Classifications

• • G—PHYSICS
  • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
  • G03F—PHOTOMECHANICAL PRODUCTION OF TEXTURED OR PATTERNED SURFACES, e.g. FOR PRINTING, FOR PROCESSING OF SEMICONDUCTOR DEVICES; MATERIALS THEREFOR; ORIGINALS THEREFOR; APPARATUS SPECIALLY ADAPTED THEREFOR
  • G03F5/00—Screening processes; Screens therefor
  • G03F5/20—Screening processes; Screens therefor using screens for gravure printing
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
  • B41M—PRINTING, DUPLICATING, MARKING, OR COPYING PROCESSES; COLOUR PRINTING
  • B41M3/00—Printing processes to produce particular kinds of printed work, e.g. patterns
  • B41M3/06—Veined printings; Fluorescent printings; Stereoscopic images; Imitated patterns, e.g. tissues, textiles
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
  • B41M—PRINTING, DUPLICATING, MARKING, OR COPYING PROCESSES; COLOUR PRINTING
  • B41M7/00—After-treatment of prints, e.g. heating, irradiating, setting of the ink, protection of the printed stock
  • B41M7/0045—After-treatment of prints, e.g. heating, irradiating, setting of the ink, protection of the printed stock using protective coatings or film forming compositions cured by mechanical wave energy, e.g. ultrasonics, cured by electromagnetic radiation or waves, e.g. ultraviolet radiation, electron beams, or cured by magnetic or electric fields, e.g. electric discharge, plasma
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
  • B41M—PRINTING, DUPLICATING, MARKING, OR COPYING PROCESSES; COLOUR PRINTING
  • B41M7/00—After-treatment of prints, e.g. heating, irradiating, setting of the ink, protection of the printed stock
  • B41M7/0054—After-treatment of prints, e.g. heating, irradiating, setting of the ink, protection of the printed stock using protective coatings or film forming compositions cured by thermal means, e.g. infrared radiation, heat
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
  • B41M—PRINTING, DUPLICATING, MARKING, OR COPYING PROCESSES; COLOUR PRINTING
  • B41M7/00—After-treatment of prints, e.g. heating, irradiating, setting of the ink, protection of the printed stock
  • B41M7/0081—After-treatment of prints, e.g. heating, irradiating, setting of the ink, protection of the printed stock using electromagnetic radiation or waves, e.g. ultraviolet radiation, electron beams

Definitions

• the invention pertains to a printing process for obtaining relief or embossing effects .
• Embossing technology requires embossing cylinders comprising the desired patterns to be embossed on the printable medium. Embossing cylinders consist of 2 parts
• embossing technology cost, since embossing cylinders are much more expensive than printing cylinders .
• Silkscreen printing involves applying foaming ink on a printable medium.
• the main drawbacks of silkscreen printing include increased time for letting the foaming ink to rise, additional equipment such as printing units and powerful ovens for the drying process, fuzzy rendering of images and reduced durability of printing tools . Further, the line speed is reduced .
• the present invention provides a printing process for obtaining relief effects on a printable medium, said printing process comprising the following steps : a . applying a layer of a UV-activable product (i . e . product whose polymerisation is triggered by application of ultraviolet light) on a printing tool, the surface of said printing tool having engraved, direct lasered or etched cells containing said UV- activable product and forming desired patterns; b . applying said printing tool onto said printable medium; c . applying ultraviolet light to said printable medium comprising said UV-activable product .
• a UV-activable product i . e . product whose polymerisation is triggered by application of ultraviolet light
• Said UV-activable product may be UV-activable ink, UV- activable varnish or any other UV-activable product .
• said UV-activable product may be based on a cationic UV-activable system or a radical UV-activable system.
• said UV-activable product has a solids content of at least 90% and a viscosity rating between 35 and 100 seconds (viscosity rating measured according to the 4 mm DIN cup method) .
• the printing tool according to the invention may be a printing cylinder, a printing plate or any other printing tool .
• the printing process according to the invention is preferably gravure printing, but may also consist in any- other printing techniques such as offset printing, etc .
• the process of the invention is preferably used on foil, semi-rigid packaging material and rigid packaging material as printable medium, but may also be used with any other appropriate printable medium.
• the process according to the invention is used for printing cigarette packs , where relief effects help differentiating the packaging from competition .
• the present invention consists in the application of a special varnish at a high layer thickness using existing gravure technique to imitate embossing .
• a varnish will be applied on the board online with gravure technique using a gravure cylinder without compromising on production speed.
• the layer thickness needs to be increased significantly, e . g . to a range of 60-100 micron .
• Such thickness requires special ink type, e . g . - High reactivity varnish to promote fast curing/polymerisation of the thick layer .
• High solids content ideally 100%, to avoid reduction of the height of the relief during cure and to avoid long drying time due to solvent evaporation.
• a radical UV-varnish is ideal as it fulfils the above requirements .
• Cross-linking/polymerisation is initiated via UV-light .
• the initiation of the polymerisation is also conceivable via heat or other physico-chemical means .
• Viscosity 35-100 sec (measured according to the 4 mm DIN cup method) solid contents : preferably 90 to 100% reactivity: immediate drying Gravure cylinder :
• Gravure cylinders for applying UV-varnish are considerably cheaper (one order of magnitude) compared to embossing cylinders .
• High gloss is obtained without an extra printing step .
• One application of UV-varnish may be used to attain both relief printing and high gloss .
• embossing technology an extra layer of high gloss varnish is required.

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• Physics & Mathematics (AREA)
• Health & Medical Sciences (AREA)
• Engineering & Computer Science (AREA)
• Electromagnetism (AREA)
• General Health & Medical Sciences (AREA)
• Mechanical Engineering (AREA)
• Plasma & Fusion (AREA)
• Toxicology (AREA)
• General Physics & Mathematics (AREA)
• Textile Engineering (AREA)
• Vascular Medicine (AREA)
• Printing Methods (AREA)
• Cash Registers Or Receiving Machines (AREA)

Applications Claiming Priority (2)

Publications (1)

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Family Cites Families (13)

• 2005
  • 2005-12-23 EP EP05821710A patent/EP1834214A2/de not_active Withdrawn
  • 2005-12-23 WO PCT/IB2005/003876 patent/WO2006072824A2/en active Application Filing

Non-Patent Citations (1)

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