Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
  • B41N—PRINTING PLATES OR FOILS; MATERIALS FOR SURFACES USED IN PRINTING MACHINES FOR PRINTING, INKING, DAMPING, OR THE LIKE; PREPARING SUCH SURFACES FOR USE AND CONSERVING THEM
  • B41N10/00—Blankets or like coverings; Coverings for wipers for intaglio printing
  • B41N10/02—Blanket structure
  • B41N10/04—Blanket structure multi-layer
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
  • B41N—PRINTING PLATES OR FOILS; MATERIALS FOR SURFACES USED IN PRINTING MACHINES FOR PRINTING, INKING, DAMPING, OR THE LIKE; PREPARING SUCH SURFACES FOR USE AND CONSERVING THEM
  • B41N2210/00—Location or type of the layers in multi-layer blankets or like coverings
  • B41N2210/04—Intermediate layers
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
  • B41N—PRINTING PLATES OR FOILS; MATERIALS FOR SURFACES USED IN PRINTING MACHINES FOR PRINTING, INKING, DAMPING, OR THE LIKE; PREPARING SUCH SURFACES FOR USE AND CONSERVING THEM
  • B41N2210/00—Location or type of the layers in multi-layer blankets or like coverings
  • B41N2210/12—Location or type of the layers in multi-layer blankets or like coverings characterised by non-macromolecular organic compounds
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
  • B41N—PRINTING PLATES OR FOILS; MATERIALS FOR SURFACES USED IN PRINTING MACHINES FOR PRINTING, INKING, DAMPING, OR THE LIKE; PREPARING SUCH SURFACES FOR USE AND CONSERVING THEM
  • B41N2210/00—Location or type of the layers in multi-layer blankets or like coverings
  • B41N2210/14—Location or type of the layers in multi-layer blankets or like coverings characterised by macromolecular organic compounds

Definitions

• the invention relates to a method for producing printing blankets for offset printing by applying a layer made of a porous, elastic material to a carrier layer consisting of fiber material.
• the upper carrier consists of paper as the carrier material, on which a spread is applied, which corresponds in its composition to the rubber blankets previously used.
• a rubber filled with carbon black has preferably been used for this, because the carbon black improves the oleo- and hydrophilic wetting ability of the rubber to a desired extent.
• a perfect print quality could only be achieved with film-like top carriers when using paper with the best surface properties.
• a layer product is used as the upper carrier, which consists of a dimensionally stable carrier material and a layer of unfilled latex applied thereon, the optimal color transfer behavior of which is set via the degree of crosslinking .
• the wetting ability of this transfer agent is increased by incorporating carboxyl groups and by adding oleophilic substances.
• a printing blanket with a printing surface which has a compressible layer of a cellular elastic polymer, the cells of which are formed by hollow microspheres.
• a method for producing printing blankets for offset printing by applying a layer made of a porous, elastic material to a carrier layer consisting of fiber material. Thereafter, a plastisol-containing polyvinyl chloride-based propellant containing a blowing agent is applied to the carrier layer consisting of fiber material in a uniform layer thickness, expanded at elevated temperature and formed into a porous layer, whereupon a thin spread is applied to the free surface of the porous layer, which has the disadvantageous effect Effect of in the porous layer contained plasticizer on the free surface of the porous layer on the reproduction of the printed image prevented.
• a product consisting of fiber material, such as a tear-resistant paper with a basis weight of 140 g / m 2 and a tear length of at least 3000 to 4000 m, is used as the carrier layer.
• Nonwoven fabrics are also suitable for this purpose.
• this plastisol is advantageously applied in an amount of 130 to 200 g / m 2 continuously to the carrier layer.
• the coating product thus obtained is then subjected, under simultaneous expansion, to conditions under which the plastisol gels out.
• the coating product is advantageously brought to a temperature by selective heat radiation or in a gelling channel at which the plastisol layer loses in a technically acceptable time without the carrier material being attacked in the process.
• a gelling channel of 8 to 20 m in length the plastisol layer expands and gels out when the layer material is conveyed through the gelling channel at a speed of 20 to 30 m / min, in which a temperature of 180 to 200 ° C. is maintained.
• a layered product After cooling, a layered product is obtained whose foamed layer with a density of 0.4 to 0.8 consists of foam which is as fine-pored as possible and which has a closed surface.
• this product which is already suitable as a printing blanket, produces fuzzy print images, especially on the first prints.
• the cause is a plasticizer veil which, at the temperatures to be maintained in the gelling channel, forms as condensate on the free surface of the foamed layer.
• This disadvantage is eliminated in that a thin spread is applied to the free surface of the porous layer, which cancels out the disadvantageous effect of this plasticizer veil on the print quality, especially the first prints, and ensures perfect reproduction of the printed image.
• a spread of 5 to 10 parts by weight of polymethyl methacrylate with a density of 1.12 to 1.17, 10 to 5 parts by weight of polyvinyl chloride with a k value of 40 to 50, about 80 parts by weight has proven useful for this.
• This spread agent can be diluted by addition of further amounts of solvent to a favorable for the application viscosity.
• the amount of the spreading agent to be used should be such that it corresponds to a solids application of 4 to 8 g / m 2.
• the solvents used should be inert with respect to the porous layer.
• the spread can advantageously be applied with a gravure printing machine with a full-surface gravure cylinder inserted This enables painting speeds of 80 to 120 m / min to be achieved Lacquered product dried at a temperature of about 80 ° C.
• the final spread on the free surface of the porous layer not only prevents the damaging influence of the plasticizer condensed on this surface, but also forms a non-porous and even printing surface.
• the impressions produced with a printing blanket produced according to the invention are of the best quality and sharpness from the first to the ten thousandth and far above.

Landscapes

• Laminated Bodies (AREA)
• Printing Plates And Materials Therefor (AREA)
• Paper (AREA)

Applications Claiming Priority (2)

Publications (2)

Family

ID=6048399

Family Applications (1)

Country Status (2)

Cited By (2)

Citations (7)

Family Cites Families (3)

• 1978
  • 1978-08-31 DE DE19782838069 patent/DE2838069C2/de not_active Expired
• 1979
  • 1979-08-27 EP EP79103151A patent/EP0008760A3/fr not_active Withdrawn

Patent Citations (7)

Also Published As

Similar Documents

Legal Events