# US 8,464,637 B2 · Method and apparatus for thermal development having a textured support surface > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,464,637 B2 - Document ID: US8464637B2 - Status: Granted - Kind: B2 - Application number: 12/786,051 - Filed: 2010-05-24 - Published: 2010-09-30 - Granted: 2013-06-18 - Earliest claimed: 2004-12-02 - Assignees: E. I. Du Pont de Nemours and Company - Applicants: Mark A. Hackler; David Anthony Belfiore; Dietmar Dudek; Anandkumar R. Kannurpatti; Andreas Koch - Inventors: Mark A. Hackler; David Anthony Belfiore; Dietmar Dudek; Anandkumar R. Kannurpatti; Andreas Koch - Web page: https://patentgrep.com/patent/US8464637B2 ## CPC - G03F 7/36: Imagewise removal not covered by groups G03F7/30 - G03F7/34, e.g. using gas streams, using plasma - G03F: PHOTOMECHANICAL PRODUCTION OF TEXTURED OR PATTERNED SURFACES, e.g. FOR PRINTING, FOR PROCESSING OF SEMICONDUCTOR DEVICES; MATERIALS THEREFOR; ORIGINALS THEREFOR; APPARATUS SPECIALLY ADAPTED THEREFOR; (phototypographic composing devices B41B; photosensitive materials or processes for photographic purposes G03C; electrophotography, sensitive layers or processes therefor G03G) ## Abstract The invention is a method and apparatus for forming a relief structure by thermally developing a photosensitive element containing a composition layer capable of being partially liquefied. During thermal development, the photosensitive element is supported on a base member having an exterior surface that is textured. The textures for the exterior surface include a particular surface roughness and/or patterns. ## Claims ### Claim 1 A method for forming a relief structure from a photosensitive element having an exterior surface and an interior surface and containing a composition layer capable of being partially liquefied comprising: supplying a development medium to the exterior surface with a first member; supporting the photosensitive element on a base member having an exterior surface, wherein the interior surface of the element is adjacent the exterior surface of the base member; and wherein the exterior surface of the base member defines a plane that is characterized by a plurality of surface projections from the plane, the exterior surface having a tack between 10 and 40 grams and a texture having a roughness, Rq, of at least 1 micron when measured over a 250 to 1000 micron length scale, wherein the combination of surface projections, tack and texture reduces air entrapment between the element and the base member, and allows for movement or slippage of the photosensitive element on the base member during relief structure formation, and wherein the method further comprises applying a layer of a modification material to the base member wherein the layer of material forms the exterior surface having texture, wherein the applying of the layer is with a texturing spray gun that both applies the layer and also renders the texture to the layer. ### Claim 2 (depends on 1) The method of claim 1 wherein the layer is resilient or tacky. ### Claim 3 (depends on 1) The method of claim 1 wherein the modification material is selected from the group consisting of natural rubbers, synthetic rubbers, and elastomers. ### Claim 4 (depends on 1) The method of claim 1 wherein the layer further comprises a roughening component. ### Claim 5 (depends on 1) The method of claim 1 wherein the base member is a selected from the group consisting of a drum, a roller, a platform member, a flexible support member, and a planar support. ### Claim 6 (depends on 1) The method of claim 1 further comprising placing a flexible support member between the base member and the element, wherein the flexible support member has a surface which is the exterior surface having texture. ### Claim 7 (depends on 6) The method of claim 6 further comprising applying a layer of a modification material to the flexible support member wherein the layer of material forms the exterior surface having texture. ### Claim 8 (depends on 6) The method of claim 6 further comprising adding at least one layer to the flexible support member selected from the group consisting of a resilient layer, a tacky layer, a protective layer, a resilient and tacky layer, and combinations thereof. ### Claim 9 (depends on 6) The method of claim 6 wherein the flexible support member comprises an aluminum sheet having a layer of silicone rubber on one side and a tacky layer on the silicone rubber layer, and wherein at least the tacky layer has texture. ### Claim 10 (depends on 1) The method of claim 1 wherein the surface roughness, Rq, is at least 1 micron when measured over a 250 to 750 micron length scale. ### Claim 11 (depends on 1) The method of claim 1 wherein the surface roughness, Rq, is at least 5 micron when measured over a 700 to 750 micron length scale. ### Claim 12 (depends on 1) The method of claim 1 further comprising applying a layer of an elastomeric material to the base member that forms the exterior surface of the base member and has the texture. ### Claim 13 (depends on 1) The method of claim 1 wherein the exterior surface defines a plane containing a plurality of projections and a plurality of pits that have a height relative to the plane, wherein an average height of the projections and pits is positive. ### Claim 14 (depends on 1) The method of claim 1 wherein the exterior surface defines a plane containing a plurality of projections and a plurality of pits, each having a height relative to the plane and a deviation from an average surface height, wherein at least 60% of a range of the deviations from the average height are projections above the average surface height. ### Claim 15 (depends on 1) The method of claim 1 wherein the exterior surface defines a plane containing a plurality of projections such that at least 60% of the surface is covered with projections. ### Claim 16 (depends on 1) The method of claim 1 further comprising heating the exterior surface of the element to a temperature sufficient to cause a portion of the layer to liquefy. ### Claim 17 The method of claim further comprising contacting the exterior surface of the photosensitive element with a development medium to allow at least a portion of the liquefied material of the composition layer to be absorbed by the development medium. ### Claim 18 (depends on 17) The method of claim 17 further comprising separating the photosensitive element from the development medium. ### Claim 19 (depends on 17) The method of claim 17 wherein the contacting comprises pressing the photosensitive element and the development medium into contact at a pressure sufficient for at least a portion of the liquefied material of the composition layer to be absorbed by the development medium. ### Claim 20 (depends on 1) The method of claim 1 further comprising heating the exterior surface of the element to a temperature sufficient to cause a portion of the layer to liquefy, wherein the heating is selected from the group consisting of a first heating which applies heat to an exterior surface of the composition layer adjacent where a development medium contacts the layer, the first heating adapted to heat the exterior surface of the layer; a second heating to heat the first member to a temperature capable of heating the exterior surface of the composition layer while the development medium is contacting the exterior surface of the layer; a third heating to heat the base member to a temperature capable of heating the exterior surface of the composition layer; combination of the first heating and the second heating; combination of the first heating and the third heating; combination of the second heating and the third heating; and combination of the first heating, the second heating, and the third heating, wherein the first heating, the second heating, and the third heating, individually or in the above combinations, is capable of heating the exterior surface of the composition layer sufficiently to cause a portion of the layer to liquefy. ### Claim 21 (depends on 1) The method of claim 1 wherein the exterior surface defines a plane that is characterized by a plurality of surface projections from the plane wherein the exterior surface has a density of projections of at least 0.1 projections/mm2 that are at least 10 microns in height above the plane. ### Claim 22 (depends on 21) The method of claim 21 wherein the projections have an average area of less than 5 mm2. ### Claim 23 (depends on 21) The method of claim 21 wherein the projections have an average area of 0.05-1 mm2. ### Claim 24 (depends on 1) The method of claim 1 wherein the exterior surface defines a plane containing a plurality of projections such that 15% of the surface or less is covered with projections. ### Claim 25 (depends on 1) The method of claim 1 wherein the texture is formed by an irregular pattern of a plurality of projections and a plurality of pits. ### Claim 26 A method for forming a relief structure from a photosensitive element having an exterior surface and an interior surface and containing a composition layer capable of being partially liquefied comprising: supplying a development medium to the exterior surface with a first member; supporting the photosensitive element on a base member having an exterior surface, wherein the interior surface of the element is adjacent the exterior surface of the base member; and wherein the exterior surface of the base member defines a plane that is characterized by a plurality of surface projections from the plane, the exterior surface having a tack between 10 and 40 grams and a texture with a surface roughness, Rq, of at least 3 micron when measured over a 500 to 3000 micron length scale, wherein the combination of surface projections, tack and texture reduces air entrapment between the element and the base member, and allows for movement or slippage of the photosensitive element on the base member during relief structure formation, and wherein the method further comprises applying a layer of a modification material to the base member wherein the layer of material forms the exterior surface having texture, wherein the applying of the layer is with a texturing spray gun that both applies the layer and also renders the texture to the layer. ### Claim 27 (depends on 26) The method of claim 26 wherein the surface roughness, Rq, is at least 5 micron when measured over a 700 to 3000 micron length scale. ### Claim 28 (depends on 26) The method of claim 26 wherein the surface roughness, Rq, is 3 to 25 micron when measured over a 700 to 3000 micron length scale. ### Claim 29 (depends on 26) The method of claim 26 wherein the surface roughness, Rq, is 5 to 15 micron when measured over a 700 to 3000 micron length scale. ### Claim 30 An apparatus for forming a relief structure from a photosensitive element having an exterior surface and an interior surface and containing a composition layer capable of being partially liquefied comprising: means for supplying a development medium to the exterior surface with a first member; a base member for supporting the photosensitive element, wherein the interior surface of the element is adjacent an exterior surface of the base member; and wherein the exterior surface of the base member defines a plane that is characterized by a plurality of surface projections from the plane, the exterior surface having a tack between 10 and 40 grams and a texture having a roughness, Rq, of at least 1 micron when measured over a 250 to 1000 micron length scale; wherein the combination of surface projections, tack and texture reduces air entrapment between the element and the base member, and allows for movement or slippage of the photosensitive element on the base member during relief structure formation; and wherein the base member is coated with a layer of a modification material that forms the exterior surface having texture, wherein the layer of modification is applied to the base member with a texturing spray gun that both applies the layer and also renders the texture to the layer. ### Claim 31 (depends on 30) The apparatus of claim 30 wherein the layer is resilient or tacky. ### Claim 32 (depends on 30) The apparatus of claim 30 wherein the modification material is selected from the group consisting of natural rubbers, synthetic rubbers, and elastomers. ### Claim 33 (depends on 30) The apparatus of claim 30 wherein the base member is a selected from the group consisting of a drum, a roller, a platform member, a flexible support member, and a planar support. ### Claim 34 (depends on 30) The apparatus of claim 30 further comprising a flexible support member between the base member and the element, wherein the flexible support member has a surface which is the exterior surface having texture. ### Claim 35 (depends on 34) The apparatus of claim 34 further comprising a layer of a modification material on the flexible support member on a side opposite the base member, wherein the layer of material forms the exterior surface having texture. ### Claim 36 (depends on 35) The apparatus of claim 35 wherein the layer is selected from the group consisting of a resilient layer, a tacky layer, a protective layer, a resilient and tacky layer, and combinations thereof. ### Claim 37 (depends on 34) The apparatus of claim 34 wherein the flexible support member comprises an aluminum sheet having a layer of silicone rubber on one side and a tacky layer on the silicone rubber layer, and wherein at least the tacky layer has texture. ### Claim 38 (depends on 30) The apparatus of claim 30 wherein the surface roughness, Rq, is at least 1 micron when measured over a 250 to 750 micron length scale. ### Claim 39 (depends on 30) The apparatus of claim 30 wherein the surface roughness, Rq, is at least 5 micron when measured over a 700 to 750 micron length scale. ### Claim 40 (depends on 30) The apparatus of claim 30 wherein the exterior surface defines a plane containing a plurality of projections and a plurality of pits that each have a height relative to the plane which determine an average height, wherein the average height of the projections and pits is positive. ### Claim 41 (depends on 30) The apparatus of claim 30 wherein the exterior surface defines a plane containing a plurality of projections and a plurality of pits, each having a height relative to the plane and a deviation from an average surface height, wherein at least 60% of a range of the deviations from the average height are projections above the average surface height. ### Claim 42 (depends on 30) The apparatus of claim 30 further comprising means for heating the exterior surface of the element to a temperature sufficient to cause a portion of the layer to liquefy. ### Claim 43 (depends on 30) The apparatus of claim 30 further comprising means for contacting the exterior surface of the photosensitive element with a development medium to allow at least a portion of the liquefied material of the composition layer to be absorbed by the development medium. ### Claim 44 (depends on 30) The apparatus of claim 30 further comprising means for separating the photosensitive element from the development medium. ### Claim 45 (depends on 30) The apparatus of claim 30 further comprising means for pressing the photosensitive element and the development medium into contact at a pressure sufficient for at least a portion of the liquefied material of the composition layer to be absorbed by the development medium.