Provided are methods of imaging a wet positive working lithographic printing member comprising the steps of providing a positive working printing member comprising a substrate, a hydrophilic layer, an infrared-absorbing layer, and, optionally, an ink-accepting surface layer; exposing the printing member to infrared layer imaging in an imagewise pattern removing by ablation not greater than 10% by weight, and most preferably none of the infrared-absorbing layer and optional ink-accepting surface layer; and removing with water the laser-exposed areas of the infrared-absorbing layer and optional ink-accepting surface layer to reveal the underlying hydrophilic layer. These methods are advantageous in reducing airborne debris and vapors during laser imaging, in increasing the speed of laser imaging, and in providing excellent cleanability and image quality. The printing member may further comprise a primer layer underlying the infrared-absorbing layer with an adhesion-promoting agent present in the primer layer. Also provided are methods of preparing a wet lithographic printing member and wet positive working lithographic printing members prepared according to the methods of this invention.

The present invention relates in general to lithography and more particularly to systems for preparing lithographic printing plates using digitally controlled laser output. More specifically, this invention relates to methods for preparing a lithographic printing plate especially suitable for directly imaging and utilizing with a wet lithographic printing press. The present invention also pertains to wet lithographic printing plates prepared according to such methods.
Traditional techniques for introducing a printed image onto a recording material include letterpress printing and offset lithography. Both of these printing methods require a plate. To transfer ink in the pattern of the image, the plate is usually loaded onto a plate cylinder of a rotary press for efficiency. In letterpress printing, the image pattern is represented on the plate in the form of raised areas that accept ink and transfer it onto the recording medium by impression. The term xe2x80x9clithographic,xe2x80x9d as used herein, is meant to include various terms used synonymously, such as offset, offset lithographic, planographic, and others. By the term xe2x80x9cwet lithographic,xe2x80x9d as used herein, is meant the type of lithographic printing plate where the printing is based upon the immiscibility of oil and water, wherein the oily material or ink is preferentially retained by the image area and the water or fountain solution is preferentially retained by the non-image area. When a suitably prepared surface is moistened with water and an ink is then applied, the background or non-image area retains the water and repels the ink while the image area accepts the ink and repels the water. The ink on the image area is then transferred to the surface of a material upon which the image is to be reproduced, such as paper, cloth, and the like. Commonly the ink is transferred to an intermediate material called the blanket, which in turn transfers the ink to the surface of the material upon which the image is to be reproduced. In a dry lithographic printing system that does not utilize water, the plate is simply inked and the image transferred directly onto a recording material or transferred onto a blanket and then to the recording material.
Aluminum has been used for many years as a support for lithographic printing plates. In order to prepare the aluminum for such use, it is typically subject to both a graining process and a subsequent anodizing process. The graining process serves to improve the adhesion of the image to the plate and to enhance the water-receptive characteristics of the background areas of the printing plate. The graining and anodizing affect both the performance and the durability of the printing plate. Both mechanical and electrolytic graining processes are well known and widely used in the manufacture of lithographic printing plates. Processes for anodizing aluminum to form an anodic oxide coating and then hydrophilizing the anodized surface by techniques such as silication are also well known in the art, and need not be further described herein. The aluminum support is thus characterized by having a porous, wear-resistant hydrophilic surface, which specifically adapts it for use in lithographic printing, particularly where long press runs are required.
The plates for a lithographic press are usually produced photographically. The aluminum substrate described above is typically coated with a wide variety of photo-sensitive materials suitable for forming images for use in the lithographic printing process. Lithographic printing plates of this type are usually developed with an aqueous alkaline developing solution, which often additionally comprises a substantial quantity of an organic solvent.
To prepare a wet plate using a typical negative-working subtractive process, the original document is photographed to produce a photographic negative. This negative is placed on an aluminum plate having a water-receptive oxide surface coated with a photopolymer. Upon exposure to light or other radiation through the negative, the areas of the coating that received radiation (corresponding to the dark or printed areas of the original) cure to a durable oleophilic state. The plate is then subjected to a developing process that removes the uncured areas of the coating (i.e., those which did not receive radiation, corresponding to the non-image or background areas of the original), thereby exposing the hydrophilic surface of the aluminum plate.
Throughout this application, various publications, patents, and published patent applications are referred to by an identifying citation. The disclosures of the publications, patents, and published patent applications referenced in this application are hereby incorporated by reference into the present disclosure to more fully describe the state of the art to which this invention pertains.
As is evident from the above description, photographic platemaking processes tend to be time consuming and require facilities and equipment adequate to support the necessary chemistry. Efforts have been made for many years to manufacture a printing plate, which does not require aqueous alkaline or solvent development or which only uses water for development. In addition, practitioners have developed a number of electronic alternatives to plate imaging, some of which can be utilized on-press. With these systems, digitally controlled devices alter the ink-receptivity of blank plates in a pattern representative of the image to be printed. Such imaging devices include sources of electromagnetic radiation, produced by one or more laser or non-laser sources, that create physical and/or chemical changes on plate blanks; ink jet equipment that directly deposits ink-repellent or ink-accepting spots on plate blanks; and spark-discharge equipment, in which an electrode in contact with or spaced closely to a plate blank produces electrical sparks to physically alter the topology of the plate blank, thereby producing xe2x80x9cdotsxe2x80x9d which collectively form a desired image as for example, described in U.S. Pat. No. 4,911,075. Because of the ready availability of laser equipment and its amenability to digital control, significant effort has been devoted to the development of laser-based imaging systems.
In one such system, argon-ion, frequency-doubled Nd-YAG, and other infrared lasers are used to expose photosensitive blanks for traditional chemical processing, as for example described in U.S. Pat. Nos. 3,506,779; 4,020,762; 4,868,092; 5,153,236; 5,372,915; and 5,629,354. In an alternative to this approach, a laser has been employed to selectively remove, in an imagewise pattern, an opaque coating that overlies a photosensitive plate blank. The plate is then exposed to a source of radiation, with the unremoved material acting as a mask that prevents radiation from reaching underlying portions of the plate, as for example described in U.S. Pat No. 4,132,168. However, the need for high writing speeds, coupled with the constraint of the low-powered lasers favored by industry, has resulted in a requirement for printing plates that have a very high photosensitivity. Unfortunately, high photosensitivity almost always reduces the shelf life of these plates.
Another approach to laser imaging uses thermal-transfer materials, as for example described in U.S. Pat. Nos. 3,945,318; 3,962,513; 3,964,389; 4,395,946; and 5,395,729. With these systems, a polymer sheet transparent to the radiation emitted by the laser is coated with a transferable material. The transfer side of this construction is brought into contact with an acceptor sheet, and the transfer material is selectively irradiated through the transparent layer. Irradiation causes the transfer material to adhere preferentially to the acceptor sheet. The transfer and acceptor materials exhibit different affinities for fountain solution and/or ink, so that removal of the transparent polymer sheet with the unirradiated transfer material still on it leaves a suitably imaged, finished plate. Typically, the transfer material is oleophilic, and the acceptor material is hydrophilic. Plates produced with transfer type systems tend to exhibit short useful lifetimes due to the limited amount of material that can effectively be transferred: Airborne dirt can create an image quality problem depending on the particular construction. In addition, because the transfer process involves melting and resolidification of material, image quality further tends to be visibly poorer than that obtainable with other methods.
Other patents describe lithographic printing plates comprising a support and a hydrophilic imaging layer which, upon imagewise laser exposure, becomes oleophilic in the exposed areas while remaining hydrophilic in the unexposed areas, as for example disclosed in U.S. Pat. Nos. 3,793,033, 4,034,183; 4,081,572; and 4,693,958. However, these types of lithographic printing plates suffer from the lack of a sufficient degree of discrimination between oleophilic image areas and hydrophilic non-image areas, with the result that image quality on printing is poor.
Early examples utilizing lasers used the laser to etch away material from a plate blank to form an intaglio or letterpress pattern, as for example described in U.S. Pat. Nos. 3,506,779 and 4,347,785. This approach was later extended to production of lithographic plates, e.g., by removal of a hydrophilic surface to reveal an oleophobic underlayer, as for example described in U.S. Pat. No. 4,054,094. These early systems generally required high-power lasers, which are expensive and slow.
Other infrared laser ablation-based systems for imaging lithographic plates have been developed. These operate by laser-induced ablative removal of organic coating layers, which are coated onto a substrate such as a polyester/metal laminate or onto a polymer coating on a metal support. Use of these polyester or polymer coating materials between the ablation coating and the heat absorbing metal support provides a thermal barrier material which reduces the amount of laser energy required to ablate or fully remove the ablative-absorbing layer and any overlying surface layer, as for example described in Canadian Pat. No. 1,050,805 and in U.S. Pat. Nos. 5,339,737; and 5,353,705. The laser exposure thus removes one or more plate layers, resulting in an imagewise pattern of features on the plate. When the layers removed by laser ablation are the image regions that accept ink, the plates are negative working. When lasers with a large spot size are used for imaging a negative working plate, the size of the smallest printed dot is about as large as the spot size. Consequently, the image quality on printing may not be high. For example, a 35 micron laser spot size would print its smallest dot size at about 35 microns with a negative working plate. On a 200 lines per inch (lpi) halftone screen, this is equivalent to a 5% to 6% dot.
U.S. Pat. No. 5,353,705 discloses a basic plate construction of a lithographic plate having a secondary ablation layer intermediate between a substrate and a surface layer, such as a hydrophilic metal substrate and a radiation-absorptive and ablatively absorbing surface layer. The secondary ablation layer performs the protective or thermal barrier function that shields the substrate from the thermal effects of imaging radiation. The secondary ablation or thermal barrier layer of the ""705 patent is ablated only partially in response to ablation of the ablative-absorbing layer, is preferably substantially transparent to the laser radiation and thereby not characterized by ablative absorption of imaging radiation, and differs from the surface layer in its affinity for at least one printing fluid selected from the group consisting of ink and a fluid that repels ink, i.e., when the surface layer is ink-receptive and/or not receptive to a fountain solution, the thermal barrier layer is not ink-receptive and/or is receptive to a fountain solution, respectively. When the basic plate construction described in the ""705 patent has an ink receptive surface layer, and the thermal barrier or secondary ablation layer is receptive to a fountain solution and thus is not ink receptive, a positive working, wet lithographic plate results since the portions not removed by ablation are the image regions that accept ink. Suitable polymeric materials for the secondary ablation layer of the ""705 patent include, but are not limited to, polymethyl methacrylates, cellulosic ethers and esters, polyesters, and polyurethanes. Hexamethoxymethylmelamine with p-toluenesulfonic acid may be added to these polymeric materials.
U.S. Pat. No. 5,493,971 describes an example of such a positive working, wet lithographic plate. Its plate construction includes a hydrophilic metal substrate, a polymeric, hydrophilic protective or thermal barrier coating which also may serve as an adhesion-promoting primer, and an ink-accepting oleophilic surface layer characterized by ablative absorption of imaging radiation. The imaging laser interacts with the ablatable surface layer, causing ablation thereof. After laser ablation imaging which removes at least the surface layer and also at least some of the hydrophilic protective layer as shown in FIG. 2 of the ""971 patent, the plate is then cleaned with a suitable solvent, e.g., water, to remove portions of the hydrophilic protective layer still remaining in the laser-exposed areas. Since the hydrophilic protective layer is partially ablated in the ""971 patent, but is not characterized by ablative absorption of imaging radiation, this hydrophilic protective layer must not absorb the laser imaging radiation. It is thus similar to the secondary ablation layer of the ""705 patent which is partially ablated and may be substantially transparent to the laser imaging radiation and thus not characterized by ablative absorption of the surface layer. In the ""971 patent, depending on the solubility properties of the residual plug of the partially ablated hydrophilic protective layer in the cleaning solvent, e.g., water, the cleaning step reveals the hydrophilic protective coating at less than its original thickness, or reveals the hydrophilic metal substrate in the areas where the hydrophilic protective coating is entirely removed by the cleaning step. After cleaning, the plate behaves like a conventional positive working wet lithographic metal plate on the printing press.
However, adhesion of the remaining ink-accepting surface coating to the hydrophilic protective layer has proven a difficult problem to overcome. Loss of adhesion can result if the protective hydrophilic thermal barrier layer in the image or printing areas of the plate is damaged or degraded during the laser imaging and cleaning process of the ""971 patent. For example, too much solvent or solubilization action by the cleaning solution or the fountain solution on press may erode the walls of the image areas, eliminating the underlying support provided by the hydrophilic barrier layer around the periphery of the image feature and degrading small image elements. This is particularly problematical when the hydrophilic protective coating layer is partially ablated and probably further removed by the cleaning step and the action of the fountain solution such that the original surface of this protective coating layer is removed. This fully exposes the interface between the ink-accepting layer and the hydrophilic protective coating layer, as well as some of the wall of the hydrophilic protective coating layer at the edge of the image feature, to these wet cleaning and fountain solutions. This may lead to a major loss of image quality. Small dots and type may be removed during the cleaning step or early in the print run. Efforts to improve the adhesion of the laser ablatable surface coating and/or its durability to permit longer printing runs typically leads to a significant increase in the laser energy required to image the plate. International Publication No. WO 99/37481 discloses novel positive working, wet lithographic printing plates and methods for preparing such lithographic printing plates, which overcome this adhesion problem.
U.S. Pat. No. 5,605,780 describes a laser-ablatable lithographic printing plate comprising an anodized aluminum support having thereon an oleophilic image-forming layer comprising an infrared-absorbing agent dispersed in a film-forming cyanoacrylate polymer binder. The hydrophilic protective layer has been eliminated. The ""780 patent describes low required laser energy, good ink receptivity, good adhesion to the support, and good wear characteristics. Print runs of more than 8200 impressions are shown in the examples.
U.S. Pat. No. 5,339,737 and Reissue Pat. No. 35,512 describe a variety of ablation-type lithographic plate configurations for use with laser diode imaging apparatus. These configurations include an ablation layer, which volatilizes into gaseous and particulate debris in response to infrared imaging radiation. As used herein, the term xe2x80x9cablationxe2x80x9d refers to the volatilization of a layer or a material into gaseous and particulate debris in response to imaging radiation, which ablation results in a loss of mass or weight in the layer or material. For example, U.S. Pat. No. 5,493,971 describes a complete or 100% ablative loss of the ablative layer during the laser ablation imaging process, and FIG. 3A of International Publication No. WO 99/37481 describes a partial ablative loss of about 50% or greater of the ablatable layer during the laser ablation imaging process.
Lithographic printing members are now commonly imaged by lower-power laser ablation imaging mechanisms. A major problem with these infrared laser ablation-based systems for imaging lithographic plates has been environmental. Because these operate by laser-induced destruction or removal of organic polymers and other organic or inorganic materials which are coated in one or more layers overlying a substrate, airborne debris and vapors are produced during imaging which may be hazardous to the laser equipment and to the personnel who operate the equipment. Expensive equipment is generally required to contain the debris and to capture the gases.
Despite the many efforts directed to the development of a laser imageable wet lithographic printing plate, there still remains a need for plates that require no alkaline or solvent developing solution, that perform like a conventional lithographic printing plate on press, that are sensitive to a broad spectrum of laser energy such as 700 nm to 1150 nm, that provide a high resolution and durable image, and that do not produce debris and vapor requiring expensive and complex containment equipment.
One aspect of the present invention pertains to methods of imaging a wet lithographic printing member, which methods comprise the steps of (a) providing a positive working lithographic printing member, which positive working member comprises a substrate, a hydrophilic layer overlying the substrate, and an ink-accepting and infrared-absorbing surface layer overlying the hydrophilic layer; wherein the surface layer is characterized by absorption of infrared imaging radiation, by being not removable by cleaning with water or a cleaning solution prior to the absorption of infrared imaging radiation, and by being adapted to form a wet lithographic printing surface as a result of an imagewise exposure to absorbable infrared radiation and subsequent removal of the exposed areas of the surface layer by cleaning with water or the cleaning solution to reveal the underlying hydrophilic layer; and the hydrophilic layer is characterized by being not removable by cleaning with water or the cleaning solution; (b) exposing the positive working member of step (a) to absorbable infrared radiation using an infrared-emitting laser to effect absorption of infrared radiation in the laser-exposed areas of the surface layer that is sufficient to cause the surface layer in the laser-exposed areas to become removable by cleaning with water or the cleaning solution but insufficient to remove by ablation greater than 10% by weight of the surface layer material in the laser-exposed areas; and (c) removing, with water or the cleaning solution, the laser-exposed areas of the surface layer to reveal the underlying hydrophilic layer. In one embodiment of the methods, the hydrophilic layer is characterized by the absence of removal of the hydrophilic layer in the laser-exposed areas during steps (b) and (c). In a preferred embodiment, the absorption of infrared radiation in the laser-exposed areas of the surface layer of step (b) is sufficient to cause the surface layer in the laser-exposed areas to become removable by cleaning with water or the cleaning solution but insufficient to remove by ablation greater than 5% by weight, more preferably greater than 2% by weight, and most preferably none, of the surface layer in the laser-exposed areas. Thus, the methods of this invention provide a wet lithographic printing member with a very low or zero level of emission of gases and airborne debris during laser imaging, while also achieving excellent cleanability of the laser-exposed areas by water or an equivalent environmentally-acceptable aqueous solution and excellent image resolution and durability due to the properties of the infrared-absorbing and hydrophilic layers and their interface, as described herein.
Another aspect of the methods of imaging a wet lithographic printing member of this invention pertains to the inclusion of a primer layer interposed between the hydrophilic layer and the infrared-absorbing layer to further enhance the desirable properties of the infrared-absorbing and hydrophilic layers and their interface which greatly influence the amount of airborne materials produced during laser imaging, the speed of laser imaging, the ease of cleanability by water during removal of the laser-exposed areas, and the image resolution and durability, as described herein. In one embodiment of the methods, a primer layer is interposed between the hydrophilic layer and the surface layer in step (a) of the methods of this invention described hereinabove, which primer layer comprises an adhesion-promoting agent. In one embodiment, the thickness of the primer layer of step (a) is from 0.01 to 0.1 microns. In one embodiment, the adhesion-promoting agent of the primer layer comprises a crosslinked, polymeric reaction product of a hydrophilic polymer and a crosslinking agent, and preferably, further comprises a catalyst. In one embodiment, the primer layer comprises an organic sulfonic acid component. In one embodiment, the primer layer comprises a zirconium compound.
The term xe2x80x9cprinting member,xe2x80x9d as used herein, is synonymous with the term xe2x80x9cplatexe2x80x9d and pertains to any type of printing member or surface capable of recording an image defined by regions exhibiting differential affinities for ink and/or fountain solution. The term xe2x80x9ccleaning solution,xe2x80x9d as used herein, pertains to a solution used to clean or remove the coating or coatings from the laser-exposed regions of the print members of the methods of this invention and may be water, combinations of at least 90% water and 10% or less organic solvents and additives such as alcohols, surfactants, and glycols, and buffered or salt-containing neutral or nearly neutral water solutions, such as known in the art of aqueous fountain solutions for wet lithographic printing. The term xe2x80x9ccleaning solution,xe2x80x9d as used herein, does not include alkaline aqueous solutions with a pH of greater than about 10, acidic aqueous solutions with a pH of less than about 3.5, or organic solvents without at least 90% by weight of water present. In a preferred embodiment, the surface layer in the areas not exposed by the laser is further characterized by being not removable by cleaning with water or a cleaning solution and by durability on a wet lithographic printing press.
In one embodiment, the weight of the infrared-absorbing layer of the printing members of the methods of this invention is from about 0.05 to about 1.0 g/m2. In a preferred embodiment, the weight of the infrared-absorbing layer is from about 0.1 to about 0.5/m2.
In one embodiment of the methods of this invention, the infrared-absorbing layer, which is the surface layer in a two layer plate construction of a hydrophilic layer and an infrared-absorbing layer on a substrate, comprises one or more polymers and an infrared-absorbing sensitizer. In one embodiment, the infrared-absorbing sensitizer is a carbon black. In one embodiment, the infrared-absorbing layer comprises one or more carbon blacks selected from the group consisting of: sulfonated carbon blacks having sulfonated groups on the surface of the carbon black, carboxylated carbon blacks having carboxyl groups on the surface of the carbon black, and carbon blacks having a surface active hydrogen content of not less than 1.5 mmol/g. In a preferred embodiment, the infrared-absorbing sensitizer is CAB-O-JET 200. In another preferred embodiment, the infrared-absorbing sensitizer is BONJET BLACK CW-1. In one embodiment, the infrared-absorbing sensitizer is present in an amount greater than 55% by weight of the infrared-absorbing layer. In one embodiment, the infrared-absorbing sensitizer is present in an amount greater than 65% by weight of the infrared-absorbing layer.
In one embodiment of the methods of this invention, one of the one or more polymers of the infrared-absorbing layer comprises a polymer selected from the group consisting of: polyvinyl alcohols, polyurethanes, epoxy polymers, vinyl polymers, acrylic polymers, and cellulosics. In one embodiment, the infrared-absorbing layer comprises a polyvinyl alcohol. In one embodiment, the polyvinyl alcohol is present in an amount of 20 to 95 per cent by weight of the total weight of polymers present in the infrared-absorbing layer. As used herein, for the purposes of determining the weight per cent of a material, the term xe2x80x9cpolymersxe2x80x9d includes all the materials which are polymeric film formers, including monomeric species which polymerize or combine with a polymeric species, such as, for example, a monomeric crosslinking agent. In one embodiment, the polyvinyl alcohol is present in an amount of 25 to 75 per cent by weight of the total weight of polymers present in the infrared-absorbing layer. Suitable polymers for use in combination with polyvinyl alcohol in the infrared-absorbing layer include, but are not limited to other water-soluble or water-dispersible polymers such as, for example, polyurethanes, cellulosics, epoxy polymers, acrylic polymers, and vinyl polymers.
In one embodiment of the methods of the present invention, the infrared-absorbing layer comprises a crosslinking agent, preferably a melamine. In one embodiment, one or more polymers of the infrared-absorbing layer comprise a crosslinked, polymeric reaction product of a polymer and a crosslinking agent. In a preferred embodiment, the crosslinked, polymeric reaction product is selected from the group consisting of crosslinked reaction products of a crosslinking agent with the following polymers: a polyvinyl alcohol; a polyvinyl alcohol and a vinyl polymer; a cellulosic polymer; a polyurethane; an epoxy polymer; an acrylic polymer; and a vinyl polymer.
In one embodiment of the methods of the present invention, the infrared-absorbing layer further comprises a catalyst in addition to one or more polymers and an infrared-absorbing sensitizer.
In one embodiment of the methods of this invention, the infrared-absorbing layer comprises one or more polymers, an infrared-absorbing sensitizer, and an organic sulfonic acid component, preferably a component of an amine-blocked p-toluenesulfonic acid. In one embodiment, the organic sulfonic acid component is present in an amount of 25 to 75 weight per cent of the total weight of polymers present in the infrared-absorbing layer of the printing members of the methods of the present invention. In another embodiment, the organic sulfonic acid component is present in an amount of 35 to 55 weight per cent of the total weight of polymers present in the infrared-absorbing layer. In one embodiment, the infrared-absorbing layer comprises greater than 5% by weight of the organic sulfonic acid component. In one embodiment, the infrared-absorbing layer comprises greater than 12% by weight of the organic sulfonic acid component.
In one embodiment of the methods of preparing a wet lithographic printing member of the present invention, the hydrophilic layer comprises a crosslinked, polymeric reaction product of a hydrophilic polymer and a first crosslinking agent. Suitable hydrophilic polymers for the crosslinked, polymeric reaction product include, but are not limited to, polyvinyl alcohols and cellulosics. In a preferred embodiment, the hydrophilic polymer is a polyvinyl alcohol. In one embodiment, the first crosslinking agent is a zirconium compound. In one embodiment, the first crosslinking agent is ammonium zirconyl carbonate. In a preferred embodiment, the first crosslinking agent is ammonium zirconyl carbonate, and the ammonium zirconyl carbonate is present in an amount greater than 10% by weight of the polyvinyl alcohol, and, more preferably, present in an amount of 20 to 50% by weight of the polyvinyl alcohol. In another preferred embodiment, the hydrophilic layer further comprises a second crosslinking agent. In one embodiment, the hydrophilic layer further comprises a crosslinked, polymeric reaction product of a polyvinyl alcohol and the second crosslinking agent. In one embodiment, the second crosslinking agent is a melamine. In one embodiment, the hydrophilic layer further comprises a catalyst for the second crosslinking agent. In one embodiment, the catalyst is an organic sulfonic acid component. In one embodiment, the hydrophilic layer comprises an inorganic xerogel layer, which xerogel layer preferably comprises a zirconium oxide xerogel.
In one embodiment of the printing members of the methods of the present invention, the thickness of the hydrophilic layer is from about 1 to about 40 microns. In one embodiment, the thickness of the hydrophilic layer is from about 2 to about 25 microns.
In one embodiment of the printing members of the methods of preparing a wet lithographic printing plate member of this invention, suitable substrates comprise non-metal substrates and non-hydrophilic substrates, preferably papers, polymeric films, and non-hydrophilic metals such as non-hydrophilic aluminum. In one embodiment, the substrate is selected from the group of polymeric films consisting of: polyesters, polycarbonates, and polystyrene. In one embodiment, the polyester polymeric film is a polyethylene terephthalate film. In one embodiment, the non-hydrophilic metal substrate comprises a non-hydrophilic polymer layer on at least one surface of the non-hydrophilic metal substrate. In one embodiment, the substrate is a hydrophilic metal. Suitable metals for the hydrophilic metal substrate include, but are not limited to, aluminum, copper, steel, and chromium. In a preferred embodiment, the metal substrate is grained, anodized, silicated, or a combination thereof. In one embodiment, the metal substrate is aluminum. In a preferred embodiment, the metal substrate is an aluminum substrate comprising a surface of uniform, non-directional roughness and microscopic depressions, which surface is in contact to the hydrophilic layer and, more preferably, this surface of the aluminum substrate has a peak count in the range of 300 to 450 peaks per linear inch which extend above and below a total bandwidth of 20 microinches.
Another aspect of the present invention pertains to methods of preparing a wet lithographic printing member, which methods comprise the steps of (a) coating onto a substrate a liquid mixture comprising a first liquid medium, a hydrophilic polymer, and a first crosslinking agent; (b) drying the layer formed in step (a) to remove the first liquid medium, to cause a portion of the first crosslinking agent present to react, and to form a hydrophilic layer; (c) coating onto the hydrophilic layer a liquid mixture comprising a second liquid medium, a polymer, an infrared-absorbing sensitizer, and a second crosslinking agent; (d) drying the layer formed in step (c) to remove the second liquid medium, to cause an additional portion of the first crosslinking agent present in the hydrophilic layer to react, to cause a portion of the second crosslinking agent present to react, and to form an ink-accepting and infrared-absorbing surface layer; thereby forming a positive working lithographic printing member, wherein the surface layer and the hydrophilic layer are characterized by being not removable by cleaning with water or a cleaning solution; (e) exposing the positive working member of step (d) to absorbable infrared radiation using an infrared-emitting laser to effect absorption of infrared radiation in the laser-exposed areas of the surface layer that is sufficient to cause the surface layer in the laser-exposed areas to become removable by cleaning with water or the cleaning solution but insufficient to remove by ablation greater than 10% by weight of the surface layer in the laser-exposed areas; and (f) removing, with water or the cleaning solution, the laser-exposed areas of the surface layer to reveal the underlying hydrophilic layer. In one embodiment of the methods, subsequent to step (b) and prior to step (c), there are two steps of (i) coating onto the hydrophilic layer a liquid mixture comprising a liquid medium and an adhesion-promoting agent; and (ii) drying the layer formed in step (i) to remove the liquid medium of step (i) and to form a primer layer; and step (c) then comprises coating onto the primer layer the liquid mixture comprising a second liquid medium, a polymer, an infrared-absorbing sensitizer, and a second crosslinking agent. In one embodiment of the methods, the hydrophilic layer is characterized by the absence of removal of the hydrophilic layer in the laser-exposed areas during steps (e) and (f). In a preferred embodiment, the absorption of infrared radiation in the laser-exposed areas of step (e) is sufficient to cause the surface layer in the laser-exposed areas to become removable by cleaning with water or the cleaning solution but insufficient to remove by ablation greater than 5% by weight, more preferably greater than 2% by weight, and most preferably none, of the surface layer in the laser-exposed areas. In one embodiment, the weight of the infrared-absorbing layer of the printing members of the methods of this invention is from about 0.05 to about 1.0 g/m2. In a preferred embodiment, the weight of the infrared-absorbing layer is from about 0.1 to about 0.5 g/m2.
Another aspect of the present invention pertains to methods of preparing a wet lithographic printing member, which methods comprise the steps of: (a) coating onto a substrate a liquid mixture comprising a first liquid medium, a hydrophilic polymer, and a first crosslinking agent; (b) drying the layer formed in step (a) to remove the first liquid medium and to form a hydrophilic layer; (c) coating onto the hydrophilic layer a liquid mixture comprising a second liquid medium, a polymer, an infrared-absorbing sensitizer, and a second crosslinking agent; wherein a portion of the second crosslinking agent penetrates into the hydrophilic layer; (d) drying the layer formed in step (c) and the underlying hydrophilic layer to remove the second liquid medium, to cause a portion of the second crosslinking agent present in the hydrophilic layer to react, and to form an ink-accepting and infrared-absorbing surface layer; thereby forming a positive working lithographic printing member, wherein the surface layer and the hydrophilic layer are characterized by being not removable by cleaning with water or a cleaning solution; (e) exposing the positive working member of step (d) to absorbable infrared radiation using an infrared-emitting laser to effect absorption of infrared radiation in the laser-exposed areas of the surface layer that is sufficient to cause the surface layer in the laser-exposed areas to become removable by cleaning with water or the cleaning solution but insufficient to remove by ablation greater than 10% by weight of the surface layer in the laser-exposed areas; and (f) removing, with water or the cleaning solution, the laser-exposed areas of the surface layer to reveal the underlying hydrophilic layer. In one embodiment of the methods, subsequent to step (b) and prior to step (c), there are two steps of (i) coating onto the hydrophilic layer a liquid mixture comprising a liquid medium and an adhesion-promoting agent; and (ii) drying the layer formed in step (i) to remove the liquid medium of step (i) and to form a primer layer; and step (c) then comprises coating onto the primer layer the liquid mixture comprising a second liquid medium, a polymer, an infrared-absorbing sensitizer, and a second crosslinking agent. In one embodiment of the methods, the hydrophilic layer is characterized by the absence of removal of the hydrophilic layer in the laser-exposed areas during steps (e) and (f). In a preferred embodiment, the absorption of infrared radiation in the laser-exposed areas of the surface layer of step (e) is sufficient to cause the surface layer in the laser-exposed areas to become removable by cleaning with water or the cleaning solution but insufficient to remove by ablation greater than 5% by weight, more preferably greater than 2% by weight, and most preferably none, of the surface layer in the laser-exposed areas. In one embodiment, the weight of the infrared-absorbing layer is from about 0.05 to about 1.0 g/m2. In a preferred embodiment, the weight of the infrared-absorbing layer is from about 0.1 to about 0.5 g/m2.
Still another aspect of this invention pertains to methods of preparing a wet lithographic printing member, which methods comprise the steps of: (a) coating onto a substrate a liquid mixture comprising a first liquid medium, one or more hydrophilic polymers, and a first crosslinking agent, wherein the first crosslinking agent is present in an amount greater than 10% by weight of the one or more hydrophilic polymers; (b) drying the layer formed in step (a) to remove the first liquid medium and to form a hydrophilic layer; (c) coating onto the hydrophilic layer a liquid mixture comprising a second liquid medium, a polymer, an infrared-absorbing sensitizer, and a second crosslinking agent; (d) drying the layer formed in step (c) to remove the second liquid medium and to form an ink-accepting and infrared-absorbing surface layer, wherein the sensitizer is present in an amount of 25 to 80% by weight of the surface layer, and the one or more polymers are present in an amount of 10 to 60% by weight of the surface layer; thereby forming a positive working lithographic printing member, wherein the surface layer and the hydrophilic layer are characterized by being not removable by cleaning with water or a cleaning solution; (e) exposing the positive working member of step (d) to absorbable infrared radiation using an infrared-emitting laser to effect absorption of infrared radiation in the laser-exposed areas of the surface layer that is sufficient to cause the surface layer in the laser-exposed areas to become removable by cleaning with water or the cleaning solution but insufficient to remove by ablation greater than 10% by weight of the surface layer in the laser-exposed areas; and (f) removing, with water or the cleaning solution, the laser-exposed areas of the surface layer to reveal the underlying hydrophilic layer. In one embodiment of the methods, the hydrophilic layer is characterized by the absence of removal of the hydrophilic layer in the laser-exposed areas during steps (e) and (f). In a preferred embodiment, the absorption of infrared radiation in the laser-exposed areas of the surface layer of step (b) is sufficient to cause the surface layer in the laser-exposed areas to become removable by cleaning with water or the cleaning solution but insufficient to remove by ablation greater than 5% by weight, more preferably greater than 2% by weight, and most preferably none, of the surface layer in the laser-exposed areas. In one embodiment, the weight of the infrared-absorbing surface layer is from about 0.05 to about 1.0 g/m2. In one embodiment, the weight of the infrared-absorbing surface layer is from about 0.1 to about 0.5 g/m2. Suitable polymers for forming the ink-accepting and infrared-absorbing layer of steps (c) and (d) include, but are not limited to, polyvinyl alcohols, polyurethanes, epoxy polymers, vinyl polymers, acrylic polymers, and cellulosics.
Another aspect of the methods of imaging a wet lithographic printing member of the present invention pertains to the inclusion of an additional ink-accepting surface layer overlying the infrared-absorbing layer to provide a basic three layer product design of ink-accepting surface layer/infrared-absorbing layer/hydrophilic layer on the substrate. This additional ink-accepting surface layer may be useful in achieving the best overall balance of properties, such as increasing the speed of laser imaging, the ease of cleanability by water during removal of the laser-exposed areas, and particularly the image resolution and durability. In one embodiment, the method of imaging a wet lithographic printing member comprises the steps of (a) providing a positive working lithographic printing member, which positive working member comprises a substrate, a hydrophilic layer overlying the substrate, an infrared-absorbing layer overlying the hydrophilic layer, and an ink-accepting surface layer overlying the infrared-absorbing layer; the surface layer being characterized by the absence of ablation from absorption of infrared imaging radiation; the infrared-absorbing layer being characterized by absorption of imaging radiation; the surface layer and the infrared-absorbing layer being characterized by being not removable by cleaning with water or a cleaning solution prior to the absorption of infrared imaging radiation and by being adapted to form a wet lithographic printing surface as a result of an imagewise exposure to absorbable infrared radiation and subsequent removal of the exposed areas of the surface layer and the infrared-absorbing layer by cleaning with water or the cleaning solution to reveal the underlying hydrophilic layer; and the hydrophilic layer being characterized by being not removable by cleaning with water or the cleaning solution; (b) exposing the positive working member of step (a) to absorbable infrared radiation using an infrared-emitting laser to effect absorption of infrared radiation in the laser-exposed areas of the infrared-absorbing layer that is sufficient to cause the surface layer and the infrared-absorbing layer in the laser-exposed areas to become removable by cleaning with water or the cleaning solution but insufficient to remove by ablation greater than 10% by weight of the combined surface layer and infrared-absorbing layer in the laser-exposed areas; and (c) removing, with water or the cleaning solution, the laser-exposed areas of the surface layer and the infrared-absorbing layer to reveal the underlying hydrophilic layer.
Another aspect of the methods of imaging a wet lithographic printing member with a basic three layer product design of this invention pertains to the inclusion of a primer layer interposed between the hydrophilic layer and the infrared-absorbing layer to further enhance the desirable properties of the infrared-absorbing and hydrophilic layers and their interface which greatly influence the amount of airborne materials produced during laser imaging, the speed of laser imaging, the ease of cleanability by water during removal of the laser-exposed areas, and the image resolution and durability, as described herein. In one embodiment of the methods, a primer layer is interposed between the hydrophilic layer and the infrared-absorbing layer in step (a) of the methods, which primer layer comprises an adhesion-promoting agent. In one embodiment, the thickness of the primer layer of step (a) is from 0.01 to 0.1 microns. In one embodiment, the adhesion-promoting agent of the primer layer comprises a crosslinked, polymeric reaction product of a hydrophilic polymer and a crosslinking agent, and preferably, further comprises a catalyst. In one embodiment, the primer layer comprises an organic sulfonic acid component. In one embodiment, the primer layer comprises a zirconium compound.
In one embodiment of the methods of imaging a wet lithographic printing member with a three-layer product design with optional primer layer of this invention, the ink-accepting surface layer comprises a crosslinked, polymeric reaction product of a polymer and a crosslinking agent. Suitable polymers for the crosslinked, polymeric reaction product includes, but are not limited to, cellulosics, acrylic polymers, polyurethanes, and epoxy polymers. In one embodiment, the ink-accepting surface layer further comprises an organic sulfonic acid component. In one embodiment, the weight of the ink-accepting surface layer is from about 0.05 to about 0.5 g/m2. In a preferred embodiment, the weight of the ink-accepting surface layer is from about 0.1 to about 0.3 g/m2. In one embodiment of the methods, the hydrophilic layer is characterized by the absence of removal of the hydrophilic layer in the laser-exposed areas during steps (b) and (c). In a preferred embodiment, the absorption of infrared radiation in the laser-exposed areas of the infrared-absorbing layer of step (b) is sufficient to cause the ink-accepting surface layer and the infrared-absorbing layer in the laser-exposed areas to become removable by cleaning with water or the cleaning solution but insufficient to remove by ablation greater than 5% by weight, more preferably greater than 2% by weight, and most preferably none, of the combined ink-accepting surface layer and infrared-absorbing layer in the laser-exposed areas.
Another aspect of the present invention pertains to methods of preparing a wet lithographic printing member with a basic three layer product design, which methods comprise the steps of (a) coating onto a substrate a liquid mixture comprising a first liquid medium, a hydrophilic polymer, and a first crosslinking agent; (b) drying the layer formed in step (a) to remove the first liquid medium, to cause a portion of the first crosslinking agent present to react, and to form a hydrophilic layer; (c) coating onto the hydrophilic layer a liquid mixture comprising a second liquid medium, a polymer, an infrared-absorbing sensitizer, and a second crosslinking agent; (d) drying the layer formed in step (c) to remove the second liquid medium, to cause an additional portion of the first crosslinking agent present in the hydrophilic layer to react, to cause a portion of the second crosslinking agent present to react, and to form an infrared-absorbing layer; (e) coating onto the infrared-absorbing layer a liquid mixture comprising a third liquid medium and an ink-accepting polymer; (f) drying the layer formed in step (e) to remove the third liquid medium and to form an ink-accepting surface layer; thereby forming a positive working wet lithographic printing member, wherein the surface layer, the infrared-absorbing layer, and the hydrophilic layer are characterized by being not removable by cleaning with water or a cleaning solution; (g) exposing the positive working member of step (f) to absorbable infrared radiation using an infrared-emitting laser to effect absorption of infrared radiation in the laser-exposed areas of the infrared-absorbing layer that is sufficient to cause the surface layer and the infrared-absorbing layer in the laser-exposed areas to become removable by cleaning with water or the cleaning solution but insufficient to remove by ablation greater than 10% by weight of the combined surface layer and infrared-absorbing layer in the laser-exposed areas; and (h) removing, with water or the cleaning solution, the laser-exposed areas of the surface and infrared-absorbing layers to reveal the underlying hydrophilic layer. In one embodiment of the methods, subsequent to step (b) and prior to step (c), there are two steps of (i) coating onto the hydrophilic layer a liquid mixture comprising a liquid medium and an adhesion-promoting agent; and (ii) drying the layer formed in step (i) to remove the liquid medium of step (i) and to form a primer layer; and step (c) then comprises coating onto the primer layer the liquid mixture comprising a second liquid medium, a polymer, an infrared-absorbing sensitizer, and a second crosslinking agent.
Still another aspect of the methods of preparing a wet lithographic printing member having a three layer product design of this invention pertains to methods comprising the steps of (a) coating onto a substrate a liquid mixture comprising a first liquid medium, a hydrophilic polymer, and a first crosslinking agent; (b) drying the layer formed in step (a) to remove the first liquid medium and to form a hydrophilic layer; (c) coating onto the hydrophilic layer a liquid mixture comprising a second liquid medium, a polymer, an infrared-absorbing sensitizer, and a second crosslinking agent; wherein a portion of the second crosslinking agent penetrates into the hydrophilic layer; (d) drying the layer formed in step (c) and the underlying hydrophilic layer to remove the second liquid medium, to cause a portion of the second crosslinking agent present in the hydrophilic layer to react, and to form an infrared-absorbing layer; (e) coating onto the infrared-absorbing layer a liquid mixture comprising a third liquid medium and an ink-accepting polymer; (f) drying the layer formed in step (e) to remove the third liquid medium and to form an ink-accepting surface layer; thereby forming a positive working wet lithographic printing member, wherein the surface layer, the infrared-absorbing layer, and the hydrophilic layer are characterized by being not removable by cleaning with water or a cleaning solution; (g) exposing the positive working member of step (f) to absorbable infrared radiation using an infrared-emitting laser to effect absorption of infrared radiation in the laser-exposed areas of the infrared-absorbing layer that is sufficient to cause the surface and infrared-absorbing layers in the laser-exposed areas to become removable by cleaning with water or the cleaning solution but insufficient to remove by ablation greater than 10% by weight of the combined surface layer and infrared-absorbing layer in the laser-exposed areas; and (h) removing, with water or the cleaning solution, the laser-exposed areas of the surface and infrared-absorbing layers to reveal the underlying hydrophilic layer. In one embodiment of the methods, subsequent to step (b) and prior to step (c), there are two steps of (i) coating onto the hydrophilic layer a liquid mixture comprising a liquid medium and an adhesion-promoting agent; and (ii) drying the layer formed in step (i) to remove the liquid medium of step (i) and to form a primer layer; and step (c) then comprises coating onto the primer layer the liquid mixture comprising a second liquid medium, a polymer, an infrared-absorbing sensitizer, and a second crosslinking agent.
In one embodiment, the infrared-absorbing layer of the three layer designs of the printing members of the methods of the present invention is ink-accepting. In one embodiment, the infrared-absorbing layer of the three layer designs of the printing members of the methods of the present invention is further characterized by not accepting ink and by accepting water on a wet lithographic printing press.
Another aspect of this invention pertains to methods for preparing a positive working, wet lithographic printing member, for both two layer and three layer product designs with highly crosslinked layers and with various approaches for interaction of the crosslinking chemistry by interfacial reactions between adjacent infrared-absorbing and hydrophilic layers. The infrared-absorbing sensitizers in the infrared-absorbing layer for use with the highly crosslinked layers of the present invention are not limited to organic sensitizers, such as carbon blacks and organic dyes, but may include inorganic and metallic sensitizers.
Still another aspect of the present invention pertains to wet lithographic printing members prepared according to the methods of this invention.
One advantage of the present invention is that the lithographic printing member or plate may be imaged at very low laser power, which eliminates ablation of the infrared-absorbing layer and of the ink accepting surface layer, if present, thus eliminating almost all or all noxious vapors and airborne debris. Since the water-based fountain solution on the wet lithographic printing press will easily clean the laser-exposed infrared-absorbing layer, and also the ink-accepting surface layer if present, from the plate, the plate is suitable for on press imaging and direct printing. Also, in the course of a long printing run, the hydrophilic layer is not solubilized by the fountain solution, and non-hydrophilic substrates may be utilized. Further, the hydrophilic layer under the non-exposed image areas of the present invention provides excellent adhesion to the overlying ink-accepting image layer since it is nearly impossible to undercut through solubilization, particularly when the hydrophilic layer is highly crosslinked, including at its interface to the infrared-absorbing layer.
The superiority of the methods and of the lithographic printing members of the methods of the present invention over those previously known is particularly manifest in the ability to be imaged rapidly with relatively inexpensive diode lasers with large spot sizes; its low laser power imaging characteristic; its elimination of noxious vapors and airborne debris during imaging; its ease of cleaning; its excellent image resolution and printing quality; its resistance to water, which provides excellent durability and image adhesion on the printing press; and its low cost of manufacture.
As one of skill in the art will appreciate, features of one embodiment and aspect of the invention are applicable to other embodiments and aspects of the invention The above-discussed and other features and advantages of the present invention will be appreciated and understood by those skilled in the art from the following detailed description and drawings.

Infrared laser-imageable lithographic printing members and methods of preparing and imaging such printing members


A suture bridge includes an elongated rigid insert including a first material, and a deformable shell including a second material, the second material being different than the first material, the shell at least partially surrounding the rigid insert, the insert and the shell collectively forming a bridge body having a first leg including a first patient contacting surface configured to contact a patient's skin, a second leg spaced from the first leg and including a second patient contacting surface configured to contact the patient's skin, a first support connected to the first leg, a second support connected to the second leg, and a traversing member extending between the first support and the second support, the traversing member being connected to the first support distal the first leg and connected to the second support distal the second leg.

Sutures are stitches used to close open wounds and/or surgical incisions of a patient. A medical practitioner generally uses a needle with an attached thread to substantially sew two adjacent sections of skin together to close the wound or incision. Surgical knots are often used to secure the sutures and ensure proper healing.
Effective surgical knots may be difficult to tie, thereby potentially allowing reopening of the wound or incision. In such cases, the patient may be at risk of infection if the wound or incision reopens. In another example, sutures and surgical knots contacting the skin can be inflammatory and/or become "ingrown" and actually impede healing of the wound or incision.
Additionally, complications may arise if the suture is tied too tightly or too loosely.
For example, wound eversion may be a desired outcome of suture technique, especially in high-tension areas of the skin, such where skin overlies the shoulder, knee, angle of the mandible, etc. Wound eversion occurs when the two wound surfaces are horizontally opposed into one another such that the closed incision is under no tension and topographically lies in a plane above the resting horizontal skin plane. Wound closures with maximal eversion resist excessive widening of the scar due to ongoing ambient stresses in the high-tension area during the wound healing and scar maturation processes. However, wound eversion can be technically difficult to achieve for less skilled operator, and a device to facilitate this is desirable. Further, there may be excessive tension on closures where an excisional defect is present in the skin. When suture is placed under excessive tension to close such wounds, the suture itself can slice through the skin ("cheesewiring"). In this setting, a surgical device interposed between the skin and suture for the purpose of spreading the suture's force over a broader area is desirable. The embodiments in the following descriptions integrate these two important functions into a single device, that is the achievement of maximal wound eversion closure with prevention of suture-induced trauma to the skin. Thus, there exists a need for suture devices that improve upon and advance the design of known suture devices.

Deformable suture bridge having an insert and methods of manufacturing and using same


The invention provides a particle-optical device for irradiating an object with a beam of particles. The device comprises a housing in which are located positioning means 1 for positioning the object within the housing. The positioning means comprise a reference body 2 supported against a supporting portion of the housing and a kinematic system—which can be manipulated—with an object carrier 9 for manipulating the object held in the object carrier in at least one degree of freedom with respect to the reference body 2, the device further comprising control means and at least one combination 23,30 of a piezo-electric position actuator 25 and a piezo-electric force sensor 35, which actuator and sensor are positioned in series, whereby the control means—in dependence upon at least one input signal from at least one sensor—generates a control signal for at least that actuator associated with said sensor, characterized in that the series-positioned actuators and sensors of said at least one combination are positioned between the housing and the reference body, the support of the reference body against the supporting portion of the housing occurring via said at least one combination.

A combination of a piezo-electric position actuator and a piezo-electric force sensor, which actuator and sensor are positioned in series, is known from the technical literature, and is often referred to using the term. "Smart Disc". In every Smart Disc, there is a control system that receives an output signal from the force sensor—in the form of a voltage signal—as an input signal for the control system and, in reaction hereto, generates a control signal for the attendant actuator. The operation of the actuator can thus be aimed at opposing the force observed by the sensor, e.g. as caused by accelerative forces associated with small vibrations, which phenomenon can be usefully exploited in opposing small vibrations. The relationship existing between the control signal generated by the control unit and the input signal received by the control unit is also referred to using the term "controller transfer", with a certain frequency-dependent characteristic and a certain amplification factor (also referred to using the term "gain").
A particle-optical device according to the opening paragraph is known from European patent application EP 1225482 A1. Said document describes a lithographic device that uses a beam of UV, electrons or ions to process a wafer for integrated semiconductor circuits. To this end, use is made of an optical system with a lens for generating and focusing a beam of particles onto a desired position on a wafer. The optics—or more specifically their lens—are supported on a horizontal main plate via three lens supports. Each of the lens supports comprises a pair of Smart Discs. The main plate can be regarded as being connected to the fixed world via air springs and dampers with a typical eigenfrequency of the order of 1 Hz. Underneath the lens is located a wafer that is supported by a wafer table, which can manipulate the wafer in the horizontal plane and also in the vertical direction, with the purpose of following vibrations in the main plate caused by the resilience of said air springs and dampers. To this end, one or more interferometers are provided, comprising part of a control circuit that ensures that the vertical distance between the main plate and the wafer remains constant, so as to achieve a correct focus.
The lens typically has a first eigenfrequency located in the range 50–150 Hz. Resonance of the lens can therefore arise as a result of environmental acoustic noise or floor vibrations, e.g. generated by apparatus surrounding the device. Such vibrations can ultimately lead to a situation whereby the accuracy of the (horizontal) positioning of the beam of particles and/or the focusing of the beam of particles on the wafer is no longer adequate. By employing the Smart Discs (of which there is a total of six, corresponding to the six degrees of freedom of the lens), the vibrations resulting from this resonance are actively damped, as a result of which an improved accuracy of the focusing of the beam of particles on the wafer can be realized.

Particle-optical device for irradiating an object


It is an object of the present technology to provide an image sensor capable of reducing crosstalk in an AD conversion unit. The image sensor includes: capacitors in an even-numbered column region; and a capacitor in an odd-numbered column region disposed facing the capacitors in the even-numbered column region with different areas.

Conventionally, there has been known a solid-state imaging device that includes a pixel unit including a plurality of pixels arranged in a matrix (see, for example, Patent Literature 1). The solid-state imaging device includes an AD conversion unit for AD (analog-to-digital)-converting an analog pixel signal based on an electrical signal that has been photoelectrically converted by a photoelectric conversion element provided in the plurality of pixels. An image is displayed on a display device or the like on the basis of the digital pixel signal AD-converted by the AD conversion unit.

Sony Semiconductor Solutions Corporation


Techniques are disclosed for troubleshooting an IP telecommunications network. A network server sends a notification message to a plurality of IP addresses each associated with a customer endpoint. The server receives a notification response from each of the customer endpoint IP addresses and determines a response time for each of the customer endpoint IP addresses. The response times are compared to an expected notification response time and those that exceeded an expected response time are geo-located. Traceroutes are performed to customer endpoint IP addresses in the same geo-located area that exceeded the expected response time. All hops between the server and the customer endpoint IP addresses for each traceroute performed are geo-coded to determine impacted and non-impacted routes between the server and each customer endpoint IP address. IP traffic between the server and a customer endpoint IP address may then be re-routed from an impacted route to a non-impacted route.

VoIP telephony service providers are entities that provide VoIP telecommunications services to their customers. To achieve this goal the service providers manage large VoIP telephony networks that utilize the Internet as the fundamental infrastructure to exchange voice data between endpoints. While the Internet may be the conduit for carrying voice traffic, a series of routers, switches, telephony servers, databases, communication devices, and other components are needed to actually manage and move the voice traffic, in the form of IP data packets, through the vast network plumbing that is the Internet.
Traditional telephony used to be solely circuit-switched and was managed by a relatively small number of service providers known as incumbent local exchange carriers (ILECs) like AT&T and Verizon. Circuit switched telephony operated (and still operates) over what is commonly known as the public switched telephone network (PSTN). The PSTN is organized as a series of switches and gateways that connect one endpoint to another over a single predetermined dedicated path. That is, there is a dedicated voice path from endpoint to endpoint (e.g., phone to phone) that is not shared by any other communication session (e.g., phone call) for the duration of that call. In practice, a calling phone requests and receives a dedicated circuit connection to the called phone, and if the called phone answers that direct circuit path remains dedicated to those endpoints for the duration of the call.
VoIP telephony systems differ from the legacy circuit-switched telephony systems. VoIP telephony does not rely on a dedicated path or circuit between endpoints. Rather, the end user device digitizes analog audio and forms it into an IP packet stream. The IP packet stream is then addressed to a destination device and routed much the same as other Internet traffic—that is it may share a "connection" and mingle with other IP data as it gets routed to its destination. When it reaches its destination, a device on the other end can re-assemble the original IP packet stream and convert it to analog audio.
Moreover, there are inter-connection points in VoIP telephony networks that allow VoIP calls and circuit-switched calls to connect with one another such that a VoIP end user can make and receive calls with a circuit-switched end user despite the network differences. It should also be noted that traditional cellular telephony is a form of circuit-switched calling that uses a cellular standard wireless interface (typically GSM or CDMA) capable of connecting with the PSTN. More recently, there are cellular wireless interfaces that utilize IP based standards (e.g. LTE or VoLTE) to wirelessly place and receive what are, in effect, VoIP calls since the newer cellular wireless interfaces are IP based rather than circuit-switched. The end result is a vast telecommunications network that provides wireline and wireless inter-connectivity for both circuit-switched devices and VoIP devices.
VoIP traffic can traverse a variety of routers and gateways, in multiple IP networks, between its source and its destination. The VoIP telephony service providers are generally responsible for maintaining a working network to ensure that calls made and received by its customers are completed. When a customer experiences trouble making and receiving calls, the VoIP telephony service provider must quickly discover and correct the problem. Often, there is no way to determine a problem until it is experienced by the customer and reported to the service provider.
What is needed are techniques to monitor the VoIP telephony network and anticipate or discover problems before they significantly affect the customer.

Techniques for troubleshooting IP based telecommunications networks


A truck bed cover may be deployed as a tonneau cover or as a canopy cover. The truck bed cover includes a top shell and right and left side shells. The side shells are operable to pivot and slide with respect to the top shell so that the cover may be deployed in a canopy cover configuration or collapsed into a tonneau cover configuration. When in the tonneau cover configuration, the truck bed cover may be tilted up to provide access to the inside of the truck bed or tilted down into a closed position.

Various styles of truck bed covers are available to provide environmental protection to the contents of a pickup truck bed. Some common styles include hinged tonneau covers that tilt up to open, roll-up tonneau covers, and truck bed caps that are also referred to as canopies, toppers and camper shells. Each style has its advantages and disadvantages, and some styles are better suited for certain applications.
In the past, a truck owner had to choose one type of cover to be installed, and once installed, it was a significant task to remove it and replace it with a different type of cover. Thus, truck owners have generally been limited to using only one or the other type of cover once they have made their choice.
What is needed, therefore, is a truck bed cover that may be deployed as a tonneau cover or as a canopy cover, and that may be easily converted between the two configurations.


In a capacitor having a high dielectric constant, the capacitor includes a cylindrical lower electrode, a dielectric layer and an upper electrode. A metal oxide layer is formed on inner, top and outer surfaces of the lower electrode as the dielectric layer. A first sub-electrode is formed on a surface of the dielectric layer along the profile of the lower electrode and a second sub-electrode is continuously formed on the first sub-electrode corresponding to the top surface of the lower electrode, so an opening portion of the lower electrode is covered with the second sub-electrode. The first and second sub-electrodes include first and second metal nitride layers in which first and second stresses are applied, respectively. Directions of the first and second stresses are opposite to each other. Accordingly, cracking is minimized in the upper electrode with the high dielectric constant, thereby reducing current leakage.

1. Technical Field
This disclosure relates to a capacitor and a method of forming the same, and more particularly, to a capacitor having a dielectric layer that includes a material of high dielectric constant and a method of forming the same.
2. Description of the Related Art
As the memory cell area of a semiconductor device decreases, the capacitance of a capacitor in the cell decreases as well. A decreased data storage capacity of the memory cell results from the reduced capacitance. Accordingly, a refresh characteristic of the memory cell deteriorates and may require a high operation voltage.
For the above reasons, ways of improving the capacitance of a memory cell without decreasing a surface of the cell area of the semiconductor device have been explored. For example, increasing the effective surface area of the capacitor and/or the dielectric constant of the dielectric layer has been suggested as ways to improve the capacitance of the capacitor.
To increase the effective surface of a capacitor, a dielectric layer of a capacitor is formed as a thin layer because the cell area of a memory device is limited and defined, or a lower electrode of a capacitor may be formed as a vertical structure, for example, in a cylindrical shape. However, the thin dielectric layer may cause an increased current leakage from the capacitor, and the vertical structure of the lower electrode increases the manufacturing costs and reduces manufacturing efficiency due to various additional complicated processes that are required to produce the vertical structure.
Recently, dielectric layers of a capacitor have included a material having a dielectric constant (k) that is greater than that of silicon oxide (hereinafter referred to as a high-k material) in order to overcome the problems associated with increasing the effective surface of a capacitor. Examples of high-k materials include metal oxides such as aluminum oxide (Al2O3), tantalum oxide (Ta2O5), and hafnium oxide (HfO2).
The use of metal oxides as high-k materials is problematic because gases around the metal oxide easily react with the metal oxide when a heat budget is applied in a subsequent process, which rapidly decreases the dielectric constant. For this reason, a polysilicon layer that is used as an upper electrode of the capacitor cannot be formed directly on the metal oxide layer because the polysilicon layer is typically formed at a temperature greater than about 700° C.
To reduce this problem, a titanium nitride layer is typically formed on the metal oxide layer before the polysilicon layer is formed, thereby preventing a chemical reaction between the polysilicon layer and the underlying metal oxide layer. However, the process of forming the titanium nitride layer on the metal oxide layer may cause additional problems.
For example, when a titanium nitride layer is formed on a dielectric layer composed of a high-k material such as hafnium oxide, gases such as titanium chloride (TiCl4) gas and ammonia (NH3) gas are generally used as the processing gases. A diffusion rate for the titanium chloride gas is greater than that of the ammonia gas, so the titanium chloride gas remains on a bottom portion of a cylindrical capacitor. The titanium chloride gas reacts with the hafnium oxide at the bottom portion of the cylindrical capacitor, thereby producing hafnium chloride (HfCl4) on the bottom portion of the capacitor. The boiling point of the hafnium chloride is very low and it easily evaporates during the formation process for the capacitor, so a thickness of the hafnium oxide layer will be locally reduced. A thin dielectric layer causes a discharge of electrons stored in the capacitor, so that data stored in a cell is unfortunately erased.
Furthermore, the surface of the titanium nitride layer has a tendency to form cracks because the internal stress of the titanium nitride layer is very high due to deposition characteristics. In particular, when a lower electrode is formed as a hemispherical grained layer or a mesh-shaped supporting pattern, the cracking is more easily generated on the titanium nitride layer because the lower electrode has a wavy surface. Decreasing a thickness of the titanium nitride layer may prevent the generation of the cracking. However, when the thickness of the titanium nitride layer is too small, for example, below about 100 Å, the titanium nitride layer no longer functions as an effective barrier metal layer. The cracking of the titanium nitride layer causes current leakage, thereby degrading the operational characteristics of the capacitor.
Embodiments of the invention address these and other disadvantages of the conventional art.

Capacitor for a semiconductor device and method of forming the same


Methods, circuits, and apparatus are provided an FPGA user, ASIC designer, or the like the ability to program a unique ID per each circuit into a memory, such as a non-volatile one-time programmable memory bank on an FPGA. This unique ID is secure such that no one else can replicate it on another part, thus keeping it unique to the user for which it was intended. An encryption engine receives plaintext and produces the unique ID that is stored in memory that is designed to only be writeable through the encryption engine. Thus, the FPGA/ASIC designer can track who is the customer they sold this part to or who the last authorized user is.

The present invention relates generally to configuring programmable logic devices, such as field programmable gate arrays, and more particularly to allowing a developer to program a unique ID onto the programmable logic device.
Field programmable gate array devices are logic or mixed signal devices that may be configured to provide a user-defined function. Modern FPGAs contain hundreds of thousands of logic gates, as well as processors, memories, dedicated analog function blocks, and other circuits. Thus, these FPGAs can be a valuable commodity that a manufacturer, distributor or the like may want to track. The tracking may be for the purpose of internal supply chain management, but it may also be for more intensive tracking after it has left the hands of the manufacturer.
For example, a developer, vendor, systems integrator or the like, who utilizes and/or programs a circuit, may not want the FPGA to be used in a competitor's device or sold to a competitor. If this does happen, the vendor may want to find out who the FPGA was originally sold as this original buyer may be in violation of certain contractual or other obligations.
Integrated circuits with some identifying ID, such as an radio frequency ID, are available. This ID may be stored in a user-programmable non-volatile one-time-programmable memory. This allows FPGA user to program their own ID on to the part. However, there is no mechanism which prevents someone else from repeating that same Serial ID on another part or circuit. Thus, this circuit cannot be adequately traced. A unique ID could be installed by a manufacturer, but this could be problematic, for example, when the end user (vendor) needs to program their own unique ID.
Therefore, it is desirable to provided circuits, apparatus, and methods for providing a unique unit ID tag that cannot be easily replicated to another device.


An image processing apparatus has an extraction unit, a base calculation unit, a recommended-region calculation unit and a display unit. The extraction unit extracts a region including a branch artery of a subject based on volume data. The base calculation unit calculates a base of the branch artery based on the region including the branch artery. The recommended-region calculation unit calculates a recommended region for placing a balloon of a balloon catheter based on the volume data and the base. The display unit aligns and displays the recommended region on a basic image.

Conventionally, in the industrial field such as non-destructive inspections and the medical field such as medical examinations, an X-ray radiographic apparatus is used widely, where the X-ray radiographic apparatus irradiates a test object or a subject with radiation (typically X-rays), detects an intensity distribution of the radiation transmitted through the test object or the subject, and thereby obtains an image of the test object or the subject.
Intra-aortic balloon pumping (IABP) is used under conditions of decreased cardiac output and lowered blood pressure resulting from a significant decline in cardiac function. Application of IABP to various cases including valve replacement procedures, coronary artery disease surgeries, severe angina, and reconstructive coronary artery surgeries has been reported recently. The IABP is a simple and safe technique, and is thus expected to be applied to a wide range of cases in future.
If an IABP balloon catheter is inserted in the aorta of a patient and the balloon is inflated and deflated in synchronization with the heartbeat, IABP is effective in increasing myocardial oxygen supply and decreasing myocardial oxygen consumption. When IABP is used, the balloon assists the heart, reducing the load on the heart, and thereby making it possible to maintain blood flow through the coronary arteries and blood circulation through the whole body. The IABP, if performed until the cardiac function is restored, can reduce the possibility of the patient falling into a serious condition.
According to conventional techniques, a recommended placement position of the balloon of the IABP balloon catheter is a position 1 to 2 cm away from a base of the left subclavian artery (LSCA) in a direction of the feet. However, LSCA position serving as a reference for the placement position of the balloon is not clearly visible on X-ray images.
In actual clinical situations, a method is adopted which indirectly places the balloon of the IABP balloon catheter at a recommended position with reference to another landmark (the carina, aortic knob, or the like) visible on X-ray images. However, depending on the patient, the balloon is brought into contact with or too close to the LSCA, failing to provide an intended effect.

Image processing apparatus, X-ray radiographic apparatus, and image processing method


Disclosed is a lighting apparatus for reducing total harmonic distortion (THD). The lighting apparatus may include a lighting unit having a plurality of LED groups divided into first and second lighting groups, and the lighting unit may provide a current path for light emission corresponding to a change of a rectified voltage, using two or more drives having the same structure.

1. Technical Field
The present disclosure relates to a lighting apparatus using an LED, and more particularly, to a lighting apparatus capable of reducing total harmonic distortion (THD).
2. Related Art
A lighting apparatus is designed to use a light source which exhibits high light emission efficiency using a small amount of energy, in order to reduce energy consumption. Representative examples of a light source used in the lighting apparatus may include an LED.
The LED is differentiated from other light sources in terms of various aspects such as energy consumption, lifetime, and light quality. However, since the LED is driven by a current, a lighting apparatus using the LED as a light source requires a large number of additional circuits for driving a current.
In order to solve the above-described problem, an AC direct-type lighting apparatus has been developed. The lighting apparatus is configured to convert an AC voltage into a rectified voltage, and drive a current using the rectified voltage such the LED emits light. The rectified voltage indicates a voltage obtained by full-wave rectifying an AC voltage. Since the lighting apparatus directly uses a rectified voltage without using an inductor and a capacitor, the lighting apparatus has a satisfactory power factor.
The lighting apparatus using an LED includes a driver which provides a current path in response to light emission following a change of the rectified voltage, and performs current regulation. The driver may be implemented with one chip including transistors such as FETs for providing a current path and performing current regulation.
The driver of the lighting apparatus using an LED emits light in response to a change of the rectified voltage, and nonlinearly controls a current for light emission.
However, the lighting apparatus using an LED has a problem that THD is high due to the nonlinear change of the current. Therefore, the lighting apparatus using an LED needs to improve power efficiency by reducing the THD.


One or more light sources, one or more detectors, a processor, and a controller are configured to provide spot illumination that follows a moving object, a moving occupant, or a portion of a moving occupant in the vehicle.

Interior lighting in a vehicle may be used to illuminate an occupant, illuminate an area, such as the lap of an occupant who may be looking at a book, map, or electronic device and/or to illuminate a surface or object of the interior of the vehicle such as a seat or floor of the vehicle, a door handle, lock, window crank, or switch for locks or windows, outline of gauges, entertainment devices, seating area, foot area, or arm rest areas.

Vehicle interior lighting and illumination


Detection method and device for a receiver in a digital communication system designed to process a frame comprising a periodic sub-set of length n, said method comprising the following steps:—determining a first vector u having a length n;—determining a second shifted vector v;—calculating a correlation function between said first and second vectors;—calculating a quadratic error function between said first and second vectors;—calculating a first cost function that is a linear combination of both preceding functions and, according to the sign of the result,—calculating a second cost function of frame beginning estimate; and—starting the communication system receiver.

In any digital communication system, and in particular in wireless communication systems, the receiver is equipped, amongst other things, with a detection mechanism and a frame start time estimation mechanism.
Detection is a well-known issue in the state of the art. It is an operation that consists in processing a signal received from a transmitter in order to determine if this signal is carrying useful information. Referring to FIG. 1, there is shown a receiver 1 receiving a signal that is also transmitted to a cost function F1 computation block 2. The result of the cost function is transmitted to a comparator 3 that compares this value with the value of a preset threshold K. The result of the comparison is then used, as represented in FIG. 2, to discriminate the signal from the noise and to activate receiver 1.
Consequently, threshold K is especially important since it directly determines the enabling of receiver 1. Moreover, the threshold affects the performance of the detector and in particular the probability of a detection error, be it false alarm (FA)—i.e. the detection of a signal whereas there is only noise—or a miss detection (absence of signal detection).
In a more formal way, let us adopt the following expression conventions:    H0: hypothetical case where there is only noise    H1: hypothetical case where both signal and noise are present    D0: hypothetical case where there is detection of noise only    D1: hypothetical case where there is detection of signal and noise
A traditionally used cost function consists in establishing a correlation between various samples of the received signal, the probability law of the cost function being different according to whether the hypothetical case H0 or H1 applies.
If one considers the characteristic curves of the probability density function of this cost function in the two possible cases (FIG. 3), the traditional method consists in setting a threshold K that will make it possible to decide between one and the other hypothesis. The probability of a detection error can then be written as follows:P[(D1,H0)∪(D0,H1)]=p(Fc>K,n)+p(Fc<K,s)
It can be shown that the intersection of both curves determines the value of an optimal threshold K that makes it possible to minimize the sum of the above terms. It is thus necessary, in the receiver, to adjust threshold K used in the mechanism of FIG. 1 in order to set its value to the optimal threshold because the threshold directly determines the performance of the detector. If a threshold is set too low the first term of the above equation will increase—i.e. the probability of false alarm—and, if the threshold is set too high, then the other term will increase, thus increasing the risk of signal miss detection. Only the optimal value, represented in FIG. 3, makes it possible to minimize the mathematical expression above thus ensuring to obtain detection with as few errors as possible.
In practice, the signal and noise probability density are not precisely known and thus the value of threshold K must be approximately set by empiric means.
As a result, the detector's performance is poor.
Moreover, It can be noted that threshold K directly affects the operation known as frame start time estimation, namely determining the exact moment when the signal becomes informative. Once the presence of a periodic signal has been detected, it is important to be able to identify the beginning of the frame. Such estimation must allow the receiver to precisely target the first symbols received from the transmitter. If threshold K is empirically set too low, then the receiver will have to manage a lot of false detections and, in the opposite case, the signal will not be detected anymore. Thus, the detection operation indeed has a direct influence on the estimation operation.
Therefore, with known techniques one is confronted with the insurmountable problem of having to precisely determine the threshold K to use in a detector. In practice, it is impossible to determine an optimal threshold because of the difficulty of knowing precisely the distribution laws and their characteristics in relation to the signal and noise in a concrete case. Then there is often no other option than to set threshold K in an empirical and approximate way, by studying the behavior of the channel.
This is the reason why, regarding detection or estimation, known receivers show limited performance whatever the particular technique employed: MC (Maximum Correlation), Minimum Mean Square Error (MMSE), SCHMIDL, for all these techniques start from the postulate that the threshold must be set to its optimal value. The problem common to all these techniques lies in the importance of appropriately setting the value of threshold K.
It would be desirable to find an alternative technique and to be freed from having to determine threshold K for carrying out detection and more generally for controlling a receiver in a digital communication system.

Method and system for controlling a receiver in a digital communication system


A seat assembly is provided for supporting an occupant above a floor in an automotive vehicle. The seat assembly includes a seat cushion that is adapted to be pivotally coupled to the floor. The seat assembly also includes a seatback that is operatively coupled to the seat cushion for movement between an upright position and a folded position overlying the seat cushion. A linkage system is operatively coupled between the seatback, seat cushion, and the floor. The linkage system automatically moves the seat cushion downward and forward and translates the seatback downward and rearward in response to movement of the seatback between the upright position and the folded position.

1. Field of the Invention
The invention relates to a seat assembly for an automotive vehicle. More particularly, the invention relates to a seat assembly having a linkage system for automatically moving a seat cushion downward and forward and translating a seatback downward and rearward in response to pivoting the seatback between an upright position and a folded position.
2. Description of Related Art
Automotive vehicles include one or more seat assemblies for supporting seat occupants within a passenger compartment of the vehicle. Typically, seat assemblies include a generally horizontal seat cushion and a generally vertical seatback. It is well known in the seating art to provide a stowable seat assembly movable between a seating position for supporting the seat occupant above the floor and a stowed position lying flat against the floor, or nested within a recess formed in the floor.
In such stowable seat assemblies, the seatback is normally pivotally coupled to the seat cushion at a seatback pivot located between a lower end of the seatback and a rearward end of the seat cushion. The seatback pivot allows the seatback to pivot between a generally upright position and a folded position overlying the seat cushion. The seat cushion often includes a four-bar-linkage or front and rear legs extending between the seat cushion and the floor of the vehicle for moving the seat cushion between a raised position spaced above the floor and a lowered position resting along the floor. The seatback defines a load floor when the seat assembly is in the stowed position.
When such stowable seat assemblies are in a second or third row, behind a forward seat, an interference condition is often created when folding the seatback forward. Specifically, the seatback cannot pivot between the upright position and the folded position without an upper end of the seatback contacting the forward seat. This interference condition is magnified by federal motor vehicle safety standards, such as FMVSS 202a, which create high seatback height requirements. In addition, with the seatback pivotally coupled to the seat cushion at the seatback pivot, the load floor height is determined by the amount the seat cushion is lowered toward the floor.
It is therefore desirable to provide a mechanism or linkage system which lowers the seatback pivot such that the seatback is at a predetermined load floor height when the seat assembly is in the stowed position. It is also desirable that the linkage system translates the seatback pivot rearward such that the upper end of the seatback clears a forward seat as the seatback moves between the upright position and the folded position. It is further desirable that this motion be done while lowering the seat cushion.

Fold flat seat assembly with rearward folding motion