Eastman-kodak Company

Kodak Polychrome Graphics, Gmbh

Kodak Graphic Communications Gmbh

Sun Chemical Corporation

Other

Harald Baumann

Udo Dwars

Bernd Strehmel

Christopher D Simpson

Hans-Joachim Timpe

Celin M Savariar-Hauck

Michael Flugel

Ulrich Fiebag

Mathias Jarek

Detlef Pietsch

Tanja Ebhardt

Domenico Balbinot

Saija Werner

Axel Draber

Gerhard Hauck

James Russell Matz

Paul A Perron

Eduard Kottmair

Hans-Horst Glatt

Maria T Sypek

Melinda A Alden

Stephan J Platzer

Oliver Piestert

Anthony Paul Kitson

Akira Igarashi

Philip John Watkiss

Robert Walter Fuss

Dietmar Frank

Uwe Tondock

Ursula Muller

Socrates Peter Pappas

Ursula Müller

Hans-Peter Herting

Friederike Von Gyldenfeldt

Ingrid Glatt

Sandrine Waig Fang

Yuuki Torihata

Daniela Lummel

Alessandro Gandini

Michael Mursal

Oliver Plestert

Ulrike Dallmann

Lithographic printing plates are provided by imagewise exposing negative-working lithographic printing plate precursors having a negative-working radiation-sensitive imageable layer, followed by contacting with a processing solution that has a pH of at least 7 and up to and including 11. This processing solution also includes component (1) that is a nitrogen-containing base having an atmospheric pressure melting point of at least 40&#xb0; C.; component (2) that is a non-ionic surfactant that independently has an atmospheric pressure melting point, glass transition temperature, or pour point of at least 40&#xb0; C.; component (3) that is a hydroxy-containing solution promoter; and component (4) that is a hydrophilic surface protective compound. The method is carried out in a manner such that the exposed and processed precursor is not further treated with any liquid (such as gumming or rinsing solution) between processing and mounting onto a printing press.

Method for making lithographic printing plates

Negative-working lithographic printing plate precursors have improved bakeability and good shelf life and can be imaged using either UV or infrared radiation. These precursors have a negative-working imageable layer that has a unique polymeric binder comprising a polymeric backbone and further comprising at least (a) and (b) pendant groups distributed in random order along the polymeric backbone. The (a) pendant groups are ethylenically unsaturated polymerizable groups, and the (b) pendant groups are defined by Structures (I), (II), and (III) described in the disclosure.

Negative-working lithographic printing plate precursor

A lithographic printing plate precursor comprises an imageable layer comprising a free radically polymerizable component, an initiator composition capable of generating free radicals upon exposure to imaging infrared radiation, an infrared radiation absorbing dye that is defined by Structure (I) shown in the disclosure, which dyes comprise one or more ethylenically unsaturated polymerizable groups in an organic group that is attached to the methine chain. These infrared radiation absorbing dyes exhibit a reduced tendency to crystallize in the imageable layers in the presence of tetraaryl borate counter anions and therefore provide improved shelf life.

Negative-working lithographic printing plate precursors with IR dyes

Negative-working lithographic printing plate precursor a negative-working imageable layer and an outermost water-soluble overcoat layer that is disposed directly on the negative-working imageable layer. The outermost water-soluble overcoat layer comprises: (1) one or more film-forming water-soluble polymeric binders, (2) organic wax particles, and (3) non-wax matte particles. The outermost water-soluble overcoat layer has a dry thickness (t) that is defined by the following equation (I):wherein w is the dry coverage of the outermost water-soluble overcoat layer in g/m, and r is 1 g/cm. The organic wax particles have an average largest dimension D(wax) that is less than 0.9 of t (in &#x3bc;m), and the non-wax matte particles have an average largest dimension D(matte) that defined by the following equation (II):1.5 times(matte)&#x2266;40 times(in &#x3bc;m).

Lithographic printing plate precursors and use

A lithographic printing plate precursor comprises an imagable layer comprising a free radically polymerizable component, an initiator composition capable of generating free radicals upon exposure to imaging infrared radiation, an infrared radiation absorbing dye comprising an infrared radiation absorbing cation and a counter anion, and a polymeric binder. The salt formed between the infrared radiation absorbing cation and a tetraphenyl borate has solubility in 2-methoxy propanol at 20&#xb0; C. that is greater than or equal to 3.5 g/l. The use of these infrared radiation absorbing dyes in the imagable layers provides a reduced tendency of these dyes to crystallize in the presence of tetraaryl borate counter anions.

Negative-working lithographic printing plate precursors

A negative-working lithographic printing plate precursor comprises a negative-working radiation-sensitive imageable layer and an outermost layer comprising a vinyl alcohol copolymer comprising at least one unit of each of the (a), (b), and (c) recurring units, in any order, defined in the disclosure. The (c) recurring units are present in the vinyl alcohol copolymer in an amount of at least 0.5 mol %, based on the total recurring units. These precursors can be used to prepare lithographic printing plates either on-press or off-press after imaging using near-UV, visible, or infrared radiation.

Negative-working lithographic printing plate precursors and use

A method is described for producing an imaged lithographic printing plate, wherein the developer comprises a hydrophilic polymer which comprises (m1) primary, secondary and/or tertiary amino groups, and (m2) acid groups selected from &#x2014;COOH, &#x2014;SOH, &#x2014;POH and &#x2014;POH, and (m3) optionally alkylene oxide units &#x2014;(CHR&#x2014;CH&#x2014;O)&#x2014;, wherein Ris H or &#x2014;CHand p is an integer from 1 to 50.

Processing of lithographic printing plates with a developer solution containing a hydrophilic polymer

Lithographic printing plate precursor comprising (a) a lithographic substrate with a hydrophilic surface and (b) a radiation-sensitive coating on the hydrophilic surface comprising (i) one or more types of monomers and/or oligomers and/or polymers, each comprising at least one ethylenically unsaturated group accessible to a free-radical polymerization, (ii) at least one sensitizer, and (iii) at least one coinitiator capable of forming free radicals together with the sensitizer, said coinitiator being other than metallocenes, characterized in that the at least one sensitizer comprises a compound of formula (I) wherein at least one of the groups Rto Ris a bulky group which has a van der Waals volume of at least 55 &#x212b;. 

UV-sensitive lithographic printing plate precursor with benzoxazole derivative and analogues thereof as sensitizer

A method is described for producing an imaged lithographic printing plate, wherein the developer comprises a hydrophilic polymer comprising (m1) structural units derived from at least one compound comprising both a polyalkylene oxide chain and a free radical polymerizable group, and (m2) structural units derived from at least one compound copolymerizable with the free radical polymerizable group of (i) and comprising at least one functional group with pK&#x3c;5.

Method for developing and sealing of lithographic printing plates

Negative-working imageable elements can be imaged and processed to provide lithographic printing plates. These imageable elements are sensitive to infrared radiation but are insensitive to 'white' light and thus can be more easily handled under white light conditions. These properties are possible by incorporating a filter dye having a &#x3bb;of from about 300 to about 500 nm into the imageable layer of the imageable elements.

Negative-working imageable elements

Method for producing an imaged lithographic printing plate comprising the step of developing an imagewise exposed negative working precursor with a developer comprising an alkylene oxide derivative of formula (A), wherein Ris a linear or branched Cto Calkyl group or H, (n+m) is an integer from 2 to 30, and RRRand Rare each independently selected from H, methyl and ethyl, with the proviso that at least one of Rand Ris not H, and with the further proviso that at least one of Rand Ris not H. 

Method for making lithographic plates

Negative-working imageable elements such as lithographic printing plate precursors, include a free-radically polymerizable component, an initiator composition that is capable of generating free radicals sufficient to initiate polymerization of the free-radically polymerizable component upon exposure to imaging radiation in the presence of a radiation absorbing compound, a radiation absorbing compound, an aerobic free radical inhibitor, optionally a polymeric binder that is not a free radically polymerizable component, and an anaerobic free radical inhibitor. The molar ratio of the anaerobic free radical inhibitor to the aerobic free radical inhibitor is at least 1:1. This combination of inhibitors provides increased shelf life and good latent image stability particularly when the element includes a polymeric topcoat layer that functions as an oxygen barrier.

Negative-working imaging elements and methods of use

Negative-working imageable element can be used to provide lithographic printing plates. The imageable element has a suitable radiation-sensitive imageable layer and a water-soluble overcoat disposed on the imageable layer. This overcoat comprises at least one poly(vinyl alcohol) having a saponification degree of at least 90%, an alkoxylation product of an alkanol, and either a 2-sulfonato succinic acid dialkylester or an alkoxylation product of a 1,4-butanediol.

Negative-working imageable elements with overcoat

Radiation-sensitive element comprising a substrate and a radiation-sensitive coating comprising (a) at least one component selected from photoinitiators and sensitizer/coinitiator systems which absorbs radiation of a wavelength in the range of 250 to 1,200 nm; (b) at least one free-radical polymerizable oligomer A having an average molecular weight in the range of 3,500 to 9,000 determined by GPC, obtainable by reacting a triisocyanate with (i) at least one acrylic or methacrylic monomer with two free OH groups and at least one (meth)acrylic group and (ii) at least one compound comprising one OH group, at least one (meth)acrylic group and at least one poly(alkyleneoxide) chain in the molecule, wherein the (meth)acrylic monomer (i) is present in an amount of 2 to 20 mole-%, based on the total amount of (meth)acrylic compounds with OH functionality.

Photopolymer composition usable for lithographic plates

Growing community of inventors

Osterode/Harz, Germany

Harald Baumann