Abstract:
Thermally developing a photocurable printing blank to produce a relief pattern comprising a plurality of relief dots. The photocurable printing blank comprises a backing layer having at least one photocurable layer disposed thereon and a laser ablatable mask layer disposed on top of the at least one photocurable layer. The method includes: (1 ) imaging a photo curable layer by ablating the mask layer to create the relief pattern; (2) laminating an oxygen barrier membrane atop the ablated mask layer; (3) exposing the printing blank to actinic radiation through the oxygen barrier membrane and ablated mask layer to selectively crosslink and cure portions of the photocurable layer, thereby creating the relief pattern; (4) removing the oxygen barrier membrane from atop the ablated mask layer; and (5) thermally developing the printing blank to remove the ablated mask layer and uncured portions of the photo curable layer and reveal the relief pattern.
Abstract:
A method of making a relief image printing element from a photosensitive printing blank is described. The photosensitive printing blank comprises a laser ablatable mask layer disposed on at least one photocurable layer and the laser ablatable mask layer is selectively laser ablated to create an in situ mask and uncover portions of the at least one photocurable layer.
Abstract:
Photosensitive printing blank comprises a backing layer, at least one photocurable layer disposed on the backing layer, and a laser ablatable mask layer disposed on the at least one photocurable layer, wherein the laser ablatable mask layer is laser ablated to create an in situ negative in the laser ablatable mask layer, The exposing apparatus comprises: (a) a laminating apparatus for laminating an oxygen barrier layer to a top of the laser ablated mask layer; (b) a conveyor for conveying the photosensitive printing blank through the exposing apparatus; (c) a first exposing device for exposing the at least one photocurable layer to actinic radiation from the first exposing device through the laser ablated mask layer to selectively crosslink and cure portions of the at least one photocurable layer not covered by the mask layer, and (d) a second exposing device for exposing the at least one photocurable layer to actinic radiation.
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:
An apparatus for transferring a relief image printing blank between stations of a printing element manufacturing process and a method of using the same is described. The apparatus comprises a cylindrical mandrel for supporting the relief image printing element which includes means for securing the relief image printing blank to the mandrel. The mandrel is capable of transferring the relief image printing blank into and/or out of various stations of the printing element manufacturing process.
Abstract:
A method of tailoring the shape of a plurality of relief dots created in a photosensitive printing blank during a digital platemaking process is provided. The photosensitive printing blank comprises a laser ablatable mask layer disposed on at least one phoiocisrahle layer which is mountab!e on a printing sleeve. The method comprises the steps of (1) placing a barrier layer on top of the laser ablatable mask layer; (2) laser ablating the laser ablatable mask layer to create an in situ negative in the laser ablatable layer; (3) exposing the at least one photocurable layer to actinic radiation through the in situ negative; (4) removing the barrier layer; and (5) developing the imaged and exposed photosensitive printing blank to reveal the relief image therein, the relief image comprising the plurality of relief dots. The presence of the barrier layer produces printing dots having desired geometric characteristics.
Abstract:
A method of making a relief image printing element having a relief pattern, the method comprising the steps of: a) selectively ablating the masking layer to create an overall image in the masking layer, such that the overall image comprises a sub-image, comprising a pattern of cells, in it; b) applying an oxygen barrier layer on top of the masking layer; c) exposing the printing element to actinic radiation through the oxygen barrier layer and the masking layer to selectively crosslink: and cure the at least one photocurable layer, thereby creating the relief image therein and a textured surface on the printing element; and d) developing the printing blank by removing the barrier layer and the uncured portions of the photocmable layer to reveal the relief image.
Abstract:
A photocurable printing blank comprises a backing layer having a photocurable layer disposed thereon, a barrier layer disposed on the photocurable layer, and a laser ablatable mask layer disposed on top of the barrier layer. The method includes the steps of (1 ) imaging the at least one photo curable layer by ablating the laser ablatable mask layer to create the relief pattern on the photocurable printing blank; (2) exposing the printing blank to actinic radiation through the barrier layer and mask layer to selectively crosslink portions of the photocurable layer, thereby creating the relief pattern; (3) developing the printing blank to remove the barrier layer, the laser ablated mask layer and uncured portions of the photo curable layer and reveal the relief pattern. The method can also be used with an analog platemaking process that uses a negative instead of an ablatable mask layer.