Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
  • B41F—PRINTING MACHINES OR PRESSES
  • B41F27/00—Devices for attaching printing elements or formes to supports
  • B41F27/12—Devices for attaching printing elements or formes to supports for attaching flexible printing formes
  • B41F27/1262—Devices for attaching printing elements or formes to supports for attaching flexible printing formes without tensioning means
  • B41F27/1275—Devices for attaching printing elements or formes to supports for attaching flexible printing formes without tensioning means by means of adhesives, staples
• • 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
  • B41N6/00—Mounting boards; Sleeves Make-ready devices, e.g. underlays, overlays; Attaching by chemical means, e.g. vulcanising
  • B41N6/02—Chemical means for fastening printing formes on mounting boards

Definitions

• the invention relates to a method and a device for carrying out the method for fastening a flexible, thin printing plate on a plate cylinder of a rotary printing press.
• Thin printing plates in particular have only a low intrinsic stiffness, so that they can be displaced, in particular laterally, on the plate cylinder by forces acting on them.
• a shift of the printing plate can cause register errors and thus cause a reduction in quality.
• the pressure plate can be damaged.
• the invention has for its object to provide a method and an apparatus for performing the method for fastening a flexible, thin printing plate on a plate cylinder of a rotary printing press, which enables transverse forces to be absorbed by the printing plate and which allows the printing plate can be detached from the plate cylinder quickly and non-destructively.
• the method and the device according to the invention have a number of advantages. Even when using conventional printing plate clamping devices, the flexible, thin printing plate rests firmly and immovably on the plate cylinder. This creates almost distortion-free images of high quality on the print carrier.
• the new method advantageously makes it possible to save conventional printing plate clamping devices and u. U. also the saving of the printing plate clamping device, so that only devices for register-correct application of the printing plate are required.
• Register devices can be of the simplest type, starting from very narrow register slots, into which a printing plate start is hung, to simple markings on the surface of the plate cylinder, which are brought into line with the thin, flexible printing plate.
• Plate cylinders of such a simple design can be produced very inexpensively and at the same time enable printing with very narrow wheels. Although the thin, flexible printing plates adhere to the plate cylinder so that they cannot move, they can be easily removed from the plate cylinder without destruction and are therefore reusable.
• the printing plates used in the method according to the invention are thin, flexible plastic printing plates (0.1-0.5 mm) z. B. from polyester or metal foils. This for both direct and indirect high pressure as well as offset / planographic printing plates are provided on the back with a layer of adhesive for detachable connections.
• adhesives There are currently z. B. the following such adhesives available, Scotch 3M "spray adhesive", Anchorit “spray adhesive” or harrows "assembly adhesive”.
• the leading edge of the printing plate is placed against the plate cylinder and aligned with register marks.
• the printing plate is then placed wrinkle-free on the surface of the plate cylinder. This is done by smoothing the pressure plate by hand or another means, e.g. B. also by the contact pressure of another cylinder interacting with the plate cylinder (rubber cylinder, impression cylinder, pressure roller etc.).
• the printing plate adheres firmly to the surface of the plate cylinder.
• a coefficient of friction eg ⁇ > 50
• the surface of the plate cylinder can be permanently covered with a flexible underlay. This usually consists of a fine-pored foam (micro cells).
• the thin, flexible printing plate is then releasably attached to the base by means of the adhesive. To release the printing plate from the plate cylinder, it is first lifted from the cylinder at its front or rear edge (e.g. by hand) and is then raised continuously from the respective first lifting point.
• the plate cylinder has an axially parallel, flat, V-shaped pit.
• Register pins are provided in the inclined side walls, via which a beginning of the printing plate is hung in register.
• One end of the pressure plate lies unsecured on the surface of the plate cylinder.
• the V-shaped pit for receiving the register device is suitable for both directions of rotation. If the direction of rotation of the plate cylinder is changed, the pressure plate is released and its start of pressure is attached to the register pins on the other side wall of the V-shaped pit.
• a cylinder-long, Axially parallel slot in which a pressure plate beginning which is bent in register is hung.
• the bent printing plate end is also hooked into the slot or remains un-folded on the surface of the plate cylinder due to the adhesive force of the adhesive.
• This version is also suitable for reversing the direction of rotation of the plate cylinder.
• an insert is provided for the v-shaped pit and the slot, which also closes the pit or slot at the same time.
• the plate cylinder now has an all-round closed surface.
• the thin, flexible pressure plate now only lies on the surface of the plate cylinder by the adhesive force of the adhesive for detachable connections.
• this has markings that are required for the correct application of the printing plate.
• the register marks are only brought into line with corresponding markings on the printing plate. In the case of transparent plastic plates, these register markings can, for. B. painted or printed on the printing plate. In the case of metal foils, the register marks can e.g. B. be punched out so that they can be brought into register with the corresponding register marks on the plate cylinder.
• the invention is not only applicable to thin, flexible printing plates, but also to all of them other possible detachable connections between cylinders and their elevators.
• the principle of the invention is therefore that an adhesive is applied between the support surface of a cylinder and the back of a thin, flexible printing plate or other thin, flexible elevator, which creates a releasable connection between the two bodies.
• the cylinder has a coating or another non-releasable base
• the releasable connection of the pressure plate or the base with the cylinder coating or the non-releasably attached base is made.
• the adhesive is not limited to the specified glue alone. It is also conceivable liability z. B. by means of electrostatic charging.

Landscapes

• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Chemical & Material Sciences (AREA)
• Chemical Kinetics & Catalysis (AREA)
• General Chemical & Material Sciences (AREA)
• Supply, Installation And Extraction Of Printed Sheets Or Plates (AREA)
• Discharge By Other Means (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=6403068

Family Applications (1)

Country Status (4)

Cited By (6)

Families Citing this family (1)

Citations (6)

• 1990
  • 1990-03-26 DE DE19904009649 patent/DE4009649A1/de not_active Withdrawn
• 1991
  • 1991-03-22 EP EP91104523A patent/EP0449131A1/fr not_active Withdrawn
  • 1991-03-22 JP JP5870591A patent/JPH04221639A/ja active Pending
  • 1991-03-25 RU SU4894917 patent/RU1814621C/ru active

Patent Citations (6)

Non-Patent Citations (1)

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