. The ink covers the photocurable surfaces exposed by the cutting process and prevents the cut surfaces of the printing plate from undesirably curing until proper exposure and development of the printing plate.

Abstract: High-quality composite printing elements are prepared without the need for precise registration of constituent photocurable elements by disposing at least one photocurable element, and preferably a plurality of photocurable elements, upon a surface of a printing element in approximate register and then transferring a computer-generated negative onto a surface of the elements.

Abstract: High-quality composite printing elements are prepared without the need for precise registration of constituent photocurable elements by disposing at least one photocurable element, and preferably a plurality of photocurable elements, upon a surface of a substantially planar carrier sheet in approximate register and then transferring a computer-generated negative onto a surface of the elements.

Abstract: High-quality composite printing elements are prepared without the need for precise registration of constituent photocurable elements by disposing at least one photocurable element, and preferably a plurality of photocurable elements, upon a surface of a printing element in approximate register and then transferring a computer-generated negative onto a surface of the elements.

Abstract: High-quality composite printing elements are prepared without the need for precise registration of constituent photocurable elements by disposing at least one photocurable element, and preferably a plurality of photocurable elements, upon a surface of a substantially planar carrier sheet in approximate register and then transferring a computer-generated negative onto a surface of the elements.

Abstract: High-quality composite printing elements are prepared without the need for precise registration of constituent photocurable elements by disposing at least one photocurable element, and preferably a plurality of photocurable elements, upon a surface of a printing element in approximate register and then transferring a computer-generated negative onto a surface of the elements.