Granted Patent B2

US 12,474,639 · App. 17/731,055 · Granted Nov 18, 2025

Inventors: Elsie Anderson Fohrenkamm (St. Paul, MN); Muluken N Taye (St. Paul, MN); Huiqun Wang (St. Paul, MN); Mohammad Zaki Ali (Mendota Heights, MN)

Assignee: MIRACLON CORPORATION

G03F7/11B41M1/04G03F7/0325G03F7/202G03F7/325

Abstract

Claims (28)

1 . A mask comprising:

a mask element, wherein the mask element includes:

a transparent polymeric carrier sheet that is devoid of an ultraviolet radiation absorbing compound;

a barrier layer on the transparent polymeric carrier sheet, wherein the barrier layer comprises non-crosslinked nitrocellulose and is devoid of an ultraviolet radiation absorbing compound; and

an imaging layer on the barrier layer, wherein the imaging layer includes a non-silver halide thermally-abatable material comprising non-crosslinked nitrocellulose, carbon black, and an infrared dye;

wherein the mask includes:

imaged regions in the imaging layer, wherein the imaged regions have optical apertures that are substantially devoid of the carbon black and the non-crosslinked nitrocellulose thereof; and

non-imaged regions in the imaging layer, wherein the non-imaged regions have the non-crosslinked nitrocellulose, carbon black, and infrared dye,

wherein the mask has an optical density of greater than or about 3.0 in the non-imaged region, and less than or about 0.20 in the imaged region.

2 . A relief-forming assembly comprising:

the mask of claim 1 ; and

a relief-forming precursor in complete optical contact with the mask.

3 . A method of making the mask of claim 1 , comprising:

providing the mask element without any imaged regions in the imaging layer; and

imaging the mask element with infrared light to form the imaged regions in the imaging layer.

4 . The method of claim 3 , wherein the imaging of the mask element results in the mask having an optical density of less than 0.20 for the imaged region.

5 . The method of claim 3 , wherein the imaging ablates the carbon black and non-crosslinked nitrocellulose in the imaging layer to form optical apertures for UV light.

6 . A method of forming a relief image, comprising:

providing a relief-forming assembly comprising a mask and a relief-forming precursor in complete optical contact with the mask, wherein the mask includes:

a transparent polymeric carrier sheet that is devoid of an ultraviolet radiation absorbing compound;

a barrier layer on the transparent polymeric carrier sheet, wherein the barrier layer comprises non-crosslinked nitrocellulose and is devoid of an ultraviolet radiation absorbing compound; and

an imaging layer on the barrier layer, wherein the imaging layer includes a non-silver halide thermally-ablatable material comprising non-crosslinked nitrocellulose having carbon black, and an infrared dye;

imaged regions in the imaging layer, wherein the imaged regions have optical apertures that are substantially devoid of the carbon black and non-crosslinked nitrocellulose thereof; and

non-imaged regions in the imaging layer, wherein the non-imaged regions have the non-crosslinked nitrocellulose, carbon black and infrared dye;

exposing a relief-forming layer of the relief-forming precursor to curing ultraviolet radiation through the mask to form an imaged relief-forming layer with ultraviolet-exposed regions forming polymerized regions and non-exposed regions forming non-polymerized regions in the imaged relief-forming layer, wherein the exposing is with the mask having an optical density greater than 3.0 in the non-imaged region, and less than 0.20 in the imaged region;

removing the mask from the imaged relief-forming layer; and

developing the imaged relief-forming layer by removing the non-polymerized regions in the imaged relief-forming layer, thereby forming a relief image element having a relief image.

7 . The method of claim 6 , wherein the exposing is performed to obtain a UV exposure that is from 17 Joules/cm 2 to 21 Joules/cm 2 .

Assignments (1)

Continuity (1)

References Cited (48)