Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
  • B65H—HANDLING THIN OR FILAMENTARY MATERIAL, e.g. SHEETS, WEBS, CABLES
  • B65H39/00—Associating, collating, or gathering articles or webs
  • B65H39/16—Associating two or more webs
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
  • B41F—PRINTING MACHINES OR PRESSES
  • B41F15/00—Screen printers
  • B41F15/14—Details
  • B41F15/16—Printing tables
  • B41F15/18—Supports for workpieces
  • B41F15/24—Supports for workpieces for webs
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
  • B41M—PRINTING, DUPLICATING, MARKING, OR COPYING PROCESSES; COLOUR PRINTING
  • B41M1/00—Inking and printing with a printer's forme
  • B41M1/12—Stencil printing; Silk-screen printing

Definitions

• the invention relates to a method for printing a substrate in a continuous or discontinuous printing method, in particular screen printing method, the substrate being placed on a printing pad and affixed thereon for printing with the aid of an adhesive, and then again from the same is solved.
• Substrates for example web-shaped textiles, paper or plastic films, can be printed by known continuous or discontinuous printing processes, for example by the screen printing process.
• the substrate, especially the textile substrate is glued for the actual printing process with an endless carrier tape of the printing blanket serving as the printing substrate, in order to rule out shifting of the substrate to be printed on by contact with the printing form and dimensional changes due to the printed printing ink, and thus a precise registration Ensure printing with more than one printing form.
• the adhesion of the substrate The type and amount of the adhesive and auxiliary devices are used to set the print substrate in such a way that unwanted substrate movement during printing is avoided due to the influences mentioned, but on the other hand a substrate-appropriate, mechanical detachment of the printed substrate from the print substrate is ensured.
• a thin, aqueous layer of glue is applied by a suitable device, e.g. by roller or knife application, applied to the printing blanket, onto which the substrate to be printed is then mechanically pressed.
• thermoplastic adhesives The aforementioned reservation effect occurring when using such glues can be avoided in a known manner by thermoplastic adhesives.
• the printing tape is coated and dried in a previous operation with a resin layer, e.g. consisting of a solution of a copolymer of an acrylic acid ester and a copolymer of vinyl chloride and vinyl propionate in an organic solvent, such as ethyl acetate
• the resin layer is heated using, for example, JR emitters, and the substrate web to be printed is then pressed onto the layer.
• the thermoplasticity of the resin layer causes a softening that can be controlled depending on the heating power, as a result of which the desired bonding to the substrate is achieved.
• thermoplastic adhesives Although with the known thermoplastic adhesives the user has a working medium which largely corresponds to his needs, apart from the fact that the solvents which may be used in this case pose occupational hygiene and ecological problems, associated with a latent risk of explosion, the control of which does not, however represents insurmountable obstacles - expressed further requests for improvement, which relate to the duration of use of the adhesive layers and are connected with the conditions of application and removal of the resin covering given in the use of the adhesive.
• thermoplastic resin layer is in constant contact during use, ie during printing, both with the substrate to be printed, generally textiles of all kinds, and with the printing inks. Fiber residues as well as residues of auxiliary chemicals and dyes from the printing ink remain on the resin layer, because the printing tape cleaning cannot be designed so effectively in machine practice that any foreign substance residue is removed from the sticky resin surface. For this reason, more and more non-adhesive particles of substrate and printing ink accumulate on the resin surface over time, which leads to a permanent decrease in the stickiness. Depending on the condition, after 50,000-500,000 printing meters there comes the point at which the thermoplastic covering no longer sticks. As a rule, the printing blanket is then washed with organic solvents and provided with a new coating.
• Washing is particularly unfavorable with regard to labor, hygiene and environmental pollution, and is also dangerous since not inconsiderable amounts of solvent have to be used, for example 40-60 liters of acetone or trichlorethylene for about 45 m 2 of printing blanket is covered with 20 - 200 gr / m2 resin.
• the new order offers fewer disadvantages in this respect, but because of the drying conditions to be observed it is inevitable a process that takes several hours and thus reduces machine use.
• the invention is therefore based on the object of designing a method of the type described at the outset in such a way that the adhesive bonded to the printing tape, i.e. the adhesive layer can be renewed with little effort, ecologically acceptable and harmless, without having to forego the application-related advantages of the thermoplastic.
• Substrate temporarily attached a film and this is coated with the adhesive.
• the invention provides a printing blanket which consists of a printing base and a film temporarily attached to it, which in turn is covered with a thermoplastic see resin layer as an adhesive for the substrate is coated.
• FIG. 1 shows a schematic view of the inlet-side part of a rotary printing machine
• FIG. 2 shows a detail on an enlarged scale of the printing blanket according to the invention.
• a printing tape or a printing blanket 1 is shown, which rotates over two deflecting rollers 2, only one of which is shown.
• a press roll 3 is arranged on the entry side into the printing section and cooperates with a support roll 4.
• a film 6 is pulled off a brakeable shaft 5.
• the film 6 is expediently made of a plastic, e.g. Polyester.
• the film 6 is coated on both sides, namely on one side with an adhesive or adhesive layer 10 and on the other side with a thermoplastic resin layer 11.
• this film 6 provided with the thermoplastic resin layer 11 ' is fastened on the printing blanket 1 in such a way that the thermoplastic covering lies on the free side, ie touches the substrate to be printed.
• the film 6 pulled off the shaft 5 is spread out by a curved roller 7 and guided under the press roller 3, through which the film 6 is pressed onto the printing blanket 1.
• an anti-adhesive intermediate layer 9 is inserted between the layers of the film 6, which is wound on a driven shaft 8.
• the film 6 is expediently adhesively bonded to the printing blanket 1, for example glued.
• thermoplastic film comes to the processor in roll form, the intermediate layer 9, for example paraffinized paper or a removable plastic film, being used to prevent the layers of the film 6 from sticking together.
• the film 6 is placed on the printing blanket 1 such that the actual adhesive or adhesive layer 10 faces the top of the printing blanket 1, while the thermoplastic resin layer 11 now faces the surface of the printing substrate consisting of the printing blanket 1 and the film 6 forms.
• the film 6 is expediently manufactured by a manufacturer who is set up for film coatings of this type. In this way, the printer receives a finished thermoplastic covering
• the printing blanket 1 is driven continuously during the application process and the film 6 is pressed with the printing blanket 1 via the press roller 3. After covering the tape, the beginning of the film is expediently moved over a few centimeters so that a double coating is present at the seam. In the area of this double coating, both film layers are cut through, the excess film layers are removed and the film ends are joined again. The machine is now ready for printing.
• the procedure for removing film 6 is similar.
• the film 6 is pulled off at the seam, guided around the press roll 3 and rolled up by a winder 8, see the film guide shown in dashed lines. This process also takes place, with the exception of pulling off the film 6 in the seam area, with the printing blanket 1 moving continuously.

Landscapes

• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Printing Plates And Materials Therefor (AREA)
• Screen Printers (AREA)
• Printing Methods (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=4313024

Family Applications (1)

Country Status (11)

Cited By (2)

Families Citing this family (1)

Citations (3)

• 1978
  • 1978-06-19 CH CH665978A patent/CH620320B/xx not_active IP Right Cessation
• 1979
  • 1979-06-15 NL NL7904703A patent/NL7904703A/xx not_active Application Discontinuation
  • 1979-06-18 ES ES481652A patent/ES481652A1/es not_active Expired
  • 1979-06-18 IT IT23694/79A patent/IT1121837B/it active
  • 1979-06-19 GB GB8004961A patent/GB2043539B/en not_active Expired
  • 1979-06-19 AT AT0900779A patent/AT368449B/de not_active IP Right Cessation
  • 1979-06-19 JP JP50089379A patent/JPS55500561A/ja active Pending
  • 1979-06-19 DE DE79CH7900090T patent/DE2952881D2/de not_active Expired
  • 1979-06-19 WO PCT/CH1979/000090 patent/WO1980000068A1/de unknown
• 1980
  • 1980-01-29 EP EP79900621A patent/EP0016024A1/de not_active Ceased
  • 1980-02-05 SE SE8000924A patent/SE8000924L/xx unknown

Patent Citations (3)

Also Published As

Similar Documents

Legal Events