[go: up one dir, main page]
More Web Proxy on the site http://driver.im/

EP0950518B1 - A heat mode sensitive imaging element for making positive working printing plates - Google Patents

A heat mode sensitive imaging element for making positive working printing plates Download PDF

Info

Publication number
EP0950518B1
EP0950518B1 EP19990200511 EP99200511A EP0950518B1 EP 0950518 B1 EP0950518 B1 EP 0950518B1 EP 19990200511 EP19990200511 EP 19990200511 EP 99200511 A EP99200511 A EP 99200511A EP 0950518 B1 EP0950518 B1 EP 0950518B1
Authority
EP
European Patent Office
Prior art keywords
imaging element
layer
printing plate
heat mode
making
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
EP19990200511
Other languages
German (de)
French (fr)
Other versions
EP0950518A1 (en
Inventor
Marc Van Damme
Joan Vermeersch
Guido Hauquier
Eric Verschueren
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Agfa Gevaert NV
Original Assignee
Agfa Gevaert NV
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Agfa Gevaert NV filed Critical Agfa Gevaert NV
Priority to EP19990200511 priority Critical patent/EP0950518B1/en
Publication of EP0950518A1 publication Critical patent/EP0950518A1/en
Application granted granted Critical
Publication of EP0950518B1 publication Critical patent/EP0950518B1/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Classifications

    • BPERFORMING OPERATIONS; TRANSPORTING
    • B41PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
    • B41CPROCESSES FOR THE MANUFACTURE OR REPRODUCTION OF PRINTING SURFACES
    • B41C1/00Forme preparation
    • B41C1/10Forme preparation for lithographic printing; Master sheets for transferring a lithographic image to the forme
    • B41C1/1008Forme preparation for lithographic printing; Master sheets for transferring a lithographic image to the forme by removal or destruction of lithographic material on the lithographic support, e.g. by laser or spark ablation; by the use of materials rendered soluble or insoluble by heat exposure, e.g. by heat produced from a light to heat transforming system; by on-the-press exposure or on-the-press development, e.g. by the fountain of photolithographic materials
    • B41C1/1016Forme preparation for lithographic printing; Master sheets for transferring a lithographic image to the forme by removal or destruction of lithographic material on the lithographic support, e.g. by laser or spark ablation; by the use of materials rendered soluble or insoluble by heat exposure, e.g. by heat produced from a light to heat transforming system; by on-the-press exposure or on-the-press development, e.g. by the fountain of photolithographic materials characterised by structural details, e.g. protective layers, backcoat layers or several imaging layers
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B41PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
    • B41CPROCESSES FOR THE MANUFACTURE OR REPRODUCTION OF PRINTING SURFACES
    • B41C2210/00Preparation or type or constituents of the imaging layers, in relation to lithographic printing forme preparation
    • B41C2210/02Positive working, i.e. the exposed (imaged) areas are removed
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B41PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
    • B41CPROCESSES FOR THE MANUFACTURE OR REPRODUCTION OF PRINTING SURFACES
    • B41C2210/00Preparation or type or constituents of the imaging layers, in relation to lithographic printing forme preparation
    • B41C2210/06Developable by an alkaline solution
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B41PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
    • B41CPROCESSES FOR THE MANUFACTURE OR REPRODUCTION OF PRINTING SURFACES
    • B41C2210/00Preparation or type or constituents of the imaging layers, in relation to lithographic printing forme preparation
    • B41C2210/14Multiple imaging layers
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B41PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
    • B41CPROCESSES FOR THE MANUFACTURE OR REPRODUCTION OF PRINTING SURFACES
    • B41C2210/00Preparation or type or constituents of the imaging layers, in relation to lithographic printing forme preparation
    • B41C2210/22Preparation or type or constituents of the imaging layers, in relation to lithographic printing forme preparation characterised by organic non-macromolecular additives, e.g. dyes, UV-absorbers, plasticisers
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B41PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
    • B41CPROCESSES FOR THE MANUFACTURE OR REPRODUCTION OF PRINTING SURFACES
    • B41C2210/00Preparation or type or constituents of the imaging layers, in relation to lithographic printing forme preparation
    • B41C2210/24Preparation or type or constituents of the imaging layers, in relation to lithographic printing forme preparation characterised by a macromolecular compound or binder obtained by reactions involving carbon-to-carbon unsaturated bonds, e.g. acrylics, vinyl polymers
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B41PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
    • B41CPROCESSES FOR THE MANUFACTURE OR REPRODUCTION OF PRINTING SURFACES
    • B41C2210/00Preparation or type or constituents of the imaging layers, in relation to lithographic printing forme preparation
    • B41C2210/26Preparation or type or constituents of the imaging layers, in relation to lithographic printing forme preparation characterised by a macromolecular compound or binder obtained by reactions not involving carbon-to-carbon unsaturated bonds
    • B41C2210/262Phenolic condensation polymers, e.g. novolacs, resols

Definitions

  • the present invention relates to a heat mode imaging element for preparing a lithographic printing plate. More specifically the invention is related to a heat mode imaging element for preparing a lithographic printing plate whereof the difference in the top layer of being penetrated and/or solubilised in the exposed areas and in the non-exposed areas by an aqueous developer is increased.
  • Lithography is the process of printing from specially prepared surfaces, some areas of which are capable of accepting lithographic ink, whereas other areas, when moistened with water, will not accept the ink.
  • the areas which accept ink form the printing image areas and the ink-rejecting areas form the background areas.
  • a photographic material is made imagewise receptive to oily or greasy inks in the photo-exposed (negative-working) or in the non-exposed areas (positive-working) on a hydrophilic background.
  • lithographic printing plates also called surface litho plates or planographic printing plates
  • a support that has affinity to water or obtains such affinity by chemical treatment is coated with a thin layer of a photosensitive composition.
  • Coatings for that purpose include light-sensitive polymer layers containing diazo compounds, dichromate-sensitized hydrophilic colloids and a large variety of synthetic photopolymers. Particularly diazo-sensitized systems are widely used.
  • the exposed image areas become insoluble and the unexposed areas remain soluble.
  • the plate is then developed with a suitable liquid to remove the diazonium salt or diazo resin in the unexposed areas.
  • printing plates are known that include a photosensitive coating that upon image-wise exposure is rendered soluble at the exposed areas. Subsequent development then removes the exposed areas.
  • a typical example of such photosensitive coating is a quinone-diazide based coating.
  • the above described photographic materials from which the printing plates are made are camera-exposed through a photographic film that contains the image that is to be reproduced in a lithographic printing process.
  • Such method of working is cumbersome and labor intensive.
  • the printing plates thus obtained are of superior lithographic quality.
  • GB-1 492 070 discloses a method wherein a metal layer or a layer containing carbon black is provided on a photosensitive coating. This metal layer is then ablated by means of a laser so that an image mask on the photosensitive layer is obtained. The photosensitive layer is then overall exposed by UV-light through the image mask. After removal of the image mask, the photosensitive layer is developed to obtain a printing plate.
  • This method however still has the disadvantage that the image mask has to be removed prior to development of the photosensitive layer by a cumbersome processing.
  • thermoplastic polymer particles By image-wise exposure to an infrared laser, the thermoplastic polymer particles are image-wise coagulated thereby rendering the surface of the imaging element at these areas ink-acceptant without any further development.
  • a disadvantage of this method is that the printing plate obtained is easily damaged since the non-printing areas may become ink accepting when some pressure is applied thereto. Moreover, under critical conditions, the lithographic performance of such a printing plate may be poor and accordingly such printing plate has little lithographic printing latitude.
  • US-P- 4 708 925 discloses imaging elements including a photosensitive composition comprising an alkali-soluble novolac resin and an onium-salt. This composition may optionally contain an IR-sensitizer. After image-wise exposing said imaging element to UV - visible - or IR-radiation followed by a development step with an aqueous alkali liquid there is obtained a positive or negative working printing plate. The printing results of a lithographic plate obtained by irradiating and developing said imaging element are poor.
  • EP-A- 625 728 discloses an imaging element comprising a layer which is sensitive to UV- and IR-irradiation and which may be positive or negative working. This layer comprises a resole resin, a novolac resin, a latent Bronsted acid and an IR-absorbing substance. The printing results of a lithographic plate obtained by irradiating and developing said imaging element are poor.
  • US-P- 5 340 699 is almost identical with EP-A- 625 728 but discloses the method for obtaining a negative working IR-laser recording imaging element.
  • the IR-sensitive layer comprises a resole resin, a novolac resin, a latent Bronsted acid and an IR-absorbing substance.
  • the printing results of a lithographic plate obtained by irradiating and developing said imaging element are poor.
  • GB-A- 1 208 415 discloses a method of recording information comprising information-wise heating a recording material comprising a support bearing, with or without an interlayer a heat-sensitive recording layer constituted so that such information-wise heating creates a record of the information in terms of a difference in the water permeabilities of different areas of the recording layer, treating the recording material with an aqueous liquid which penetrates through the water-permeable or more water-permeable areas of the recording layer and is constituted so as to effect a permanent physical and/or chemical change of at least the surface portions of the underlying support or inter-layer in the corresponding areas, and removing the whole of the recording layer to expose said information-wise changed support or interlayer.
  • JP-A-01-46739 discloses a method for preventing the line-like unequalities generated by foam by dissolving a photosensitive composition containing at least a photosensitive material, fluorine surfactant and defoaming agent into a coating solvent, then coating the solution on a base and drying the coating.
  • JP-A-02-29750 discloses a method for obtaining a photosensitive composition suitable for a positive photosensitive printing plate by using o-naphthoquinonediazide sulphonic acid, an alkali-soluble resin, and a non-ionic surfactant such as polyoxyethylene naphthol.
  • EP-A- 527.369 discloses a light sensitive recording material comprising a support and a positive working light sensitive layer with a rough surface, which comprises as light sensitive compound at least a 1,2-quinonediazide and as water insoluble and in water-alkaline solutions soluble or swellable binder a polycondensate or polymer and a filler, wherein the light-sensitive layer at a layer weight of 3g/m 2 or less (i) comprises as filler silica with a mean diameter from 3 to 5 ⁇ m and a final limit of 15 ⁇ m in an amount, which yields a slipperiness according to Beck from 20 till 100 seconds and (ii) furthermore comprises a surfactant with polysiloxane units.
  • EP-A- 823 327 discloses a positive photosensitive composition showing a difference in solubility in an alkali developer as between an exposed portion and a non-exposed portion, which comprises, as components inducing the difference in solubility, (a) a photo-thermal conversion material, and (b) a high molecular compound, of which the solubility in an alkali developer is changeable mainly by a change other than a chemical change.
  • EP-A- 678 380 discloses a method wherein a protective layer is provided on a grained metal support underlying a laser-ablatable surface layer. Upon image-wise exposure the surface layer is fully ablated as well as some parts of the protective layer. The printing plate is then treated with a cleaning solution to remove the residu of the protective layer and thereby exposing the hydrophilic surface layer.
  • EP-A 864 420 which is prior art under Art 54(3)EPC, discloses the use of Solsperse surfactants, availaible from ICI (later Zeneca, now Avecia Ltd.) in heat-mode lithographic printing plates.
  • a heat mode imaging element for making a lithographic printing plate having on a lithographic base with a hydrophilic surface a first layer including a polymerthat is soluble in an aqueous alkaline solution and a top layer on the same side of the lithographic base as the first layer that is IR-sensitive and unpenetrable for an alkaline developer; characterized in that at least one of said first layer and said top layer comprises a surfactant, with the proviso that the surfactant is not Solsperse 5000 or Solsperse 28000.
  • the first layer and/or the top (also called the second) layer comprises a surfactant.
  • Said surfactant can be a cationic, an anionic or an amphoteric surfactant, but is preferably a non-ionic surfactant.
  • the surfactant is preferably selected from the group consisting of perfluoroalkyl surfactants, alkylphenyl surfactants and most preferably polysiloxane surfactants. Still more preferably a combination of at least two polysiloxane surfactants is used.
  • the surfactant is preferably present in the top layer.
  • the amount of surfactant lies preferably in the range from 0.001 to 0.3g/m 2 , more preferably in the range from 0.003 to 0.050g/m 2 .
  • the top layer in accordance with the present invention comprises an IR-dye or pigment and a binder resin.
  • a mixture of IR-dyes or pigments may be used, but it is preferred to use only one IR-dye or pigment.
  • Preferably said IR-dyes are IR-cyanines dyes.
  • Particularly useful IR-cyanine dyes are cyanines dyes with two indolenine groups. Most preferably is compound I with the structure as indicated
  • Particularly useful IR-absorbing pigments are carbon black, metal carbides, borides, nitrides, carbonitrides, bronze-structured oxides and oxides structurally related to the bronze family but lacking the A component e.g. WO2.9.
  • conductive polymer dispersion such as polypyrrole or polyaniline-based conductive polymer dispersions.
  • the lithographic performance and in particular the print endurance obtained depends on the heat-sensitivity of the imaging element. In this respect it has been found that carbon black yields very good and favorable results.
  • said top layer contains an IR-dye
  • said top layer preferably also contains a dye or a pigment that absorbs in the visible region in order to be able to visually inspect the image formed after IR-radiation and development in an aqueous alkaline developer.
  • the IR-absorbing dyes or pigments are present preferably in an amount between 1 and 99 parts, more preferably between 50 and 95 parts by weight of the total amount of said IR-sensitive top layer.
  • the top layer may preferably comprise as binder a water insoluble polymer such as a cellulose ester, a copolymer of vinylidene chloride and acrylonitrile, poly(meth)acrylates, polyvinyl chloride, silicone resins, etc.
  • binder is nitrocellulose resin.
  • the total amount of the top layer preferably ranges from 0.010 to 5 g/m 2 more preferably from 0.020 to 1 g/m 2 .
  • top layer a difference in the capacity of being penetrated and/or solubilised by the aqueous alkaline solution is generated upon image-wise exposure for an alkaline developer according to the invention.
  • the said capacity is increased upon image-wise IR exposure to such degree that the imaged parts will be cleaned out during development without solubilising and/or damaging the non-imaged parts.
  • the development with the aqueous alkaline solution is preferably done within an interval of 5 to 120 seconds.
  • the present invention comprises a first layer soluble in an aqueous developing solution, more preferably an aqueous alkaline developing solution with preferentially a pH between 7.5 and 14.
  • Said layer is preferably contiguous to the top layer but other layers may be present between the top layer and the first layer.
  • the alkali soluble binders used in this layer are preferably hydrophobic binders as used in conventional positive or negative working PS-plates e.g. novolac resins, polymers containing hydroxystyrene units, carboxy substituted polymers etc.
  • hydrophobic binder used in connection with the present invention is further characterised by insolubility in water and partial solubility/swellability in an alkaline solution and/or partial solubility in water when combined with a cosolvent.
  • this aqueous alkali soluble layer is preferably a visible light- and UV-light desensitised layer. Said layer is preferably thermally hardenable.
  • This preferably visible light- and UV-desensitised layer does not comprise photosensitive ingredients such as diazo compounds, photoacids, photoinitiators, quinone diazides, sensitisers etc. which absorb in the wavelength range of 250nm to 650nm. In this way a daylight stable printing plate may be obtained.
  • Said first layer preferably also includes a low molecular acid, preferably a carboxylic acid, still more preferably a benzoic acid, most preferably 3,4,5-trimethoxybenzoic acid or a benzophenone.
  • a low molecular acid preferably a carboxylic acid, still more preferably a benzoic acid, most preferably 3,4,5-trimethoxybenzoic acid or a benzophenone.
  • the ratio between the total amount of low molecular acid or benzophenone and polymer in the first layer preferably ranges from 2:98 to 40:60, more preferably from 5:95 to 20:80.
  • the total amount of said first layer preferably ranges from 0.1 to 10 g/m 2 , more preferably from 0.3 to 2 g/m 2 .
  • the lithographic base may be an anodised aluminum.
  • a particularly preferred lithographic base is an electrochemically grained and anodised aluminum support.
  • the anodised aluminum support may be treated to improve the hydrophilic properties of its surface.
  • the aluminum support may be silicated by treating its surface with sodium silicate solution at elevated temperature, e.g. 95°C.
  • a phosphate treatment may be applied which involves treating the aluminum oxide surface with a phosphate solution that may further contain an inorganic fluoride.
  • the aluminum oxide surface may be rinsed with a citric acid or citrate solution. This treatment may be carried out at room temperature or may be carried out at a slightly elevated temperature of about 30 to 50°C.
  • a further interesting treatment involves rinsing the aluminum oxide surface with a bicarbonate solution.
  • the aluminum oxide surface may be treated with polyvinylphosphonic acid, polyvinylmethylphosphonic acid, phosphoric acid esters of polyvinyl alcohol, polyvinylsulphonic acid, polyvinylbenzenesulphonic acid, sulphuric acid esters of polyvinyl alcohol, and acetals of polyvinyl alcohols formed by reaction with a sulphonated aliphatic aldehyde It is further evident that one or more of these post treatments may be carried out alone or in combination.
  • the lithographic base having a hydrophilic surface comprises a flexible support, such as e.g. paper or plastic film, provided with a cross-linked hydrophilic layer.
  • a particularly suitable cross-linked hydrophilic layer may be obtained from a hydrophilic binder cross-linked with a cross-linking agent such as formaldehyde, glyoxal, polyisocyanate or a hydrolysed tetra-alkylorthosilicate. The latter is particularly preferred.
  • hydrophilic binder there may be used hydrophilic (co)polymers such as for example, homopolymers and copolymers of vinyl alcohol, acrylamide, methylol acrylamide, methylol methacrylamide, acrylic acid, methacrylic acid, hydroxyethyl acrylate, hydroxyethyl methacrylate or maleic anhydride/vinylmethylether copolymers.
  • the hydrophilicity of the (co)polymer or (co)polymer mixture used is preferably the same as or higher than the hydrophilicity of polyvinyl acetate hydrolyzed to at least an extent of 60 percent by weight, preferably 80 percent by weight.
  • the amount of crosslinking agent, in particular of tetraalkyl orthosilicate, is preferably at least 0.2 parts by weight per part by weight of hydrophilic binder, more preferably between 0.5 and 5 parts by weight, most preferably between 1.0 parts by weight and 3 parts by weight.
  • a cross-linked hydrophilic layer in a lithographic base used in accordance with the present embodiment preferably also contains substances that increase the mechanical strength and the porosity of the layer.
  • colloidal silica may be used.
  • the colloidal silica employed may be in the form of any commercially available water-dispersion of colloidal silica for example having an average particle size up to 40 nm, e.g. 20 nm.
  • inert particles of larger size than the colloidal silica may be added e.g. silica prepared according to Stöber as described in J. Colloid and Interface Sci., Vol.
  • alumina particles or particles having an average diameter of at least 100 nm which are particles of titanium dioxide or other heavy metal oxides.
  • the thickness of a cross-linked hydrophilic layer in a lithographic base in accordance with this embodiment may vary in the range of 0.2 to 25 ⁇ m and is preferably 1 to 10 ⁇ m.
  • plastic film e.g. substrated polyethylene terephthalate film, cellulose acetate film, polystyrene film, polycarbonate film etc.
  • the plastic film support may be opaque or transparent.
  • the amount of silica in the adhesion improving layer is between 200 mg per m 2 and 750 mg per m 2 .
  • the ratio of silica to hydrophilic binder is preferably more than 1 and the surface area of the colloidal silica is preferably at least 300 m 2 per gram, more preferably at least 500 m 2 per gram.
  • Image-wise exposure in connection with the present invention is an image-wise scanning exposure involving the use of a laser that operates in the infrared or near-infrared, i.e. wavelength range of 700-1500 nm. Most preferred are laser diodes emitting in the near-infrared. Exposure of the imaging element may be performed with lasers with a short as well as with lasers with a long pixel dwell time. Preferred are lasers with a pixel dwell time between 0.005 ⁇ s and 20 ⁇ s.
  • the heat mode imaging element is developed by rinsing it with an aqueous alkaline solution.
  • aqueous alkaline solutions used in the present invention are those that are used for developing conventional positive working presensitised printing plates, preferably containing SiO 2 in the form of silicates and having preferably a pH between 11.5 and 14.
  • the imaged parts of the top layer that were rendered more penetrable for the aqueous alkaline solution upon exposure are cleaned-out whereby a positive working printing plate is obtained.
  • the composition of the developer used is also very important.
  • the developers and replenishers for developer used in the invention are preferably aqueous solutions mainly composed of alkali metal silicates and alkali metal hydroxides represented by MOH or their oxyde, represented by M 2 O, wherein said developer comprises SiO 2 and M 2 O in a molar ratio .of 0.5 to 1.5 and a concentration of SiO 2 of 0.5 to 5% by weight.
  • alkali metal silicates preferably used are, for instance, sodium silicate, potassium silicate, lithium silicate and sodium metasilicate.
  • alkali metal hydroxides preferred are sodium hydroxide, potassium hydroxide and lithium hydroxide.
  • the developers used in the invention may simultaneously contain other alkaline agents.
  • other alkaline agents include such inorganic alkaline agents as ammonium hydroxide, sodium tertiary phosphate, sodium secondary phosphate, potassium tertiary phosphate, potassium secondary phosphate, ammonium tertiary phosphate, ammonium secondary phosphate, sodium bicarbonate, sodium carbonate, potassium carbonate and ammonium carbonate; and such organic alkaline agents as mono-, di- or triethanolamine, mono-, di- or trimethylamine, mono-, di- or triethylamine, mono- or diisopropylamine, n-butylamine, mono-, di- or triisopropanolamine, ethyleneimine, ethylenediimine and tetramethylammonium hydroxide.
  • the concentration of SiO 2 in the developer and replenisher preferably ranges from 1 to 4 % by weight. Such limitation of the concentration of SiO 2 makes it possible to stably provide lithographic printing plates having good finishing qualities even when a large amount of plates according to the invention are processed for a long time period.
  • an aqueous solution of an alkali metal silicate having a molar ratio [SiO 2 ] / [M 2 O], which ranges from 1.0 to 1.5 and a concentration of SiO 2 of 1 to 4 % by weight is used as a developer.
  • a replenisher having alkali strength equal to or more than that of the developer is employed.
  • a molar ratio, [SiO 2 ] / [M 2 O] of the replenisher is equal to or smaller than that of the developer, or that a concentration of SiO 2 is high if the molar ratio of the developer is equal to that of the replenisher.
  • organic solvents having solubility in water at 20 °C of not more than 10 by weight according to need.
  • organic solvents are such carboxilic acid esters as ethyl acetate, propyl acetate, butyl acetate, amyl acetate, benzyl acetate, ethylene glycol monobutyl acetate, butyl lactate and butyl levulinate; such ketones as ethyl butyl ketone, methyl isobutyl ketone and cyclohexanone; such alcohols as ethylene glycol monobutyl ether, ethylene glycol benzyl ether, ethylene glycol monophenyl ether, benzyl alcohol, methylphenylcarbinol, n-amyl alcohol and methylamyl alcohol; such alkyl-substituted aromatic hydrocarbons as xylene; and such halogenated hydrocarbons as
  • organic solvents may be used alone or in combination. Particularly preferred is benzyl alcohol in the invention. These organic solvents are added to the developer or replenisher therefor generally in an amount of not more than 5 % by weight and preferably not more than 4 % by weight.
  • the developers and replenishers used in the present invention may simultaneously contain a surfactant for the purpose of improving developing properties thereof.
  • surfactants include salts of higher alcohol (C 8 ⁇ C 22 ) sulfuric acid esters such as sodium salt of lauryl alcohol sulfate, sodium salt of octyl alcohol sulfate, ammonium salt of lauryl alcohol sulfate, Teepol B-81 (trade mark, available from Shell Chemicals Co., Ltd.) and disodium alkyl sulfates; salts of aliphatic alcohol phosphoric acid esters such as sodium salt of cetyl alcohol phosphate; alkyl aryl sulfonic, acid salts such as sodium salt of dodecylbenzene sulfonate, sodium salt of isopropylnaphthalene sulfonate,sodium salt of dinaphthalene disulfonate and sodium salt of metanitrobenzene sulfonate; sulfonic acid salts of al
  • Examples of such compounds are neutral salts such as NaCl, KCl and KBr as disclosed in JN-A- 58- 75 152; chelating agents such as EDTA and NTA as disclosed in JN-A- 58- 190 952 (U.S-A- 4 469 776), complexes such as [Co(NH 3 ) 6 ]Cl 3 as disclosed in JN-A- 59- 121 336 (US-A- 4 606 995); ionizable compounds of elements of the group IIa, IIIa or IIIb of the Periodic Table such as those disclosed in JN-A- 55- 25 100 ; anionic or amphoteric surfactants such as sodium alkyl naphthalene sulfonate and N-tetradecyl-N,N-dihydroxythyl betaine as disclosed in JN-A- 50- 51 324; tetramethyldecyne diol as disclosed in US-A- 4 374 920; non-ionic
  • any known means of supplementing a replenisher for developer may be employed.
  • Examples of such methods preferably used are a method for intermittently or continuously supplementing a replenisher as a function of the amount of PS plates processed and time as disclosed in JN-A- 55- 115 039 (GB-A- 2 046 931), a method comprising disposing a sensor for detecting the degree of light-sensitive layer dissolved out in the middle portion of a developing zone and supplementing the replenisher in proportion to the detected degree of the light-sensitive layer dissolved out as disclosed in JN-A- 58- 95 349 (US-A- 4 537 496); a method comprising determining the impedance value of a developer and processing the detected impedance value by a computer to perform supplementation of a replenisher as disclosed in GB-A- 2 208 249.
  • the printing plate of the present invention can also be used in the printing process as a seamless sleeve printing plate.
  • the printing plate is soldered in a cylindrical form by means of a laser.
  • This cylindrical printing plate which has as diameter the diameter of the print cylinder is slided on the print cylinder instead of applying in a classical way a classically formed printing plate. More details on sleeves are given in "Grafisch Nieuws" ed. Keesing, 15, 1995, page 4 to 6.
  • the obtained plate After the development of an image-wise exposed imaging element with an aqueous alkaline solution and drying, the obtained plate can be used as a printing plate as such. However, to improve durability it is still possible to bake said plate at a temperature between 200°C and 300°C for a period of 30 seconds to 5 minutes. Also the imaging element can be subjected to an overall post-exposure to UV-radiation to harden the image in order to increase the run lenght of the printing plate.
  • a 0.30 mm thick aluminum foil was degreased by immersing the foil in an aqueous solution containing 5 g/l of sodium hydroxide at 50°C and rinsed with demineralized water.
  • the foil was then electrochemically grained using an alternating current in an aqueous solution containing 4 g/l of hydrochloric acid, 4 g/l of hydroboric acid and 5 g/l of aluminum ions at a temperature of 35°C and a current density of 1200 A/m 2 to form a surface topography with an average center-line roughness Ra of 0.5 ⁇ m.
  • the aluminum foil was then etched with an aqueous solution containing 300 g/l of sulfuric acid at 60°C for 180 seconds and rinsed with demineralized water at 25°C for 30 seconds.
  • the foil was subsequently subjected to anodic oxidation in an aqueous solution containing 200 g/l of sulfuric acid at a temperature of 45°C, a voltage of about 10 V and a current density of 150 A/m 2 for about 300 seconds to form an anodic oxidation film of 3.00 g/m 2 of Al 2 O 3 then washed with demineralized water, posttreated with a solution containing polyvinylphosphonic acid and subsequently with a solution containing aluminum trichloride, rinsed with demineralized water at 20°C during 120 seconds and dried.
  • lithographic base On the lithographic base was first coated a layer from an 8.6% wt solution in tetrahydrofuran/methoxypropanol 55/45 ratio, with a wet coating thickness of 14 ⁇ m.
  • the resulting layer contained 88% of ALNOVOL SPN452 TM and 12% of 3,4,5-trimethoxybenzoic acid.
  • Upon this layer was then coated with a wet coating thickness of 20 ⁇ m, the IR-sensitive layer from a 0.885% wt solution in methylethylketone/methoxypropanol 50/50 ratio. This layer was dried on a temperature of 120°C.
  • the resulting IR-sensitive layer contained 115 mg/m 2 of carbon black, 11.5 mg/m 2 of nitrocellulose, 2.1 mg/m 2 of SOLSPERSE 5000 TM, ( available from Zeneca Specialities, GB) 11.3 mg/m 2 of SOLSPERSE 28000 TM and 14 mg/m 2 of FLUORAD FC 431 TM.
  • FLUORAD FC 431 TM is a non-ionic perfluoroaliphatic polymeric ester, available from 3M,USA.
  • lithographic base of example 1 On the lithographic base of example 1 was first coated a layer from an 8.6% wt solution in tetrahydrofuran/methoxypropanol 55/45 ratio, with a wet coating thickness of 14 ⁇ m. The resulting layer contained 88% of ALNOVOL SPN452 TM and 12% of 3,4,5-trimethoxybenzoic acid. Upon this layer was then coated with a wet coating thickness of 20 ⁇ m, the IR-sensitive layer from a 0.3% wt solution in methylethylketone/methoxypropanol 50/50 ratio. This layer was dried on a temperature of 120°C. .
  • the resulting IR-sensitive layer contained 35 mg/m 2 IR-dye compound 1, 10 mg/m 2 dye BASONYL-BLAU 636 TM (a triarylmethane dye commercially available from BASF), 2 mg/m 2 TEGOGLIDE 265 TM (polyether siloxane copolymer) and 5 mg/m 2 TEGOGLIDE 410 TM (polyether modified polysiloxane) (both silicon surfactants commercially available from Tego Chemie Service GmbH).
  • BASONYL-BLAU 636 TM a triarylmethane dye commercially available from BASF
  • 2 mg/m 2 TEGOGLIDE 265 TM polyether siloxane copolymer
  • 5 mg/m 2 TEGOGLIDE 410 TM polyether modified polysiloxane
  • This material was imaged with a CREO TRENDSETTER 3244-T TM external drum platesetter (available from Creo)at 2400 dpi with an energy-density of 186 mJ/cm 2 at 150 rpm.
  • the IR-exposed areas dissolved very rapidly without any attack in the non IR-exposed areas, resulting in a positive working printing plate.
  • the plate was printed on a Heidelberg GTO46 printing machine with a conventional ink (K+E800) and fountain solution (Rotamatic), resulting in good prints, i.e. no scumming in IR-exposed areas and good ink-uptake in the non imaged areas.
  • K+E800 conventional ink
  • Rotamatic fountain solution
  • the surfactants TEGO GLIDE 265 TM and TEGO GLIDE 410 TM were left out of the IR-sensitive top layer of the heat-mode imaging element 2.
  • This material was imaged with a CREO TRENDSETTER 3244-T TM external drum platesetter at 2400 dpi with an energy-density of 186 mJ/cm 2 at 150 rpm.
  • the material was developer at 1 m/min at 25°C in a TECHNIGRAPH NPX-32T TM processor using OZASOL EP26 TM developer (commercially available from Agfa).

Landscapes

  • Physics & Mathematics (AREA)
  • Optics & Photonics (AREA)
  • Thermal Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Photosensitive Polymer And Photoresist Processing (AREA)
  • Materials For Photolithography (AREA)

Description

FIELD OF THE INVENTION
The present invention relates to a heat mode imaging element for preparing a lithographic printing plate. More specifically the invention is related to a heat mode imaging element for preparing a lithographic printing plate whereof the difference in the top layer of being penetrated and/or solubilised in the exposed areas and in the non-exposed areas by an aqueous developer is increased.
BACKGROUND OF THE INVENTION
Lithography is the process of printing from specially prepared surfaces, some areas of which are capable of accepting lithographic ink, whereas other areas, when moistened with water, will not accept the ink. The areas which accept ink form the printing image areas and the ink-rejecting areas form the background areas.
In the art of photolithography, a photographic material is made imagewise receptive to oily or greasy inks in the photo-exposed (negative-working) or in the non-exposed areas (positive-working) on a hydrophilic background.
In the production of common lithographic printing plates, also called surface litho plates or planographic printing plates, a support that has affinity to water or obtains such affinity by chemical treatment is coated with a thin layer of a photosensitive composition. Coatings for that purpose include light-sensitive polymer layers containing diazo compounds, dichromate-sensitized hydrophilic colloids and a large variety of synthetic photopolymers. Particularly diazo-sensitized systems are widely used.
Upon imagewise exposure of the light-sensitive layer the exposed image areas become insoluble and the unexposed areas remain soluble. The plate is then developed with a suitable liquid to remove the diazonium salt or diazo resin in the unexposed areas.
Alternatively, printing plates are known that include a photosensitive coating that upon image-wise exposure is rendered soluble at the exposed areas. Subsequent development then removes the exposed areas. A typical example of such photosensitive coating is a quinone-diazide based coating.
Typically, the above described photographic materials from which the printing plates are made are camera-exposed through a photographic film that contains the image that is to be reproduced in a lithographic printing process. Such method of working is cumbersome and labor intensive. However, on the other hand, the printing plates thus obtained are of superior lithographic quality.
Attempts have thus been made to eliminate the need for a photographic film in the above process and in particular to obtain a printing plate directly from computer data representing the image to be reproduced. However the photosensitive coating is not sensitive enough to be directly exposed with a laser. Therefor it has been proposed to coat a silver halide layer on top of the photosensitive coating. The silver halide may then directly be exposed by means of a laser under the control of a computer. Subsequently, the silver halide layer is developed leaving a silver image on top of the photosensitive coating. That silver image then serves as a mask in an overall exposure of the photosensitive coating. After the overall exposure the silver image is removed and the photosensitive coating is developed. Such method is disclosed in for example JP-A- 60- 61 752 but has the disadvantage that a complex development and associated developing liquids are needed.
GB-1 492 070 discloses a method wherein a metal layer or a layer containing carbon black is provided on a photosensitive coating. This metal layer is then ablated by means of a laser so that an image mask on the photosensitive layer is obtained. The photosensitive layer is then overall exposed by UV-light through the image mask. After removal of the image mask, the photosensitive layer is developed to obtain a printing plate. This method however still has the disadvantage that the image mask has to be removed prior to development of the photosensitive layer by a cumbersome processing.
Furthermore methods are known for making printing plates involving the use of imaging elements that are heat-sensitive rather than photosensitive. A particular disadvantage of photosensitive imaging elements such as described above for making a printing plate is that they have to be shielded from the light. Furthermore they have a problem of sensitivity in view of the storage stability and they show a lower resolution. The trend towards heat mode printing plate precursors is clearly seen on the market.
For example, Research Disclosure no. 33303 of January 1992 discloses a heat mode imaging element comprising on a support a cross-linked hydrophilic layer containing thermoplastic polymer particles and an infrared absorbing pigment such as e.g. carbon black. By image-wise exposure to an infrared laser, the thermoplastic polymer particles are image-wise coagulated thereby rendering the surface of the imaging element at these areas ink-acceptant without any further development. A disadvantage of this method is that the printing plate obtained is easily damaged since the non-printing areas may become ink accepting when some pressure is applied thereto. Moreover, under critical conditions, the lithographic performance of such a printing plate may be poor and accordingly such printing plate has little lithographic printing latitude.
US-P- 4 708 925 discloses imaging elements including a photosensitive composition comprising an alkali-soluble novolac resin and an onium-salt. This composition may optionally contain an IR-sensitizer. After image-wise exposing said imaging element to UV - visible - or IR-radiation followed by a development step with an aqueous alkali liquid there is obtained a positive or negative working printing plate. The printing results of a lithographic plate obtained by irradiating and developing said imaging element are poor.
EP-A- 625 728 discloses an imaging element comprising a layer which is sensitive to UV- and IR-irradiation and which may be positive or negative working. This layer comprises a resole resin, a novolac resin, a latent Bronsted acid and an IR-absorbing substance. The printing results of a lithographic plate obtained by irradiating and developing said imaging element are poor.
US-P- 5 340 699 is almost identical with EP-A- 625 728 but discloses the method for obtaining a negative working IR-laser recording imaging element. The IR-sensitive layer comprises a resole resin, a novolac resin, a latent Bronsted acid and an IR-absorbing substance. The printing results of a lithographic plate obtained by irradiating and developing said imaging element are poor.
GB-A- 1 208 415 discloses a method of recording information comprising information-wise heating a recording material comprising a support bearing, with or without an interlayer a heat-sensitive recording layer constituted so that such information-wise heating creates a record of the information in terms of a difference in the water permeabilities of different areas of the recording layer, treating the recording material with an aqueous liquid which penetrates through the water-permeable or more water-permeable areas of the recording layer and is constituted so as to effect a permanent physical and/or chemical change of at least the surface portions of the underlying support or inter-layer in the corresponding areas, and removing the whole of the recording layer to expose said information-wise changed support or interlayer.
JP-A-01-46739 discloses a method for preventing the line-like unequalities generated by foam by dissolving a photosensitive composition containing at least a photosensitive material, fluorine surfactant and defoaming agent into a coating solvent, then coating the solution on a base and drying the coating.
JP-A-02-29750 discloses a method for obtaining a photosensitive composition suitable for a positive photosensitive printing plate by using o-naphthoquinonediazide sulphonic acid, an alkali-soluble resin, and a non-ionic surfactant such as polyoxyethylene naphthol.
EP-A- 527.369 discloses a light sensitive recording material comprising a support and a positive working light sensitive layer with a rough surface, which comprises as light sensitive compound at least a 1,2-quinonediazide and as water insoluble and in water-alkaline solutions soluble or swellable binder a polycondensate or polymer and a filler, wherein the light-sensitive layer at a layer weight of 3g/m2 or less (i) comprises as filler silica with a mean diameter from 3 to 5 µm and a final limit of 15 µm in an amount, which yields a slipperiness according to Beck from 20 till 100 seconds and (ii) furthermore comprises a surfactant with polysiloxane units.
EP-A- 823 327 discloses a positive photosensitive composition showing a difference in solubility in an alkali developer as between an exposed portion and a non-exposed portion, which comprises, as components inducing the difference in solubility, (a) a photo-thermal conversion material, and (b) a high molecular compound, of which the solubility in an alkali developer is changeable mainly by a change other than a chemical change.
Furthermore EP-A- 678 380 discloses a method wherein a protective layer is provided on a grained metal support underlying a laser-ablatable surface layer. Upon image-wise exposure the surface layer is fully ablated as well as some parts of the protective layer. The printing plate is then treated with a cleaning solution to remove the residu of the protective layer and thereby exposing the hydrophilic surface layer.
EP-A 864 420, which is prior art under Art 54(3)EPC, discloses the use of Solsperse surfactants, availaible from ICI (later Zeneca, now Avecia Ltd.) in heat-mode lithographic printing plates.
OBJECTS OF THE INVENTION
It is an object of the invention to provide a heat mode imaging element for making in an easy way lithographic printing plates.
It is another object of the invention to provide a heat mode sensitive imaging element for making positive lithographic printing plates having excellent printing properties, developable in a selective, rapid, convenient and ecological way.
It is further an object of the present invention to provide a heat mode sensitive imaging element having a high infrared sensitivity.
It is also an object of the present invention to provide a heat mode sensitive imaging element which has a great difference in developability in a developer between the exposed areas and the non-exposed areas.
Further objects of the present invention will become clear from the description hereinafter.
SUMMARY OF THE INVENTION
According to the present invention there is provided a heat mode imaging element for making a lithographic printing plate having on a lithographic base with a hydrophilic surface a first layer including a polymerthat is soluble in an aqueous alkaline solution and a top layer on the same side of the lithographic base as the first layer that is IR-sensitive and unpenetrable for an alkaline developer; characterized in that at least one of said first layer and said top layer comprises a surfactant, with the proviso that the surfactant is not Solsperse 5000 or Solsperse 28000.
DETAILED DESCRIPTION OF THE INVENTION
It has been found that a heat-sensitive imaging element according to the invention can be obtained in an easy way, which yields a lithographic printing plate of high quality.
The first layer and/or the top (also called the second) layer comprises a surfactant. Said surfactant can be a cationic, an anionic or an amphoteric surfactant, but is preferably a non-ionic surfactant. The surfactant is preferably selected from the group consisting of perfluoroalkyl surfactants, alkylphenyl surfactants and most preferably polysiloxane surfactants. Still more preferably a combination of at least two polysiloxane surfactants is used. The surfactant is preferably present in the top layer. The amount of surfactant lies preferably in the range from 0.001 to 0.3g/m2, more preferably in the range from 0.003 to 0.050g/m2.
The top layer, in accordance with the present invention comprises an IR-dye or pigment and a binder resin. A mixture of IR-dyes or pigments may be used, but it is preferred to use only one IR-dye or pigment. Preferably said IR-dyes are IR-cyanines dyes. Particularly useful IR-cyanine dyes are cyanines dyes with two indolenine groups. Most preferably is compound I with the structure as indicated
Figure 00070001
Particularly useful IR-absorbing pigments are carbon black, metal carbides, borides, nitrides, carbonitrides, bronze-structured oxides and oxides structurally related to the bronze family but lacking the A component e.g. WO2.9. It is also possible to use conductive polymer dispersion such as polypyrrole or polyaniline-based conductive polymer dispersions. The lithographic performance and in particular the print endurance obtained depends on the heat-sensitivity of the imaging element. In this respect it has been found that carbon black yields very good and favorable results.
When said top layer contains an IR-dye, said top layer preferably also contains a dye or a pigment that absorbs in the visible region in order to be able to visually inspect the image formed after IR-radiation and development in an aqueous alkaline developer.
The IR-absorbing dyes or pigments are present preferably in an amount between 1 and 99 parts, more preferably between 50 and 95 parts by weight of the total amount of said IR-sensitive top layer.
The top layer may preferably comprise as binder a water insoluble polymer such as a cellulose ester, a copolymer of vinylidene chloride and acrylonitrile, poly(meth)acrylates, polyvinyl chloride, silicone resins, etc. Preferred as binder is nitrocellulose resin.
The total amount of the top layer preferably ranges from 0.010 to 5 g/m2 more preferably from 0.020 to 1 g/m2.
In the top layer a difference in the capacity of being penetrated and/or solubilised by the aqueous alkaline solution is generated upon image-wise exposure for an alkaline developer according to the invention.
In the present invention the said capacity is increased upon image-wise IR exposure to such degree that the imaged parts will be cleaned out during development without solubilising and/or damaging the non-imaged parts.
The development with the aqueous alkaline solution is preferably done within an interval of 5 to 120 seconds.
Between the top layer and the lithographic base the present invention comprises a first layer soluble in an aqueous developing solution, more preferably an aqueous alkaline developing solution with preferentially a pH between 7.5 and 14. Said layer is preferably contiguous to the top layer but other layers may be present between the top layer and the first layer. The alkali soluble binders used in this layer are preferably hydrophobic binders as used in conventional positive or negative working PS-plates e.g. novolac resins, polymers containing hydroxystyrene units, carboxy substituted polymers etc. Typical examples of these polymers are descibed in DE-A- 4 007 428, DE-A- 4 027 301 and DE-A- 4 445 820. The hydrophobic binder used in connection with the present invention is further characterised by insolubility in water and partial solubility/swellability in an alkaline solution and/or partial solubility in water when combined with a cosolvent.
Furthermore this aqueous alkali soluble layer is preferably a visible light- and UV-light desensitised layer. Said layer is preferably thermally hardenable. This preferably visible light- and UV-desensitised layer does not comprise photosensitive ingredients such as diazo compounds, photoacids, photoinitiators, quinone diazides, sensitisers etc. which absorb in the wavelength range of 250nm to 650nm. In this way a daylight stable printing plate may be obtained.
Said first layer preferably also includes a low molecular acid, preferably a carboxylic acid, still more preferably a benzoic acid, most preferably 3,4,5-trimethoxybenzoic acid or a benzophenone.
The ratio between the total amount of low molecular acid or benzophenone and polymer in the first layer preferably ranges from 2:98 to 40:60, more preferably from 5:95 to 20:80. The total amount of said first layer preferably ranges from 0.1 to 10 g/m2, more preferably from 0.3 to 2 g/m2.
In the imaging element according to the present invention, the lithographic base may be an anodised aluminum. A particularly preferred lithographic base is an electrochemically grained and anodised aluminum support. The anodised aluminum support may be treated to improve the hydrophilic properties of its surface. For example, the aluminum support may be silicated by treating its surface with sodium silicate solution at elevated temperature, e.g. 95°C. Alternatively, a phosphate treatment may be applied which involves treating the aluminum oxide surface with a phosphate solution that may further contain an inorganic fluoride. Further, the aluminum oxide surface may be rinsed with a citric acid or citrate solution. This treatment may be carried out at room temperature or may be carried out at a slightly elevated temperature of about 30 to 50°C. A further interesting treatment involves rinsing the aluminum oxide surface with a bicarbonate solution. Still further, the aluminum oxide surface may be treated with polyvinylphosphonic acid, polyvinylmethylphosphonic acid, phosphoric acid esters of polyvinyl alcohol, polyvinylsulphonic acid, polyvinylbenzenesulphonic acid, sulphuric acid esters of polyvinyl alcohol, and acetals of polyvinyl alcohols formed by reaction with a sulphonated aliphatic aldehyde It is further evident that one or more of these post treatments may be carried out alone or in combination. More detailed descriptions of these treatments are given in GB-A- 1 084 070, DE-A- 4 423 140, DE-A- 4 417 907, EP-A- 659 909, EP-A- 537 633, DE-A- 4 001 466, EP-A- 292 801, EP-A- 291 760 and US-P- 4 458 005.
According to another mode in connection with the present invention, the lithographic base having a hydrophilic surface comprises a flexible support, such as e.g. paper or plastic film, provided with a cross-linked hydrophilic layer. A particularly suitable cross-linked hydrophilic layer may be obtained from a hydrophilic binder cross-linked with a cross-linking agent such as formaldehyde, glyoxal, polyisocyanate or a hydrolysed tetra-alkylorthosilicate. The latter is particularly preferred.
As hydrophilic binder there may be used hydrophilic (co)polymers such as for example, homopolymers and copolymers of vinyl alcohol, acrylamide, methylol acrylamide, methylol methacrylamide, acrylic acid, methacrylic acid, hydroxyethyl acrylate, hydroxyethyl methacrylate or maleic anhydride/vinylmethylether copolymers. The hydrophilicity of the (co)polymer or (co)polymer mixture used is preferably the same as or higher than the hydrophilicity of polyvinyl acetate hydrolyzed to at least an extent of 60 percent by weight, preferably 80 percent by weight.
The amount of crosslinking agent, in particular of tetraalkyl orthosilicate, is preferably at least 0.2 parts by weight per part by weight of hydrophilic binder, more preferably between 0.5 and 5 parts by weight, most preferably between 1.0 parts by weight and 3 parts by weight.
A cross-linked hydrophilic layer in a lithographic base used in accordance with the present embodiment preferably also contains substances that increase the mechanical strength and the porosity of the layer. For this purpose colloidal silica may be used. The colloidal silica employed may be in the form of any commercially available water-dispersion of colloidal silica for example having an average particle size up to 40 nm, e.g. 20 nm. In addition inert particles of larger size than the colloidal silica may be added e.g. silica prepared according to Stöber as described in J. Colloid and Interface Sci., Vol. 26, 1968, pages 62 to 69 or alumina particles or particles having an average diameter of at least 100 nm which are particles of titanium dioxide or other heavy metal oxides. By incorporating these particles the surface of the cross-linked hydrophilic layer is given a uniform rough texture consisting of microscopic hills and valleys, which serve as storage places for water in background areas.
The thickness of a cross-linked hydrophilic layer in a lithographic base in accordance with this embodiment may vary in the range of 0.2 to 25 µm and is preferably 1 to 10 µm.
Particular examples of suitable cross-linked hydrophilic layers for use in accordance with the present invention are disclosed in EP-A- 601 240, GB-P- 1 419 512, FR-P- 2 300 354, US-P- 3 971 660, US-P- 4 284 705 and EP-A- 514 490.
As flexible support of a lithographic base in connection with the present embodiment it is particularly preferred to use a plastic film e.g. substrated polyethylene terephthalate film, cellulose acetate film, polystyrene film, polycarbonate film etc... The plastic film support may be opaque or transparent.
It is particularly preferred to use a polyester film support to which an adhesion improving layer has been provided. Particularly suitable adhesion improving layers for use in accordance with the present invention comprise a hydrophilic binder and colloidal silica as disclosed in EP-A- 619 524, EP-A- 620 502 and EP-A- 619 525. Preferably, the amount of silica in the adhesion improving layer is between 200 mg per m2 and 750 mg per m2. Further, the ratio of silica to hydrophilic binder is preferably more than 1 and the surface area of the colloidal silica is preferably at least 300 m2 per gram, more preferably at least 500 m2 per gram.
Image-wise exposure in connection with the present invention is an image-wise scanning exposure involving the use of a laser that operates in the infrared or near-infrared, i.e. wavelength range of 700-1500 nm. Most preferred are laser diodes emitting in the near-infrared. Exposure of the imaging element may be performed with lasers with a short as well as with lasers with a long pixel dwell time. Preferred are lasers with a pixel dwell time between 0.005 µs and 20 µs.
After the image-wise exposure the heat mode imaging element is developed by rinsing it with an aqueous alkaline solution. The aqueous alkaline solutions used in the present invention are those that are used for developing conventional positive working presensitised printing plates, preferably containing SiO2 in the form of silicates and having preferably a pH between 11.5 and 14. Thus the imaged parts of the top layer that were rendered more penetrable for the aqueous alkaline solution upon exposure are cleaned-out whereby a positive working printing plate is obtained.
In the present invention, the composition of the developer used is also very important.
Therefore, to perform development processing stably for a long time period particularly important are qualities such as strength of alkali and the concentration of silicates in the developer. Under such circumstances, the present inventors have found that a rapid high temperature processing can be performed, that the amount of the replenisher to be supplemented is low and that a stable development processing can be performed over a long time period of the order of not less than 3 months without exchanging the developer only when the developer having the foregoing composition is used.
The developers and replenishers for developer used in the invention are preferably aqueous solutions mainly composed of alkali metal silicates and alkali metal hydroxides represented by MOH or their oxyde, represented by M2O, wherein said developer comprises SiO2 and M2O in a molar ratio .of 0.5 to 1.5 and a concentration of SiO2 of 0.5 to 5% by weight. As such alkali metal silicates, preferably used are, for instance, sodium silicate, potassium silicate, lithium silicate and sodium metasilicate. On the other hand, as such alkali metal hydroxides, preferred are sodium hydroxide, potassium hydroxide and lithium hydroxide.
The developers used in the invention may simultaneously contain other alkaline agents. Examples of such other alkaline agents include such inorganic alkaline agents as ammonium hydroxide, sodium tertiary phosphate, sodium secondary phosphate, potassium tertiary phosphate, potassium secondary phosphate, ammonium tertiary phosphate, ammonium secondary phosphate, sodium bicarbonate, sodium carbonate, potassium carbonate and ammonium carbonate; and such organic alkaline agents as mono-, di- or triethanolamine, mono-, di- or trimethylamine, mono-, di- or triethylamine, mono- or diisopropylamine, n-butylamine, mono-, di- or triisopropanolamine, ethyleneimine, ethylenediimine and tetramethylammonium hydroxide.
In the present invention, particularly important is the molar ratio in the developer of [SiO2] / [M2O], which is generally 0.6 to 1.5, preferably 0.7 to 1.3. This is because if the molar ratio is less than 0.6, great scattering of activity is observed, while if it exceeds 1.5, it becomes difficult to perform rapid development and the dissolving out or removal of the light-sensitive layer on non-image areas is liable to be incomplete. In addition, the concentration of SiO2 in the developer and replenisher preferably ranges from 1 to 4 % by weight. Such limitation of the concentration of SiO2 makes it possible to stably provide lithographic printing plates having good finishing qualities even when a large amount of plates according to the invention are processed for a long time period.
In a particular preferred embodiment, an aqueous solution of an alkali metal silicate having a molar ratio [SiO2] / [M2O], which ranges from 1.0 to 1.5 and a concentration of SiO2 of 1 to 4 % by weight is used as a developer. In such case, it is a matter of course that a replenisher having alkali strength equal to or more than that of the developer is employed. In order to decrease the amount of the replenisher to be supplied, it is advantageous that a molar ratio, [SiO2] / [M2O], of the replenisher is equal to or smaller than that of the developer, or that a concentration of SiO2 is high if the molar ratio of the developer is equal to that of the replenisher.
In the developers and the replenishers used in the invention, it is possible to simultaneously use organic solvents having solubility in water at 20 °C of not more than 10 by weight according to need. Examples of such organic solvents are such carboxilic acid esters as ethyl acetate, propyl acetate, butyl acetate, amyl acetate, benzyl acetate, ethylene glycol monobutyl acetate, butyl lactate and butyl levulinate; such ketones as ethyl butyl ketone, methyl isobutyl ketone and cyclohexanone; such alcohols as ethylene glycol monobutyl ether, ethylene glycol benzyl ether, ethylene glycol monophenyl ether, benzyl alcohol, methylphenylcarbinol, n-amyl alcohol and methylamyl alcohol; such alkyl-substituted aromatic hydrocarbons as xylene; and such halogenated hydrocarbons as methylene dichloride and monochlorobenzene. These organic solvents may be used alone or in combination. Particularly preferred is benzyl alcohol in the invention. These organic solvents are added to the developer or replenisher therefor generally in an amount of not more than 5 % by weight and preferably not more than 4 % by weight.
The developers and replenishers used in the present invention may simultaneously contain a surfactant for the purpose of improving developing properties thereof. Examples of such surfactants include salts of higher alcohol (C8 ~ C22) sulfuric acid esters such as sodium salt of lauryl alcohol sulfate, sodium salt of octyl alcohol sulfate, ammonium salt of lauryl alcohol sulfate, Teepol B-81 (trade mark, available from Shell Chemicals Co., Ltd.) and disodium alkyl sulfates; salts of aliphatic alcohol phosphoric acid esters such as sodium salt of cetyl alcohol phosphate; alkyl aryl sulfonic, acid salts such as sodium salt of dodecylbenzene sulfonate, sodium salt of isopropylnaphthalene sulfonate,sodium salt of dinaphthalene disulfonate and sodium salt of metanitrobenzene sulfonate; sulfonic acid salts of alkylamides such as C17H33CON(CH3)CH2CH2SO3Na and sulfonic acid salts of dibasic aliphatic acid esters such as sodium dioctyl sulfosuccinate and sodium dihexyl sulfosuccinate. These surfactants may be used alone or in combination. Particularly preferred are sulfonic acid salts. These surfactants may be used in an amount of generally not more than 5 % by weight and preferably not more than 3 % by weight.
In order to enhance developing stability of the developers and replenishers used in the invention, the following compounds may simultaneously be used.
Examples of such compounds are neutral salts such as NaCl, KCl and KBr as disclosed in JN-A- 58- 75 152; chelating agents such as EDTA and NTA as disclosed in JN-A- 58- 190 952 (U.S-A- 4 469 776), complexes such as [Co(NH3)6]Cl3 as disclosed in JN-A- 59- 121 336 (US-A- 4 606 995); ionizable compounds of elements of the group IIa, IIIa or IIIb of the Periodic Table such as those disclosed in JN-A- 55- 25 100; anionic or amphoteric surfactants such as sodium alkyl naphthalene sulfonate and N-tetradecyl-N,N-dihydroxythyl betaine as disclosed in JN-A- 50- 51 324; tetramethyldecyne diol as disclosed in US-A- 4 374 920; non-ionic surfactants as disclosed in JN-A- 60- 213 943; cationic polymers such as methyl chloride quaternary products of p-dimethylaminomethyl polystyrene as disclosed in JN-A- 55- 95 946; amphoteric polyelectrolytes such as copolymer of vinylbenzyl trimethylammonium chloride and sodium acrylate as disclosed in JN-A- 56- 142 528; reducing inorganic salts such as sodium sulfite as disclosed in JN-A- 57- 192 952 (US-A- 4 467 027) and alkaline-soluble mercapto compounds or thioether compounds such as thiosalicylic acid, cysteine and thioglycolic acid; inorganic lithium compounds such as lithium chloride as disclosed in JN-A- 58- 59 444; organic lithium compounds such as lithium benzoate as disclosed in JN-A- 50 34 442; organometallic surfactants containing Si, Ti or the like as disclosed in JN-A- 59- 75 255; organoboron compounds as disclosed in JN-A- 59- 84 241 (US-A- 4 500 625); quaternary ammonium salts such as tetraalkylammonium oxides as disclosed in EP-A- 101 010; and bactericides such as sodium dehydroacetate as disclosed in JN-A- 63- 226 657.
In the method for development processing of the present invention, any known means of supplementing a replenisher for developer may be employed. Examples of such methods preferably used are a method for intermittently or continuously supplementing a replenisher as a function of the amount of PS plates processed and time as disclosed in JN-A- 55- 115 039 (GB-A- 2 046 931), a method comprising disposing a sensor for detecting the degree of light-sensitive layer dissolved out in the middle portion of a developing zone and supplementing the replenisher in proportion to the detected degree of the light-sensitive layer dissolved out as disclosed in JN-A- 58- 95 349 (US-A- 4 537 496); a method comprising determining the impedance value of a developer and processing the detected impedance value by a computer to perform supplementation of a replenisher as disclosed in GB-A- 2 208 249.
The printing plate of the present invention can also be used in the printing process as a seamless sleeve printing plate. In this option the printing plate is soldered in a cylindrical form by means of a laser. This cylindrical printing plate which has as diameter the diameter of the print cylinder is slided on the print cylinder instead of applying in a classical way a classically formed printing plate. More details on sleeves are given in "Grafisch Nieuws" ed. Keesing, 15, 1995, page 4 to 6.
After the development of an image-wise exposed imaging element with an aqueous alkaline solution and drying, the obtained plate can be used as a printing plate as such. However, to improve durability it is still possible to bake said plate at a temperature between 200°C and 300°C for a period of 30 seconds to 5 minutes. Also the imaging element can be subjected to an overall post-exposure to UV-radiation to harden the image in order to increase the run lenght of the printing plate.
The following examples illustrate the present invention without limiting it thereto. All parts and percentages are by weight unless otherwise specified.
Examples Example 1 Preparation of the lithographic base
A 0.30 mm thick aluminum foil was degreased by immersing the foil in an aqueous solution containing 5 g/l of sodium hydroxide at 50°C and rinsed with demineralized water. The foil was then electrochemically grained using an alternating current in an aqueous solution containing 4 g/l of hydrochloric acid, 4 g/l of hydroboric acid and 5 g/l of aluminum ions at a temperature of 35°C and a current density of 1200 A/m2 to form a surface topography with an average center-line roughness Ra of 0.5 µm.
After rinsing with demineralized water the aluminum foil was then etched with an aqueous solution containing 300 g/l of sulfuric acid at 60°C for 180 seconds and rinsed with demineralized water at 25°C for 30 seconds.
The foil was subsequently subjected to anodic oxidation in an aqueous solution containing 200 g/l of sulfuric acid at a temperature of 45°C, a voltage of about 10 V and a current density of 150 A/m2 for about 300 seconds to form an anodic oxidation film of 3.00 g/m2 of Al2O3 then washed with demineralized water, posttreated with a solution containing polyvinylphosphonic acid and subsequently with a solution containing aluminum trichloride, rinsed with demineralized water at 20°C during 120 seconds and dried.
Preparation of the heat-mode imaging element 1.
On the lithographic base was first coated a layer from an 8.6% wt solution in tetrahydrofuran/methoxypropanol 55/45 ratio, with a wet coating thickness of 14µm. The resulting layer contained 88% of ALNOVOL SPN452 ™ and 12% of 3,4,5-trimethoxybenzoic acid.
Upon this layer was then coated with a wet coating thickness of 20µm, the IR-sensitive layer from a 0.885% wt solution in methylethylketone/methoxypropanol 50/50 ratio. This layer was dried on a temperature of 120°C.
The resulting IR-sensitive layer contained 115 mg/m2 of carbon black, 11.5 mg/m2 of nitrocellulose, 2.1 mg/m2 of SOLSPERSE 5000 ™, ( available from Zeneca Specialities, GB) 11.3 mg/m2 of SOLSPERSE 28000 ™ and 14 mg/m2 of FLUORAD FC 431 ™.
FLUORAD FC 431 ™ is a non-ionic perfluoroaliphatic polymeric ester, available from 3M,USA.
Example 2 Preparation of the heat-mode imaging element 2.
On the lithographic base of example 1 was first coated a layer from an 8.6% wt solution in tetrahydrofuran/methoxypropanol 55/45 ratio, with a wet coating thickness of 14µm. The resulting layer contained 88% of ALNOVOL SPN452 ™ and 12% of 3,4,5-trimethoxybenzoic acid.
Upon this layer was then coated with a wet coating thickness of 20µm, the IR-sensitive layer from a 0.3% wt solution in methylethylketone/methoxypropanol 50/50 ratio. This layer was dried on a temperature of 120°C.
. The resulting IR-sensitive layer contained 35 mg/m2 IR-dye compound 1, 10 mg/m2 dye BASONYL-BLAU 636 ™ (a triarylmethane dye commercially available from BASF), 2 mg/m2 TEGOGLIDE 265 ™ (polyether siloxane copolymer) and 5 mg/m2 TEGOGLIDE 410 ™ (polyether modified polysiloxane) (both silicon surfactants commercially available from Tego Chemie Service GmbH).
This material was imaged with a CREO TRENDSETTER 3244-T ™ external drum platesetter (available from Creo)at 2400 dpi with an energy-density of 186 mJ/cm2 at 150 rpm.
After IR-imaging the material was developed at 1 m/min at 25°C in a TECHNIGRAPH NPX-32T ™ processor using OZASOL EP26 ™ developer (commercially available from Agfa).
The IR-exposed areas dissolved very rapidly without any attack in the non IR-exposed areas, resulting in a positive working printing plate.
The plate was printed on a Heidelberg GTO46 printing machine with a conventional ink (K+E800) and fountain solution (Rotamatic), resulting in good prints, i.e. no scumming in IR-exposed areas and good ink-uptake in the non imaged areas.
Comparative heat-mode imaging element 3:
In this comparative element 3 the surfactants TEGO GLIDE 265 ™ and TEGO GLIDE 410 ™ were left out of the IR-sensitive top layer of the heat-mode imaging element 2. This material was imaged with a CREO TRENDSETTER 3244-T ™ external drum platesetter at 2400 dpi with an energy-density of 186 mJ/cm2 at 150 rpm.
After IR-imaging the material was developer at 1 m/min at 25°C in a TECHNIGRAPH NPX-32T ™ processor using OZASOL EP26 ™ developer (commercially available from Agfa).
The IR-exposed areas dissolved very rapidly with severe attack of the non IR-exposed areas, resulting in a useless printing plate.
Printed on a Heidelberg GTO46 printing machine with a conventional ink (K+E800) and fountain solution (Rotamatic), the plate gave no good printing result i.e. no good ink-uptake in the non imaged areas.
Results: Density of the layer and Dmax / Dmin after imaging and processing were measured with MacBeth 918SB cyan filter).
Figure 00190001

Claims (10)

  1. A heat mode imaging element for making a lithographic printing plate having on a lithographic base with a hydrophilic surface a first layer including a polymer that is soluble in an aqueous alkaline solution and a top layer on the same side of the lithographic base as the first layer that is IR-sensitive and unpenetrable for an alkaline developer; characterized in that at least one of said first layer and said top layer comprises a surfactant, with the proviso that the surfactant is not Solsperse 5000 or Solsperse 28000.
  2. A heat mode imaging element for making a lithographic printing plate according to claim 1 wherein said surfactant is a surfactant selected from the group consisting of perfluoroalkyl surfactants, and alkylphenyl surfactants.
  3. A heat mode imaging element for making a lithographic printing plate according to claim 1 wherein said surfactant is a polysiloxane surfactant.
  4. A heat mode imaging element for making a lithographic printing plate according to any of claims 1 to 3 wherein the surfactant is present in an amount ranging from 0.003 to 0.050 g/m2.
  5. A heat mode imaging element for making a lithographic printing plate according to any of claims 1 to 4 wherein said polymer included in the first layer is a hydrophobic polymer.
  6. A heat mode imaging element for making a lithographic printing plate according to claim 5 wherein said hydrophobic polymer is a novolac resin or a polymer comprising hydroxystyrene units.
  7. A heat mode imaging element for making a lithographic printing plate according to any of claims 1 to 6 wherein said first layer comprises a compound selected from the group consisting of low molecular acids and benzophenones.
  8. A heat mode imaging element for making a lithographic printing plate according to any of claims 1 to 7 wherein the lithographic base is an electrochemically grained and anodised aluminum support.
  9. A heat mode imaging element for making a lithographic printing plate according to claim 8 wherein the electrochemically grained and anodised aluminum support has been treated with polyvinylphosphonic acid, polyvinylmethylphosphonic acid, phosphoric acid esters of polyvinyl alcohol, polyvinylsulphonic acid, polyvinylbenzenesulphonic acid, sulphuric acid esters of polyvinyl alcohol, and acetals of polyvinyl alcohols formed by reaction with a sulphonated aliphatic aldehyde.
  10. A method for making a lithographic printing plate comprising the steps of:
    a) exposing imagewise a heat mode imaging element according to any of claims 1 to 9 to IR-radiation;
    b) developing said imagewise exposed heat mode imaging element with an aqueous alkaline developer so that the exposed areas of the top layer and the underlying areas of the first layer are dissolved and the unexposed areas of the first layer remain undissolved.
EP19990200511 1998-04-15 1999-02-23 A heat mode sensitive imaging element for making positive working printing plates Expired - Lifetime EP0950518B1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
EP19990200511 EP0950518B1 (en) 1998-04-15 1999-02-23 A heat mode sensitive imaging element for making positive working printing plates

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
EP98201215 1998-04-15
EP98201215 1998-04-15
EP19990200511 EP0950518B1 (en) 1998-04-15 1999-02-23 A heat mode sensitive imaging element for making positive working printing plates

Publications (2)

Publication Number Publication Date
EP0950518A1 EP0950518A1 (en) 1999-10-20
EP0950518B1 true EP0950518B1 (en) 2002-01-23

Family

ID=26150236

Family Applications (1)

Application Number Title Priority Date Filing Date
EP19990200511 Expired - Lifetime EP0950518B1 (en) 1998-04-15 1999-02-23 A heat mode sensitive imaging element for making positive working printing plates

Country Status (1)

Country Link
EP (1) EP0950518B1 (en)

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6893783B2 (en) 2003-10-08 2005-05-17 Kodak Polychrome Graphics Lld Multilayer imageable elements
US6942957B2 (en) 2003-07-17 2005-09-13 Kodak Polychrome Graphics Llc Ionic liquids as developability enhancing agents in multilayer imageable elements
US7049045B2 (en) 2003-08-14 2006-05-23 Kodak Polychrome Graphics Llc Multilayer imageable elements
US7163777B2 (en) 2001-09-07 2007-01-16 Eastman Kodak Company Thermally sensitive imageable element
US7229744B2 (en) 2003-03-21 2007-06-12 Eastman Kodak Company Method for preparing lithographic printing plates
CN103879169A (en) * 2012-12-24 2014-06-25 乐凯华光印刷科技有限公司 Positive image thermo-sensitive CTP printing plate material capable of resisting UV printing ink

Families Citing this family (36)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP4137345B2 (en) * 2000-06-05 2008-08-20 富士フイルム株式会社 Planographic printing plate precursor
JP2002023350A (en) 2000-07-07 2002-01-23 Fuji Photo Film Co Ltd Negative type original plate of planographic printing plate
JP4512281B2 (en) 2001-02-22 2010-07-28 富士フイルム株式会社 Negative type planographic printing plate precursor
US6613494B2 (en) 2001-03-13 2003-09-02 Kodak Polychrome Graphics Llc Imageable element having a protective overlayer
JP4266077B2 (en) 2001-03-26 2009-05-20 富士フイルム株式会社 Planographic printing plate precursor and planographic printing method
US6846613B2 (en) * 2001-04-09 2005-01-25 Agfa-Gevaert Positive-working lithographic printing plate precursors
EP1275498A3 (en) * 2001-07-09 2005-05-04 Fuji Photo Film Co., Ltd. Lithographic printing plate precursor and production method of lithographic printing plate
US6593055B2 (en) 2001-09-05 2003-07-15 Kodak Polychrome Graphics Llc Multi-layer thermally imageable element
US6723490B2 (en) 2001-11-15 2004-04-20 Kodak Polychrome Graphics Llc Minimization of ablation in thermally imageable elements
US6699636B2 (en) 2001-12-12 2004-03-02 Kodak Polychrome Graphics Llc Imaging element comprising a thermally activated crosslinking agent
US6852464B2 (en) 2002-01-10 2005-02-08 Kodak Polychrome Graphics, Llc Method of manufacturing a thermally imageable element
US6830862B2 (en) 2002-02-28 2004-12-14 Kodak Polychrome Graphics, Llc Multi-layer imageable element with a crosslinked top layer
US6887642B2 (en) 2002-04-05 2005-05-03 Kodak Polychrome Graphies Llc Multi-layer negative working imageable element
US6849372B2 (en) 2002-07-30 2005-02-01 Kodak Polychrome Graphics Method of manufacturing imaging compositions
DE60327141D1 (en) 2002-09-30 2009-05-28 Fujifilm Corp Polymerizable composition and planographic printing plate precursor
JP2004126050A (en) 2002-09-30 2004-04-22 Fuji Photo Film Co Ltd Lithographic printing original plate
JP4137577B2 (en) 2002-09-30 2008-08-20 富士フイルム株式会社 Photosensitive composition
US20060234161A1 (en) 2002-10-04 2006-10-19 Eric Verschueren Method of making a lithographic printing plate precursor
US6858359B2 (en) 2002-10-04 2005-02-22 Kodak Polychrome Graphics, Llp Thermally sensitive, multilayer imageable element
US6803167B2 (en) 2002-12-04 2004-10-12 Kodak Polychrome Graphics, Llc Preparation of lithographic printing plates
CN100590525C (en) 2002-12-18 2010-02-17 富士胶片株式会社 Polymerizable composition and plated printed plate fore-body
JP4150261B2 (en) 2003-01-14 2008-09-17 富士フイルム株式会社 Plate making method of lithographic printing plate precursor
JP2004252201A (en) 2003-02-20 2004-09-09 Fuji Photo Film Co Ltd Lithographic printing original plate
US6844141B1 (en) 2003-07-23 2005-01-18 Kodak Polychrome Graphics Llc Method for developing multilayer imageable elements
US6992688B2 (en) 2004-01-28 2006-01-31 Eastman Kodak Company Method for developing multilayer imageable elements
JP4299639B2 (en) 2003-07-29 2009-07-22 富士フイルム株式会社 Polymerizable composition and image recording material using the same
JP2005099284A (en) 2003-09-24 2005-04-14 Fuji Photo Film Co Ltd Photosensitive composition and planographic printing original plate
US7297465B2 (en) 2003-12-18 2007-11-20 Agfa Graphics Nv Heat-sensitive lithographic printing plate precursor
EP2065211B1 (en) 2007-11-30 2010-05-26 Agfa Graphics N.V. A method for treating a lithographic printing plate
EP2098376B1 (en) 2008-03-04 2013-09-18 Agfa Graphics N.V. A method for making a lithographic printing plate support
EP2106924B1 (en) 2008-03-31 2011-06-29 Agfa Graphics N.V. A method for treating a lithographic printing plate
EP2213690B1 (en) 2009-01-30 2015-11-11 Agfa Graphics N.V. A new alkali soluble resin
EP2263874B1 (en) 2009-06-18 2012-04-18 Agfa Graphics N.V. A lithographic printing plate precursor
EP2329951B1 (en) 2009-12-04 2012-06-20 AGFA Graphics NV A lithographic printing plate precursor
EP2489512B1 (en) 2011-02-18 2013-08-28 Agfa Graphics N.V. A lithographic printing plate precursor
EP3170662B1 (en) 2015-11-20 2019-08-14 Agfa Nv A lithographic printing plate precursor

Family Cites Families (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1208415A (en) * 1966-10-24 1970-10-14 Agfa Gevaert Nv Improvements relating to thermo-copying
JPS6446739A (en) * 1987-08-14 1989-02-21 Konishiroku Photo Ind Production of photosensitive planographic printing plate
JPH0229750A (en) * 1988-07-20 1990-01-31 Mitsubishi Kasei Corp Photosensitive composition and photosensitive planographic printing plate
DE4126836A1 (en) * 1991-08-14 1993-02-18 Hoechst Ag RADIATION-SENSITIVE RECORDING MATERIAL FROM LAYER SUPPORT AND POSITIVELY WORKING, RADIATION-SENSITIVE LAYER WITH ROUGH SURFACE
EP0685333A2 (en) * 1992-06-05 1995-12-06 Agfa-Gevaert N.V. A heat mode recording material and method for producing driographic printing plates
JP3814961B2 (en) * 1996-08-06 2006-08-30 三菱化学株式会社 Positive photosensitive printing plate
EP0864420B2 (en) * 1997-03-11 2005-11-16 Agfa-Gevaert Heat-sensitive imaging element for making positive working printing plates

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7163777B2 (en) 2001-09-07 2007-01-16 Eastman Kodak Company Thermally sensitive imageable element
US7229744B2 (en) 2003-03-21 2007-06-12 Eastman Kodak Company Method for preparing lithographic printing plates
US6942957B2 (en) 2003-07-17 2005-09-13 Kodak Polychrome Graphics Llc Ionic liquids as developability enhancing agents in multilayer imageable elements
US7049045B2 (en) 2003-08-14 2006-05-23 Kodak Polychrome Graphics Llc Multilayer imageable elements
US6893783B2 (en) 2003-10-08 2005-05-17 Kodak Polychrome Graphics Lld Multilayer imageable elements
US7060415B2 (en) 2003-10-08 2006-06-13 Kodak Polychrome Graphics Llc Printing plate precursor comprising solvent-resistant copolymer
CN103879169A (en) * 2012-12-24 2014-06-25 乐凯华光印刷科技有限公司 Positive image thermo-sensitive CTP printing plate material capable of resisting UV printing ink
CN103879169B (en) * 2012-12-24 2016-05-04 乐凯华光印刷科技有限公司 A kind of positive-printing heat-sensitive CTP plate material of the ink of resistance to UV

Also Published As

Publication number Publication date
EP0950518A1 (en) 1999-10-20

Similar Documents

Publication Publication Date Title
EP0950518B1 (en) A heat mode sensitive imaging element for making positive working printing plates
EP0950517B1 (en) A heat mode sensitive imaging element for making positive working printing plates
EP1025992B1 (en) A method for making positive printing plates
US6153353A (en) Method for making positive working printing plates from a heat mode sensitive imaging element
US6083663A (en) Method for making positive working printing plates from a heat mode sensitive image element
US6004728A (en) Method for making positive working printing plates from a heat mode sensitive image element
EP0908305B1 (en) A method for making positive working printing plates from a heat mode sensitive imaging element
EP1023994B1 (en) A heat mode sensitive imaging element for making positive working printing plates.
EP0908779B1 (en) A method for making positive working printing plates from a heat mode sensitive imaging element
EP0943451B1 (en) A heat mode imaging element and a method for making positive working printing plates from said heat mode imaging element
US6340815B1 (en) Heat mode sensitive imaging element for making positive working printing plates
US6192799B1 (en) Heat mode sensitive imaging element for making positive working printing plates
EP0950514B1 (en) A heat mode sensitive imaging element for making positive working printing plates
US6472119B1 (en) Heat mode sensitive imaging element for making positive working printing plates
US6251563B1 (en) Method for making positive working printing plates from a heat mode sensitive image element
EP0997272B1 (en) A heat mode sensitive imaging element for making positive working printing plates
US6569594B2 (en) Heat mode sensitive imaging element for making positive working printing plates
EP0950513B1 (en) A heat mode sensitive imaging element for making positive working printing plates
EP1025991B1 (en) A method for making positive working printing plates
US6458510B1 (en) Method for making positive working printing plates
EP0950516B1 (en) A heat mode sensitive imaging element for making positive working printing plates
EP0908304B1 (en) A method for making positive working printing plates from a heat mode sensitive imaging element
EP0914941B1 (en) A method for making positive working printing plates from heat mode sensitive imaging element
US6489079B1 (en) Heat mode sensitive imaging element for making positive working printing plates
US6455229B1 (en) Method for making positive working printing plates

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): DE FR GB

AX Request for extension of the european patent

Free format text: AL;LT;LV;MK;RO;SI

17P Request for examination filed

Effective date: 20000420

AKX Designation fees paid

Free format text: DE FR GB

17Q First examination report despatched

Effective date: 20001201

GRAG Despatch of communication of intention to grant

Free format text: ORIGINAL CODE: EPIDOS AGRA

GRAG Despatch of communication of intention to grant

Free format text: ORIGINAL CODE: EPIDOS AGRA

GRAH Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOS IGRA

GRAH Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOS IGRA

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

REG Reference to a national code

Ref country code: GB

Ref legal event code: IF02

AK Designated contracting states

Kind code of ref document: B1

Designated state(s): DE FR GB

RAP2 Party data changed (patent owner data changed or rights of a patent transferred)

Owner name: AGFA-GEVAERT

REF Corresponds to:

Ref document number: 69900799

Country of ref document: DE

Date of ref document: 20020314

ET Fr: translation filed
PLBE No opposition filed within time limit

Free format text: ORIGINAL CODE: 0009261

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT

26N No opposition filed
REG Reference to a national code

Ref country code: GB

Ref legal event code: 732E

REG Reference to a national code

Ref country code: FR

Ref legal event code: TP

REG Reference to a national code

Ref country code: GB

Ref legal event code: S75Z

Free format text: APPLICATION OPEN FOR OPPOSITION

REG Reference to a national code

Ref country code: GB

Ref legal event code: S75Z

Free format text: APPLICATION WITHDRAWN; APPLICATION TO AMEND UNDER SECTION 75 FILED ON 15 APRIL 2009 DISCONTINUED ON 7 OCTOBER 2009 (HC09C01139)

Ref country code: GB

Ref legal event code: S27

Free format text: APPLICATION FILED; APPLICATION TO AMEND SPECIFICATION UNDER SECTION 27 FILED ON 29 OCTOBER 2009

REG Reference to a national code

Ref country code: GB

Ref legal event code: S27

Free format text: APPLICATION OPEN FOR OPPOSITION

REG Reference to a national code

Ref country code: GB

Ref legal event code: 732E

Free format text: REGISTERED BETWEEN 20100401 AND 20100407

REG Reference to a national code

Ref country code: FR

Ref legal event code: TQ

REG Reference to a national code

Ref country code: GB

Ref legal event code: 732E

Free format text: REGISTERED BETWEEN 20100722 AND 20100728

REG Reference to a national code

Ref country code: GB

Ref legal event code: S27

Free format text: SPECIFICATION AMENDED; APPLICATION FOR AMENDMENT UNDER SECTION 27 FILED ON 29 OCTOBER 2009, ALLOWED ON 17 FEBRUARY 2011

REG Reference to a national code

Ref country code: DE

Ref legal event code: R081

Ref document number: 69900799

Country of ref document: DE

Owner name: AGFA NV, BE

Free format text: FORMER OWNER: AGFA GRAPHICS N.V., MORTSEL, BE

Effective date: 20120403

Ref country code: DE

Ref legal event code: R081

Ref document number: 69900799

Country of ref document: DE

Owner name: AGFA GRAPHICS N.V., BE

Free format text: FORMER OWNER: AGFA GRAPHICS N.V., MORTSEL, BE

Effective date: 20120403

Ref country code: DE

Ref legal event code: R081

Ref document number: 69900799

Country of ref document: DE

Owner name: EASTMAN KODAK COMPANY (N.D.GES.D. STAATES DELA, US

Free format text: FORMER OWNER: AGFA GRAPHICS N.V., MORTSEL, BE

Effective date: 20120403

REG Reference to a national code

Ref country code: DE

Ref legal event code: R082

Ref document number: 69900799

Country of ref document: DE

Representative=s name: RAU, SCHNECK & HUEBNER PATENTANWAELTE RECHTSAN, DE

REG Reference to a national code

Ref country code: DE

Ref legal event code: R082

Ref document number: 69900799

Country of ref document: DE

Representative=s name: RAU, SCHNECK & HUEBNER PATENTANWAELTE RECHTSAN, DE

Effective date: 20140314

Ref country code: DE

Ref legal event code: R081

Ref document number: 69900799

Country of ref document: DE

Owner name: AGFA NV, BE

Free format text: FORMER OWNERS: AGFA GRAPHICS N.V., MORTSEL, BE; PAKON INC., MINNETONKA, MINN., US

Effective date: 20140314

Ref country code: DE

Ref legal event code: R081

Ref document number: 69900799

Country of ref document: DE

Owner name: AGFA GRAPHICS N.V., BE

Free format text: FORMER OWNERS: AGFA GRAPHICS N.V., MORTSEL, BE; PAKON INC., MINNETONKA, MINN., US

Effective date: 20140314

Ref country code: DE

Ref legal event code: R081

Ref document number: 69900799

Country of ref document: DE

Owner name: EASTMAN KODAK COMPANY (N.D.GES.D. STAATES DELA, US

Free format text: FORMER OWNERS: AGFA GRAPHICS N.V., MORTSEL, BE; PAKON INC., MINNETONKA, MINN., US

Effective date: 20140314

Ref country code: DE

Ref legal event code: R081

Ref document number: 69900799

Country of ref document: DE

Owner name: EASTMAN KODAK COMPANY (N.D.GES.D. STAATES DELA, US

Free format text: FORMER OWNER: AGFA GRAPHICS N.V., PAKON INC., , US

Effective date: 20140314

Ref country code: DE

Ref legal event code: R081

Ref document number: 69900799

Country of ref document: DE

Owner name: AGFA GRAPHICS N.V., BE

Free format text: FORMER OWNER: AGFA GRAPHICS N.V., PAKON INC., , US

Effective date: 20140314

REG Reference to a national code

Ref country code: FR

Ref legal event code: TQ

Owner name: AGFA GRAPHICS NV, BE

Effective date: 20140328

Ref country code: FR

Ref legal event code: TQ

Owner name: EASTMAN KODAK COMPANY, US

Effective date: 20140328

REG Reference to a national code

Ref country code: GB

Ref legal event code: 732E

Free format text: REGISTERED BETWEEN 20140605 AND 20140611

REG Reference to a national code

Ref country code: FR

Ref legal event code: PLFP

Year of fee payment: 18

REG Reference to a national code

Ref country code: FR

Ref legal event code: PLFP

Year of fee payment: 19

REG Reference to a national code

Ref country code: FR

Ref legal event code: PLFP

Year of fee payment: 20

REG Reference to a national code

Ref country code: DE

Ref legal event code: R082

Ref document number: 69900799

Country of ref document: DE

Representative=s name: RAU, SCHNECK & HUEBNER PATENTANWAELTE RECHTSAN, DE

Ref country code: DE

Ref legal event code: R081

Ref document number: 69900799

Country of ref document: DE

Owner name: EASTMAN KODAK COMPANY (N.D.GES.D. STAATES DELA, US

Free format text: FORMER OWNERS: AGFA GRAPHICS N.V., MORTSEL, BE; EASTMAN KODAK COMPANY (N.D.GES.D. STAATES DELAWARE), ROCHESTER, N.Y., US

Ref country code: DE

Ref legal event code: R081

Ref document number: 69900799

Country of ref document: DE

Owner name: AGFA NV, BE

Free format text: FORMER OWNERS: AGFA GRAPHICS N.V., MORTSEL, BE; EASTMAN KODAK COMPANY (N.D.GES.D. STAATES DELAWARE), ROCHESTER, N.Y., US

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: FR

Payment date: 20171214

Year of fee payment: 20

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: GB

Payment date: 20171214

Year of fee payment: 20

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: DE

Payment date: 20171214

Year of fee payment: 20

REG Reference to a national code

Ref country code: FR

Ref legal event code: CD

Owner name: AGFA NV, BE

Effective date: 20180628

Ref country code: FR

Ref legal event code: CD

Owner name: EASTMAN KODAK COMPANY, US

Effective date: 20180628

REG Reference to a national code

Ref country code: DE

Ref legal event code: R071

Ref document number: 69900799

Country of ref document: DE

REG Reference to a national code

Ref country code: GB

Ref legal event code: PE20

Expiry date: 20190222

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: GB

Free format text: LAPSE BECAUSE OF EXPIRATION OF PROTECTION

Effective date: 20190222