Imaging element for use as a recording element and process of using the imaging element

Abstract

The invention relates to an imaging element and a method of using the imaging element to form a recording element. The imaging element includes a composition sensitive to actinic radiation at a first wavelength and a photoluminescent tag that is responsive to radiation at a second wavelength different from the first wavelength. The photoluminescent tag can be used to authenticate the identity of the element, provide information about the element, and/or to establish one or more conditions in a device used to prepare the recording element from the imaging element.

1 . An imaging element comprising a composition sensitive to actinic radiation at a first wavelength, wherein a photoluminescent tag is disposed in the element, the tag being responsive to radiation at a second wavelength different from the first wavelength.  
   
   
       2 . The imaging element of  claim 1  wherein the composition is a photosensitive composition.  
   
   
       3 . The imaging element of  claim 2  wherein the tag is disposed in the photosensitive composition.  
   
   
       4 . The imaging element of  claim 1  wherein the composition is a photosensitive composition comprising a monomer and an initiator or initiator system sensitive to actinic radiation at the first wavelength.  
   
   
       5 . The imaging element of  claim 4  wherein the photosensitive composition further comprises a binder.  
   
   
       6 . The imaging element of  claim 5  wherein the binder is an elastomeric binder.  
   
   
       7 . The imaging element of  claim 1  wherein the tag responds to excitation or stimulation at the second wavelength.  
   
   
       8 . The imaging element of  claim 1  wherein the tag responds by emitting at a third wavelength.  
   
   
       9 . The imaging element of  claim 1  wherein the tag is an inorganic compound.  
   
   
       10 . The imaging element of  claim 1  wherein upon exposure to radiation at the second wavelength, the tag can fluorescence, or phosphorescence, or have stimulated emission.  
   
   
       11 . The imaging element of  claim 1  wherein the tag becomes excited or stimulated in response to exposure to radiation at the second wavelength, and generates emitted radiation at a third wavelength that is different from the first wavelength and the second wavelength.  
   
   
       12 . The imaging element of  claim 1  wherein the tag is a metal oxysulfide phosphor.  
   
   
       13 . The imaging element of  claim 1  wherein the tag is present in the composition in an amount of 1 to 1000 parts per million based on the total amount of the composition.  
   
   
       14 . The imaging element of  claim 13  wherein the tag is present in the composition in an amount of 1 to 300 parts per million based on the total amount of the composition.  
   
   
       15 . The imaging element of  claim 1  further comprising at least one additional layer adjacent a first layer of the composition, the additional layer selected from the group consisting of a support layer, a release layer, a second composition layer sensitive to actinic radiation at the first wavelength, an elastomeric layer capable of becoming sensitive to actinic radiation at the first wavelength, a wax layer, an adhesion modifying layer, a laser-radiation sensitive layer, a coversheet, and combinations thereof.  
   
   
       16 . The imaging element of  claim 15  wherein the tag is disposed in the at least one additional layer.  
   
   
       17 . The imaging element of  claim 15  wherein the laser-radiation sensitive layer is sensitive to infrared laser radiation.  
   
   
       18 . The imaging element of  claim 1  wherein the tag is dispersed in a polymer forming a layer adjacent a layer of the composition.  
   
   
       19 . The imaging element of  claim 1  wherein the imaging element upon exposure to the actinic radiation becomes a recording element.  
   
   
       20 . The imaging element of  claim 19  wherein the recording element is a flexographic printing form.  
   
   
       21 . The imaging element of  claim 19  wherein the recording element is a pre-press proof.  
   
   
       22 . The imaging element of  claim 19  wherein the recording element is a thermally-formed color filter.  
   
   
       23 . The imaging element of  claim 19  wherein the recording element is a photoresist.  
   
   
       24 . The imaging element of  claim 19  wherein the recording element is a letterpress printing form.  
   
   
       25 . The imaging element of  claim 1  wherein the composition forms a photosensitive layer comprising at least one monomer, a photoinitiator or initiator system sensitive to the actinic radiation at the first wavelength, and the tag.  
   
   
       26 . The imaging element of  claim 1  further comprising at least one additional photoluminescent tag responsive to radiation at a wavelength different from the first wavelength and different from the second wavelength.  
   
   
       27 . The imaging element of  claim 1  wherein the first wavelength is between 250 to 400 nm.  
   
   
       28 . The imaging element of  claim 1  wherein the second wavelength is greater than 400 nm.  
   
   
       29 . The imaging element of  claim 1  wherein the second wavelength is between 800 to 1200 nm.  
   
   
       30 . The imaging element of  claim 1  wherein the tag responds by emitting at a third wavelength between 450 and 600 nm.  
   
   
       31 . The imaging element of  claim 1  wherein the tag is an anti-stokes phosphor.  
   
   
       32 . The imaging element of  claim 1  wherein the tag is present in the composition in an amount of 25 to 250 parts per million based on the total amount of the composition.  
   
   
       33 . The imaging element of  claim 1  wherein the composition sensitive to actinic radiation forms a layer and the imaging element further comprises a release layer disposed above the composition layer, and the tag is present in the release layer.  
   
   
       34 . The imaging element of  claim 1  wherein the composition sensitive to actinic radiation forms a layer adjacent a support and the tag is present in the support.  
   
   
       35 . A method for making a recording element comprising: 
 a) providing an imaging element comprising a layer of a composition sensitive to actinic radiation at a first wavelength, wherein a photoluminescent tag is disposed in the element, the tag being responsive to radiation at a second wavelength different from the first wavelength;    b) exposing the imaging element to the actinic radiation; and    c) treating the element of b) to form the recording element.    
   
   
       36 . The method of  claim 35  wherein the tag is disposed in the composition.  
   
   
       37 . The method of  claim 35  wherein the composition is a photosensitive composition comprising at least one monomer and an initiator or initiator system sensitive to actinic radiation at the first wavelength.  
   
   
       38 . The method of  claim 35  wherein the composition further comprises a binder.  
   
   
       39 . The method of  claim 35  wherein the composition further comprises an elastomeric binder.  
   
   
       40 . The method of  claim 35  wherein the tag is responsive by excitation at the second wavelength.  
   
   
       41 . The method of  claim 35  wherein the tag is responds to excitation or stimulation at the second wavelength.  
   
   
       42 . The method of  claim 35  wherein the tag responds by emitting at a third wavelength.  
   
   
       43 . The method of  claim 35  wherein upon exposing to radiation at the second wavelength, the tag can fluorescence, or phosphorescence, or have stimulated emission.  
   
   
       44 . The method of  claim 35  further comprising exposing the element to radiation at the second wavelength.  
   
   
       45 . The method of  claim 44  wherein the tag responds to radiation at the second wavelength by generating emitted radiation at a third wavelength that is different from the first wavelength and the second wavelength.  
   
   
       46 . The method of  claim 45  wherein the third wavelength is between 450 to 600 nm.  
   
   
       47 . The method of  claim 35  wherein the first wavelength is between 250 to 400 nm.  
   
   
       48 . The method of  claim 35  wherein the second wavelength is between 800 to 1200 nm.  
   
   
       49 . The method of  claim 35  further comprising exposing the element to radiation at the second wavelength, wherein the tag can fluoresce, or phosphoresce, or have stimulated emission.  
   
   
       50 . The method of  claim 35  wherein the imaging element further comprises at least one additional layer on or adjacent the layer of the composition, selected from the group consisting of a support, a release layer, a second composition layer sensitive to actinic radiation at the first wavelength, an elastomeric layer capable of becoming sensitive to actinic radiation at the first wavelength, a wax layer, an adhesion modifying layer, a laser-radiation sensitive layer, a coversheet, and combinations thereof.  
   
   
       51 . The method of  claim 50  wherein the tag is disposed in the at least one additional layer.  
   
   
       52 . The method of  claim 50  wherein the imaging element further comprises a laser radiation sensitive layer disposed on or adjacent a layer of the composition, the method further comprising exposing the imaging element to infrared laser radiation prior to the treating step to form an in-situ mask on the composition layer.  
   
   
       53 . The method of  claim 52  wherein the infrared laser radiation is greater than 770 nm.  
   
   
       54 . The method of  claim 35  wherein the tag is dispersed in a polymer forming a layer adjacent a layer of the composition.  
   
   
       55 . The method of  claim 35  wherein the exposure step b) is selected from the group consisting of: 
 (1) imagewise exposing a layer of the composition with the actinic radiation to form exposed areas and unexposed areas; and    (2) blanket exposing a layer of the composition with the actinic radiation.    
   
   
       56 . The method of  claim 55  wherein the imagewise exposing step is selected from the group consisting of 
 (1) exposing the composition layer with the actinic radiation through a phototool;    (2) imagwise exposing a laser-radiation sensitive layer on or adjacent the composition layer to laser radiation at least different from the first wavelength to form an in-situ mask above the composition layer, and exposing the composition layer with the actinic radiation through the in-situ mask; and    (3) imagewise applying an actinic radiation opaque material on or above the composition layer to form a mask, and exposing the composition layer with the actinic radiation through the mask.    
   
   
       57 . The method of  claim 56  wherein the imagewise exposing is with laser radiation different from the second wavelength.  
   
   
       58 . The method of  claim 35  wherein the composition forms a photosensitive layer comprising at least one monomer, a photoinitiator or initiator system sensitive to the actinic radiation at the first wavelength, and the tag.  
   
   
       59 . The method of  claim 35  wherein the imaging element further comprises at least one additional photoluminescence tag responsive to radiation at a wavelength different from the first wavelength and different from the second wavelength.  
   
   
       60 . The method of  claim 35  wherein the treating step c) is selected from the group consisting of 
 (1) processing the element of step b) with at least one washout solution selected from the group consisting of solvent solution, aqueous solution, semi-aqueous solution and water;    (2) heating the element of step b) to a temperature sufficient to cause areas to melt, flow, or soften;    (3) separating the composition layer of the element of step b) from a layer adjacent the composition layer or from a coversheet above the composition layer;    (4) laminating the composition layer of the element of step b) to a support or a substrate; and    (5) transferring the composition layer of the element of step b) to a support, receptor, or display sheet.    
   
   
       61 . The method of  claim 60  wherein after heating the element in step (2) the method further comprises contacting the element with a development medium to remove the areas that melt, flow, or soften.  
   
   
       62 . The method of  claim 60  wherein the treating steps (1) and (2) form a relief surface suitable for printing.  
   
   
       63 . The method of  claim 35  wherein the composition is a photosensitive composition forming a layer and the exposing step b) comprises blanket exposing the layer to the actinic radiation sufficient to photoreinforce the layer overall to a depth; and 
 wherein the treating step c) comprises imagewise exposing the photoreinforced layer of the element of step b) to laser radiation at a laser wavelength different from the first wavelength to remove portions of the photoreinforced layer to a depth.    
   
   
       64 . The method of  claim 62  wherein the laser radiation is between 760 and 1200 nm.  
   
   
       65 . The method of  claim 62  wherein the laser radiation is between 10 to 11 microns.  
   
   
       66 . The method of  claim 35  wherein the treating step c) comprises forming a relief surface.  
   
   
       67 . A method for setting conditions in a device used for making a recording element comprising: 
 a) providing an imaging element comprising a layer of a composition sensitive to actinic radiation at a first wavelength, wherein a photoluminescent tag is disposed in the element, the tag being responsive to radiation at a second wavelength different from the first wavelength;    b) exposing the element to radiation at the second wavelength to excite or stimulate the tag and create an emission from the tag;    c) detecting the emission; and    d) setting one or more conditions for operation of the device according to the detected emission from step c).    
   
   
       68 . The method of  claim 67  wherein the emission from the tag is at a third wavelength.  
   
   
       69 . The method of  claim 67  further comprising scanning the element with a detection system which conducts the steps of exposing to the second wavelength and detecting the emission from the excited tag.  
   
   
       70 . The method of  claim 69  wherein the detection system is located remote from the device for making the recording element or is located on the device for making the recording element.  
   
   
       71 . The method of  claim 67  wherein the setting step comprises: 
 d1) translating the detected emission of step c) into a coded signal;    d2) interpreting the coded signal; and    d3) responding to the interpreted signal by establishing one or more of the conditions for the operation of the device.    
   
   
       72 . The method of  claim 71  wherein the responding step further comprises recording the response.  
   
   
       73 . The method of  claim 71  wherein the responding step further comprises comparing one or more of the conditions against a corresponding baseline set point and/or range; and determining if one or more of the conditions is changed.  
   
   
       74 . The method of  claim 67  wherein the device is operating at a first condition and the setting step changes the first condition to a second condition.  
   
   
       75 . The method of  claim 67  wherein the device is operating at a first set of conditions and the responding step changes one or more of the conditions in the first set to a second set of conditions.  
   
   
       76 . The method of  claim 67  wherein the device is selected from the group consisting of an actinic radiation exposure unit; a laser radiation exposure unit; washout processor; a thermal processor; a post-exposure unit; a finishing exposure unit; and a laminator.  
   
   
       77 . The method of  claim 76  wherein the device is the thermal processor for heating the imaging element to a temperature sufficient to cause areas to melt, flow, or soften, and the conditions for the thermal processor are selected from the group consisting of a rotation speed of a drum roll, a rotation speed of a developer hot roll, temperature of the developer hot roll, power to additional heating devices, pressure of the developer hot roll on the imaging element, and combinations thereof.  
   
   
       78 . The method of  claim 76  wherein the device is the washout processor for removing portions of a layer of the composition with a treating solution, and the conditions for the washout processor are selected from the group consisting of temperature of the treating solution, pressure of a brush or brushes, rotation speed of the brush or brushes, transport speed of the imaging element, and combinations thereof.  
   
   
       79 . The method of  claim 76  wherein the device is a laser radiation exposure unit for forming image on the imaging element, and the conditions for the laser radiation exposure unit are selected from the group consisting of focal point of the laser radiation, power of the laser radiation, wavelength of the laser radiation, number of beams of laser radiation, number of laser heads, transport speed of the imaging element, scanning speed of the laser radiation, and combinations thereof.  
   
   
       80 . The method of  claim 76  wherein the device is the laminator for forming an assemblage of a secondary element with the imaging element and the conditions are selected from the group consisting of pressure of a lamination roller, temperature of the lamination roller, transport speed of the imaging element, and combinations thereof.  
   
   
       81 . The method of  claim 76  wherein the device is the actinic radiation exposure unit for exposing the imaging element to the actinic radiation, and the conditions are selected from the group consisting of time of exposure, energy density of the actinic radiation, wavelength of the actinic radiation, and combinations thereof.  
   
   
       82 . The method of  claim 67  wherein the device further comprises one or more sensors for detecting emission of the tag.  
   
   
       83 . The method of  claim 67  wherein the device further comprises one or more sources of radiation at the second wavelength for exciting or stimulating the tag.  
   
   
       84 . A flexographic printing form prepared according to the method of  claim 35.