EP1243413B1 - Verfahren zur Herstellung einer negativarbeitenden, wärmeempfindlichen, lithographischen Druckplattenvorstufe - Google Patents

Verfahren zur Herstellung einer negativarbeitenden, wärmeempfindlichen, lithographischen Druckplattenvorstufe Download PDF

Info

Publication number
EP1243413B1
EP1243413B1 EP20020100128 EP02100128A EP1243413B1 EP 1243413 B1 EP1243413 B1 EP 1243413B1 EP 20020100128 EP20020100128 EP 20020100128 EP 02100128 A EP02100128 A EP 02100128A EP 1243413 B1 EP1243413 B1 EP 1243413B1
Authority
EP
European Patent Office
Prior art keywords
polymer
image
temperature
particles
printing plate
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
EP20020100128
Other languages
English (en)
French (fr)
Other versions
EP1243413A1 (de
Inventor
Joan Vermeersch
Marc Van Damme
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
Agfa Gevaert AG
Original Assignee
Agfa Gevaert NV
Agfa Gevaert AG
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
Priority claimed from EP01000059A external-priority patent/EP1243410A1/de
Application filed by Agfa Gevaert NV, Agfa Gevaert AG filed Critical Agfa Gevaert NV
Priority to EP20020100128 priority Critical patent/EP1243413B1/de
Publication of EP1243413A1 publication Critical patent/EP1243413A1/de
Application granted granted Critical
Publication of EP1243413B1 publication Critical patent/EP1243413B1/de
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
    • B41C—PROCESSES FOR THE MANUFACTURE OR REPRODUCTION OF PRINTING SURFACES
    • B41C1/00—Forme preparation
    • B41C1/10—Forme preparation for lithographic printing; Master sheets for transferring a lithographic image to the forme
    • B41C1/1008—Forme 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
    • B41C1/1025—Forme 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 using materials comprising a polymeric matrix containing a polymeric particulate material, e.g. hydrophobic heat coalescing particles
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
    • B41C—PROCESSES FOR THE MANUFACTURE OR REPRODUCTION OF PRINTING SURFACES
    • B41C2210/00—Preparation or type or constituents of the imaging layers, in relation to lithographic printing forme preparation
    • B41C2210/04—Negative working, i.e. the non-exposed (non-imaged) areas are removed
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
    • B41C—PROCESSES FOR THE MANUFACTURE OR REPRODUCTION OF PRINTING SURFACES
    • B41C2210/00—Preparation or type or constituents of the imaging layers, in relation to lithographic printing forme preparation
    • B41C2210/06—Developable by an alkaline solution
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
    • B41C—PROCESSES FOR THE MANUFACTURE OR REPRODUCTION OF PRINTING SURFACES
    • B41C2210/00—Preparation or type or constituents of the imaging layers, in relation to lithographic printing forme preparation
    • B41C2210/22—Preparation 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
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
    • B41C—PROCESSES FOR THE MANUFACTURE OR REPRODUCTION OF PRINTING SURFACES
    • B41C2210/00—Preparation or type or constituents of the imaging layers, in relation to lithographic printing forme preparation
    • B41C2210/24—Preparation 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
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
    • B41C—PROCESSES FOR THE MANUFACTURE OR REPRODUCTION OF PRINTING SURFACES
    • B41C2210/00—Preparation or type or constituents of the imaging layers, in relation to lithographic printing forme preparation
    • B41C2210/26—Preparation 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
    • B41C2210/262—Phenolic condensation polymers, e.g. novolacs, resols
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
    • B41M—PRINTING, DUPLICATING, MARKING, OR COPYING PROCESSES; COLOUR PRINTING
    • B41M5/00—Duplicating or marking methods; Sheet materials for use therein
    • B41M5/26—Thermography ; Marking by high energetic means, e.g. laser otherwise than by burning, and characterised by the material used
    • B41M5/36—Thermography ; Marking by high energetic means, e.g. laser otherwise than by burning, and characterised by the material used using a polymeric layer, which may be particulate and which is deformed or structurally changed with modification of its' properties, e.g. of its' optical hydrophobic-hydrophilic, solubility or permeability properties
    • B41M5/366—Thermography ; Marking by high energetic means, e.g. laser otherwise than by burning, and characterised by the material used using a polymeric layer, which may be particulate and which is deformed or structurally changed with modification of its' properties, e.g. of its' optical hydrophobic-hydrophilic, solubility or permeability properties using materials comprising a polymeric matrix containing a polymeric particulate material, e.g. hydrophobic heat coalescing particles

Definitions

  • the present invention relates to a method of preparing a negative-working printing plate precursor having a hydrophilic substrate and a heat-sensitive image-recording layer provided thereon as well as a method of making a printing plate using such a material.
  • Lithographic printing presses use a so-called printing master such as a printing plate which is mounted on a cylinder of the printing press.
  • the master carries a lithographic image on its surface and a print is obtained by applying ink to said image and then transferring the ink from the master onto a receiver material, which is typically paper.
  • ink as well as an aqueous fountain solution also called dampening liquid
  • the lithographic image which consists of oleophilic (or hydrophobic, i.e. ink-accepting, water-repelling) areas as well as hydrophilic (or oleophobic, i.e. water-accepting, ink-repelling) areas.
  • so-called driographic printing the lithographic image consists of ink-accepting and ink-abhesive (ink-repelling) areas and during driographic printing, only ink is supplied to the master.
  • Printing masters are generally obtained by the so-called computer-to-film method wherein various pre-press steps such as typeface selection, scanning, color separation, screening, trapping, layout and imposition are accomplished digitally and each color selection is transferred to graphic arts film using an image-setter.
  • the film can be used as a mask for the exposure of an imaging material called plate precursor and after plate processing, a printing plate is obtained which can be used as a master.
  • a typical printing plate precursor for computer-to-film methods comprise a hydrophilic support and an image-recording layer of a photosensitive polymer layers which include UV-sensitive diazo compounds, dichromate-sensitized hydrophilic colloids and a large variety of synthetic photopolymers. Particularly diazo-sensitized systems are widely used.
  • Upon image-wise exposure typically by means of a film mask in a UV contact frame, the exposed image areas become insoluble and the unexposed areas remain soluble in an aqueous alkaline developer.
  • the plate is then processed with the developer to remove the diazonium salt or diazo resin in the unexposed areas. So the exposed areas define the image areas (printing areas) of the printing master, and such printing plate precursors are therefore called 'negative-working'.
  • heat-sensitive printing plate precursors are known. Such materials offer the advantage of daylight stability and are especially used in the so-called computer-to-plate method wherein the plate precursor is directly exposed, i.e. without the use of a film mask.
  • the material is exposed to heat or to infrared light and the generated heat triggers a (physico-)chemical process, such as ablation, polymerization, insolubilization by cross-linking of a polymer, decomposition, or particle coagulation of a thermoplastic polymer latex.
  • a (physico-)chemical process such as ablation, polymerization, insolubilization by cross-linking of a polymer, decomposition, or particle coagulation of a thermoplastic polymer latex.
  • a daylight-stable material with high lithographic performance and typical prior art examples of such heat-sensitive materials will now be discussed.
  • thermoplastic polymer particles By image-wise exposure to an infrared laser, the thermoplastic polymer particles are image-wise coagulated thereby rendering the exposed areas ink-receptive without any further development.
  • EP-A-514145 discloses a heat-sensitive imaging element including a coating comprising core-shell particles having a water insoluble heat softenable core component and a shell component which is soluble or swellable in aqueous alkaline medium. Red or infrared laser light directed image-wise at said imaging element causes selected particles to coalesce, at least partially, to form an image and the non-coalesced particles are then selectively removed by means of an aqueous alkaline developer. Afterwards a baking step is performed.
  • EP-A-800928 discloses a heat sensitive imaging element comprising on a hydrophilic surface of a lithographic base an image forming layer comprising hydrophobic thermoplastic polymer particles dispersed in a water insoluble and alkali soluble or swellable resin and a compound capable of converting light into heat, wherein said alkali swellable or soluble resin comprises phenolic hydroxy groups and/or carboxyl groups.
  • EP 1 080 884 discloses a heat sensitive imaging element comprising on a hydrophilic surface of a lithographic base an image forming layer comprising hydrophobic thermoplastic polymer particles with a diameter between 0.2 ⁇ m and 1.4 ⁇ m and a compound capable of converting light into heat.
  • EP 0 881 096 discloses an imaging element comprising on a hydrophilic surface a barrier layer and a top layer comprising hydrophobic thermoplastic polymer particles and a compound capable of converting light into heat. Both layers are removable in an aqueous solution with a pH of at least 5.
  • EP 0 770 497 discloses a method for making a lithographic printing plate comprising the steps of image-wise exposing of a heat sensitive element comprising on a hydrophilic surface of a lithographic base an image forming layer comprising hydrophobic thermoplastic polymer particles dispersed in a hydrophilic binder and a compound capable of converting light into heat, and developing the imaging element by rinsing it with plain water or an aqueous liquid.
  • a method for obtaining a lithographic printing plate with improved ink-uptake comprising the steps of image-wise exposing, using a laser with a pixel dwell time between 0.1 ⁇ s and 50 ⁇ s, of a heat sensitive element comprising on a hydrophilic surface of a lithographic base an image forming layer comprising hydrophobic thermoplastic polymer particles dispersed in a hydrophilic binder and a compound capable of converting light into heat, and developing the imaging element.
  • EP 0 773 113 discloses a method for making a lithographic printing plate comprising the steps of (i) image-wise exposing of a heat sensitive element comprising on a hydrophilic surface of a lithographic base an image forming layer comprising hydrophobic thermoplastic polymer particles dispersed in a hydrophilic binder and a compound capable of converting light into heat and, (ii) developing the imaging element and (iii) overall heating the imaging element.
  • EP 0 773 112 discloses an imaging element comprising on a hydrophilic surface of a lithographic base an image forming layer comprising a hydrophobic thermoplastic polymer dispersed in a hydrophilic binder, a compound capable of converting light into heat and a cross-linking agent capable of cross-linking the hydrophilic binder upon heating.
  • This object is realized by the method defined in claim 1.
  • Specific features for preferred embodiments of the invention are set out in the dependent claims.
  • the use of a polymer B which has a softening temperature that is lower than the glass transition temperature of the hydrophobic thermoplastic particles of polymer A allows to heat the composition up to a temperature above the softening temperature of polymer B without substantially triggering the image mechanism of heat-induced fusing or coalescence of the particles of polymer A.
  • an aqueous dispersion of at least two polymers is prepared, referred to herein as polymer A and polymer B.
  • the glass transition temperature of polymer A is higher than the softening temperature of polymer B.
  • the softening temperature is the temperature at which the polymer begins to deform from a rigid state to a soft state, which normally occurs at a rapid rate over a narrow temperature interval.
  • the softening temperature is near the glass transition temperature, whereas for highly crystalline polymers it is close to the melting point.
  • the term "aqueous” shall be understood as meaning that more than 50 wt.% of the solvent is water.
  • Organic liquids which are miscible with water can be present, e.g. alcohols, ketones, or derivatives thereof, but preferably only water is used as a solvent.
  • Polymer A is a hydrophobic thermoplastic polymer that is not soluble or swellable in an aqueous alkaline developer.
  • suitable hydrophobic polymers are e.g. polyethylene, poly(vinyl chloride), poly(methyl (meth)acrylate), poly(ethyl (meth)acrylate), poly(vinylidene chloride), poly(meth)acrylonitrile, poly(vinyl carbazole), polystyrene or copolymers thereof.
  • Polystyrene and poly(meth)acrylonitrile or their derivatives are highly preferred embodiments of polymer A.
  • polymer A comprises at least 50 wt.% of polystyrene, and more preferably at least 65 wt.% of polystyrene.
  • polymer A preferably comprises at least 5 wt.%, more preferably at least 30 wt.% of nitrogen containing units or of units which correspond to monomers that are characterized by a solubility parameter larger than 20, such as (meth)acrylonitrile.
  • polymer A consists of styrene and acrylonitrile units in a weight ratio between 1:1 and 5:1 (styrene:acrylonitrile), e.g. in a 2:1 ratio.
  • the weight average molecular weight of the polymer A may range from 5,000 to 1,000,000 g/mol.
  • the hydrophobic particles of polymer A preferably have a number average particle diameter below 200 nm, more preferably between 10 and 100 nm.
  • the amount of hydrophobic thermoplastic polymer particles contained in the image-recording layer is preferably between 20% by weight and 65% by weight and more preferably between 25% by weight and 55% by weight and most preferably between 30% by weight and 45% by weight.
  • the particles of polymer A are present as a dispersion in an aqueous coating liquid of the image forming layer and may be prepared by the methods disclosed in US 3,476,937. Another method especially suitable for preparing an aqueous dispersion of the thermoplastic polymer particles comprises:
  • Polymer B is soluble or swellable in an aqueous alkaline developer but not soluble or swellable in water (i.e. at about neutral pH).
  • polymer B is also present as particles in the aqueous dispersion because the pH of the dispersion is not sufficiently high to cause dissolution of the particles of polymer B.
  • the polymer B comprises preferably a hydrophobic binder such as a phenolic resin, e.g. a novolac or resole resin, and/or a polymer containing a carboxy group, a sulfonamide group, a nitrile group, a maleimide group or a maleimidosulfadimidine group.
  • Polymer B preferably has a softening temperature below 100°C, more preferably below 75°C and most preferably below 50°C.
  • the weight ratio of the polymers A/B in the aqueous dispersion that is coated on the substrate is preferably larger than 0.5, more preferably larger than 0.6 and most preferably larger than 0.7.
  • the dispersion of polymer A and B that, according to the method of the present invention, is applied to the lithographic substrate, may also contain other ingredients such as additional binders, surfactants, colorants, development inhibitors or accelerators, and especially one or more compounds that are capable of converting infrared light into heat.
  • additional binders such as sodium carbides, borides, nitrides, carbonitrides, bronze-structured oxides, and conductive polymer dispersions such as polypyrrole, polyaniline or polythiophene-based conductive polymer dispersions.
  • the substrate used in the methods of the present invention has a hydrophilic surface.
  • the substrate may be a sheet-like material such as a plate or it may be a cylindrical element such as a sleeve which can be slid around a print cylinder of a printing press.
  • the substrate can also be the print cylinder itself.
  • the image-recording layer is provided on the print cylinder, e.g. by on-press spraying as described below.
  • the lithographic substrate may be a hydrophilic support or a support which is provided with a hydrophilic layer.
  • the support is a metal support such as aluminum or stainless steel.
  • a particularly preferred lithographic substrate is an electrochemically grained and anodized aluminum support.
  • the anodized aluminum support may be treated to improve the hydrophilic properties of its surface.
  • the aluminum support may be silicated by treating its surface with a 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, polyvinylsulfonic acid, polyvinylbenzenesulfonic acid, sulfuric acid esters of polyvinyl alcohol, and acetals of polyvinyl alcohols formed by reaction with a sulfonated aliphatic aldehyde It is further evident that one or more of these post treatments may be carried out alone or in combination.
  • the substrate can also be a flexible support, which is provided with a hydrophilic layer, hereinafter called 'base layer'.
  • the flexible support is e.g. paper, plastic film or aluminum.
  • plastic film are polyethylene terephthalate film, polyethylene naphthalate film, cellulose acetate film, polystyrene film, polycarbonate film, etc.
  • the plastic film support may be opaque or transparent.
  • the base layer is preferably a cross-linked hydrophilic layer obtained from a hydrophilic binder cross-linked with a hardening agent such as formaldehyde, glyoxal, polyisocyanate or a hydrolyzed tetra-alkylorthosilicate.
  • a hardening agent such as formaldehyde, glyoxal, polyisocyanate or a hydrolyzed tetra-alkylorthosilicate.
  • the thickness of the hydrophilic base layer may vary in the range of 0.2 to 25 ⁇ m and is preferably 1 to 10 ⁇ m.
  • the hydrophilic binder for use in the base layer is e.g. a hydrophilic (co)polymer such as homopolymers and copolymers of vinyl alcohol, acrylamide, methylol acrylamide, methylol methacrylamide, acrylate acid, methacrylate 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% by weight, preferably 80% by weight.
  • the amount of hardening agent, in particular tetraalkyl orthosilicate, is preferably at least 0.2 parts per part by weight of hydrophilic binder, more preferably between 0.5 and 5 parts by weight, most preferably between 1 parts and 3 parts by weight.
  • the hydrophilic base layer may also contain 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. 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.
  • the surface of the hydrophilic base layer is given a uniform rough texture consisting of microscopic hills and valleys, which serve as storage places for water in background areas.
  • hydrophilic base 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, and US-P- 4 284 705.
  • the amount of silica in the adhesion improving layer is between 200 mg/m 2 and 750 mg/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 /gram, more preferably at least 500 m 2 /gram.
  • the imaging layer can be applied on the lithographic substrate before or after mounting the substrate on the print cylinder of a printing press, unless the lithographic substrate is the print cylinder itself, as described above.
  • the dispersion is coated, sprayed or jetted on-press onto the substrate and exposed on-press by means of an integrated exposure apparatus.
  • the dispersion is coated on the substrate in an off-press apparatus and then mounted on the print cylinder.
  • the above compositions are also suitable for on-press cleaning after the press-run, e.g. by spraying or jetting a cleaning composition on the master, thereby removing the printing areas from the substrate which can then be reused in a next cycle of coating, exposing, printing and cleaning.
  • the image-recording layer After the image-recording layer has been applied on the substrate, it is heated to a temperature above the softening temperature of polymer B and preferably below the glass transition temperature of polymer A. Depending on the time and temperature of the heating step, it may result in a slight, a partial or complete fusing of the particles of polymer B which may lead to the formation of a film matrix wherein the particles of polymer A are dispersed.
  • the heating may be performed during the drying of the coated layer, or otherwise the drying may be carried out at a lower temperature, e.g. room temperature, and then the heating may be performed as a separate step after the drying.
  • the imaging materials used in the present invention are exposed to heat or to infrared light, e.g. by means of a thermal head, LEDs or an infrared laser.
  • a laser emitting near infrared light having a wavelength in the range from about 700 to about 1500 nm is used, e.g. a semiconductor laser diode, a Nd:YAG or a Nd:YLF laser.
  • the required laser power depends on the sensitivity of the image-recording layer, the pixel dwell time of the laser beam, which is determined by the spot diameter (typical value of modern plate-setters at 1/e 2 of maximum intensity : 10-25 ⁇ m), the scan speed and the resolution of the exposure apparatus (i.e.
  • ITD plate-setters for thermal plates are typically characterized by a very high scan speed up to 500 m s -1 and may require a laser power of several Watts.
  • the known plate-setters can be used as an off-press exposure apparatus in the present invention. This offers the benefit of reduced press down-time.
  • XTD plate-setter configurations can also be used for on-press exposure, offering the benefit of immediate registration in a multi-color press. More technical details of on-press exposure apparatuses are described in e.g. US 5,174,205 and US 5,163,368.
  • the particles of polymer A fuse or coagulate so as to form a hydrophobic phase which corresponds to the printing areas of the plate precursor. Coagulation may result from heat-induced coalescence, softening or melting of the thermoplastic polymer particles.
  • the coagulation temperature of the thermoplastic hydrophobic polymer particles there is no specific upper limit to the coagulation temperature of the thermoplastic hydrophobic polymer particles, however the temperature should be sufficiently below the decomposition of the polymer particles.
  • the coagulation temperature is at least 10°C below the temperature at which the decomposition of the polymer particles occurs.
  • the coagulation temperature is preferably higher than 50°C, more preferably above 100°C.
  • the non-exposed areas of the image-recording layer are removed by supplying an aqueous alkaline developer, which may be combined with mechanical,rubbing, e.g. by a rotating brush.
  • the development step may be followed by a drying step, a rinsing step and/or a gumming step.
  • the exposed and developed plates can be baked at a temperature of 230°C for 5 minutes, at a temperature of 150°C for 10 minutes or at a temperature of 120°C for 30 minutes.
  • 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 centre-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 sulphuric 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, post-treated 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.
  • High quality prints were obtained with the method according to the invention (1-4).
  • the coating was not completely removed from the substrate in the unexposed areas, resulting in toning during printing.
  • the coating was removed in both the exposed and the unexposed areas (no image).
  • Composition 7 was adjusted to a high pH, so that the novolac particles could dissolve in the coating solution. The material thereby obtained provided low quality prints with some ink uptake in the exposed areas.

Landscapes

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

Claims (10)

  1. Ein durch die nachstehenden Schritte gekennzeichnetes Verfahren zur Herstellung einer negativarbeitenden wärmeempfindlichen lithografischen Druckplattenvorstufe :
    (a) Anfertigung einer wässrigen Dispersion, enthaltend Teilchen eines hydrophoben thermoplastischen Polymers A, das nicht in einem wässrig-alkalischen Entwickler löslich oder quellbar ist, und Teilchen eines Polymers B, das in einem wässrig-alkalischen Entwickler löslich oder quellbar, jedoch nicht löslich oder quellbar in Wasser ist, wobei der Einfrierpunkt des Polymers A über der Erweichungstemperatur des Polymers B liegt,
    (b) Auftrag der wässrigen Dispersion auf ein lithografisches Substrat mit einer hydrophilen Oberfläche, wobei eine Bildaufzeichnungsschicht erhalten wird,
    (c) vollflächige Erwärmung der Bildaufzeichnungsschicht bei einer über der Erweichungstemperatur des Polymers B liegenden Temperatur, ohne jedoch dabei eine Koaleszierung der Teilchen des Polymers A auszulösen.
  2. Verfahren nach Anspruch 1, dadurch gekennzeichnet, dass die Bildaufzeichnungsschicht während Schritt (c) auf eine unter der Erweichungstemperatur des Polymers A liegende Temperatur erwärmt wird.
  3. Verfahren nach Anspruch 1, dadurch gekennzeichnet, dass die Bildaufzeichnungsschicht während Schritt (c) auf eine unter dem Einfrierpunkt des Polymers A liegende Temperatur erwärmt wird.
  4. Verfahren nach einem der vorstehenden Ansprüche, dadurch gekennzeichnet, dass die Teilchen des Polymers B ein Phenolharz und/oder ein eine Carboxylgruppe, eine Sulfonamidgruppe, eine Nitrilgruppe, eine Maleimidgruppe oder eine Maleimidsulfadimidingruppe enthaltendes Polymer sind.
  5. Verfahren nach einem der vorstehenden Ansprüche, dadurch gekennzeichnet, dass das Gewichtsverhältnis der Polymere A/B mehr als 0,5 beträgt.
  6. Verfahren nach einem der vorstehenden Ansprüche, dadurch gekennzeichnet, dass Polymer A zumindest 5% Einheiten mit einem Löslichkeitsparameter von mehr als 20 enthält.
  7. Verfahren nach einem der vorstehenden Ansprüche, dadurch gekennzeichnet, dass Polymer A zumindest 5% (Meth)acrylnitryleinheiten enthält.
  8. Verfahren nach einem der vorstehenden Ansprüche, dadurch gekennzeichnet, dass die Teilchen des Polymers A ein Zahlenmittel des Teilchendurchmessers von weniger als 200 nm aufweisen.
  9. Ein durch die nachstehenden Schritte gekennzeichnetes Verfahren zur Herstellung einer lithografischen Druckplatte :
    bildmäßige Erwärmung oder Belichtung mit Infrarotlicht einer lithografischen Druckplattenvorstufe, die nach einem Verfahren nach einem der vorstehenden Ansprüche erhalten ist, und
    Entfernung der nicht-belichteten Bereiche der Bildaufzeichnungsschicht mit einer wässrig-alkalischen Lösung.
  10. Verfahren zur Herstellung einer lithografischen Druckplatte nach Anspruch 9, das ferner den Schritt umfasst, in dem die Druckplatte bei einer über dem Einfrierpunkt des Polymers A liegenden Temperatur eingebrannt wird.
EP20020100128 2001-03-20 2002-02-12 Verfahren zur Herstellung einer negativarbeitenden, wärmeempfindlichen, lithographischen Druckplattenvorstufe Expired - Lifetime EP1243413B1 (de)

Priority Applications (1)

Application Number Priority Date Filing Date Title
EP20020100128 EP1243413B1 (de) 2001-03-20 2002-02-12 Verfahren zur Herstellung einer negativarbeitenden, wärmeempfindlichen, lithographischen Druckplattenvorstufe

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
EP01000059 2001-03-20
EP01000059A EP1243410A1 (de) 2001-03-20 2001-03-20 Verfahren zur Herstellung eines wärmeempfindlichen Vorläufers für eine Flachdruckplatte
EP20020100128 EP1243413B1 (de) 2001-03-20 2002-02-12 Verfahren zur Herstellung einer negativarbeitenden, wärmeempfindlichen, lithographischen Druckplattenvorstufe

Publications (2)

Publication Number Publication Date
EP1243413A1 EP1243413A1 (de) 2002-09-25
EP1243413B1 true EP1243413B1 (de) 2004-05-26

Family

ID=26076405

Family Applications (1)

Application Number Title Priority Date Filing Date
EP20020100128 Expired - Lifetime EP1243413B1 (de) 2001-03-20 2002-02-12 Verfahren zur Herstellung einer negativarbeitenden, wärmeempfindlichen, lithographischen Druckplattenvorstufe

Country Status (1)

Country Link
EP (1) EP1243413B1 (de)

Families Citing this family (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20050153239A1 (en) * 2004-01-09 2005-07-14 Fuji Photo Film Co., Ltd. Lithographic printing plate precursor and lithographic printing method using the same
US7348126B2 (en) 2004-04-27 2008-03-25 Agfa Graphics N.V. Negative working, heat-sensitive lithographic printing plate precursor
US7354696B2 (en) 2004-07-08 2008-04-08 Agfa Graphics Nv Method for making a lithographic printing plate
US7425405B2 (en) 2004-07-08 2008-09-16 Agfa Graphics, N.V. Method for making a lithographic printing plate
US7195861B2 (en) 2004-07-08 2007-03-27 Agfa-Gevaert Method for making a negative working, heat-sensitive lithographic printing plate precursor
ATE434518T1 (de) 2005-06-17 2009-07-15 Agfa Graphics Nv Verfahren zur herstellung eines negativ arbeitenden lithographischen druckplattenvorläufers
ATE402012T1 (de) * 2005-09-27 2008-08-15 Agfa Graphics Nv Verfahren zur herstellung einer lithographischen druckplatte
EP3121008B1 (de) * 2015-07-23 2018-06-13 Agfa Nv Lithografiedruckplattenvorläufer mit graphitoxid
WO2019039074A1 (ja) * 2017-08-25 2019-02-28 富士フイルム株式会社 ネガ型平版印刷版原版、及び、平版印刷版の製版方法

Family Cites Families (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1084070A (en) 1960-08-05 1967-09-20 Kalle Ag Process and material for the preparation of planographic printing plates
DE3717654A1 (de) 1987-05-26 1988-12-08 Hoechst Ag Verfahren zur elektrochemischen aufrauhung von aluminium fuer druckplattentraeger
DE4001466A1 (de) 1990-01-19 1991-07-25 Hoechst Ag Verfahren zur elektrochemischen aufrauhung von aluminium fuer druckplattentraeger
GB9110417D0 (en) 1991-05-14 1991-07-03 Du Pont Howson Ltd Improvements in or relating to the formation of images
DE4134143A1 (de) 1991-10-16 1993-06-24 Hoechst Ag Verfahren zur herstellung von flachdruckformen und danach hergestellte flachdruckformen
GB9326150D0 (en) 1993-12-22 1994-02-23 Alcan Int Ltd Electrochemical roughening method
DE4417907A1 (de) 1994-05-21 1995-11-23 Hoechst Ag Verfahren zur Nachbehandlung von platten-, folien- oder bandförmigem Material, Träger aus derartigem Material und seine Verwendung für Offsetdruckplatten
DE4423140A1 (de) 1994-07-01 1996-01-04 Hoechst Ag Hydrophiliertes Trägermaterial und damit hergestelltes Aufzeichnungsmaterial
EP1092555B1 (de) * 1995-10-24 2002-08-21 Agfa-Gevaert Verfahren zur Herstellung einer lithographischen Druckplatte mit auf der Druckpresse stattfindender Entwicklung
EP0773112B1 (de) * 1995-11-09 2001-05-30 Agfa-Gevaert N.V. Wärmeempfindliches Aufzeichnungselement und Verfahren zur Herstellung einer Druckform damit
EP0773113B1 (de) * 1995-11-09 2000-05-24 Agfa-Gevaert N.V. Wärmeempfindliches Aufzeichnungselement und Verfahren zur Herstellung einer lithographischen Druckform damit
EP0839647B2 (de) * 1996-10-29 2014-01-22 Agfa Graphics N.V. Verfahren zur Herstellung einer lithographischen Druckplatte mit verbesserten Druckfarbe-Aufnahme
EP0881096B1 (de) * 1997-05-27 2001-10-17 Agfa-Gevaert N.V. Wärmempfindliches Aufzeichnungselement und Verfahren zur Herstellung von Flachdruckplatten damit
DE69912771T2 (de) * 1999-08-31 2004-09-23 Agfa-Gevaert Verarbeitungsfreie thermische Flackdruckplatte mit einer genau definierten Nanostruktur

Also Published As

Publication number Publication date
EP1243413A1 (de) 2002-09-25

Similar Documents

Publication Publication Date Title
US6641976B2 (en) Method of making a negative-working heat-sensitive lithographic printing plate precursor
EP1356926B1 (de) Negativ-arbeitender thermischer Flachdruckplattenvorläufer, der einen Aluminiumträger mit einer glatten Oberfläche enthält
US7195861B2 (en) Method for making a negative working, heat-sensitive lithographic printing plate precursor
EP1916101B1 (de) Verfahren zum Nacheinbrennen lithographischer Druckplatten
EP1614539A1 (de) Verfahren zur Herstellung einer lithographischen Druckplatte
EP1614538A2 (de) Verfahren zur Herstellung einer negativarbeitenden, wärmeempfindlichen, lithographischen Druckplattenvorstufe
EP1614540A1 (de) Verfahren zur Herstellung einer lithographischen Druckplatte
EP1594696B1 (de) Wärmeempfindlicher lithographischer druckplattenvorläufer
US6983694B2 (en) Negative-working thermal lithographic printing plate precursor comprising a smooth aluminum support
EP1243413B1 (de) Verfahren zur Herstellung einer negativarbeitenden, wärmeempfindlichen, lithographischen Druckplattenvorstufe
EP1974911B1 (de) Verfahren zur Herstellung einer Flachdruckplatte
US7425405B2 (en) Method for making a lithographic printing plate
US7354696B2 (en) Method for making a lithographic printing plate
EP1080884B1 (de) Verarbeitungsfreie thermische Flackdruckplatte mit einer genau definierten Nanostruktur
EP1738900B1 (de) Wärmeempfindlicher Flachdruckplattenvorläufer
US20050037287A1 (en) Method for postbaking a lithographic printing plate
US6846613B2 (en) Positive-working lithographic printing plate precursors
EP1256444B1 (de) Positivarbeitende lithographische Druckplattenvorläufer
EP1243410A1 (de) Verfahren zur Herstellung eines wärmeempfindlichen Vorläufers für eine Flachdruckplatte
EP1249341A1 (de) Flachdruckplattenvorläufer
EP1243411B1 (de) Tintenstrahlbeschichtungsverfahren für eine Bildaufzeichnungsschicht
US7294447B2 (en) Positive-working lithographic printing plate precursor
US6820552B2 (en) Cleaning method for recycling a printing substrate by laser ablation
EP1295717B1 (de) Wärmeempfindlicher positiv arbeitender Flachdruckplattenvorläufer
EP1232877B1 (de) Reinigungsverfahren zur Wiederverwendung eines Druckträgers durch Laserablation

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): AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE TR

AX Request for extension of the european patent

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

17P Request for examination filed

Effective date: 20030325

AKX Designation fees paid

Designated state(s): DE FR GB

17Q First examination report despatched

Effective date: 20030624

GRAP Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOSNIGR1

GRAS Grant fee paid

Free format text: ORIGINAL CODE: EPIDOSNIGR3

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

RIN1 Information on inventor provided before grant (corrected)

Inventor name: VAN DAMME, MARC

Inventor name: VERMEERSCH, JOAN

AK Designated contracting states

Kind code of ref document: B1

Designated state(s): DE FR GB

REG Reference to a national code

Ref country code: GB

Ref legal event code: FG4D

REG Reference to a national code

Ref country code: IE

Ref legal event code: FG4D

REF Corresponds to:

Ref document number: 60200521

Country of ref document: DE

Date of ref document: 20040701

Kind code of ref document: P

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

Effective date: 20050301

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

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

Ref country code: GB

Payment date: 20101216

Year of fee payment: 10

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

Ref country code: FR

Payment date: 20111220

Year of fee payment: 11

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

Ref country code: DE

Payment date: 20111214

Year of fee payment: 11

GBPC Gb: european patent ceased through non-payment of renewal fee

Effective date: 20130212

REG Reference to a national code

Ref country code: FR

Ref legal event code: ST

Effective date: 20131031

REG Reference to a national code

Ref country code: DE

Ref legal event code: R119

Ref document number: 60200521

Country of ref document: DE

Effective date: 20130903

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 NON-PAYMENT OF DUE FEES

Effective date: 20130212

Ref country code: DE

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20130903

Ref country code: FR

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20130228