FR2843053A1 - Continuous industrial process coating fibers or powder onto paper, metal or plastic web, prints paste onto web and passes it through coating box for deposition - Google Patents

Abstract

The web passes through printing rollers (2). These paste it all over with adhesive. They alternatively coat it with a regular- or irregular printed pattern of adhesive. The web enters a trough (3). This contains powder or cut fibers, which adhere to the freshly-pasted locations. A recovery system with brushes (4) lifts surplus powder or fibers from the paper. It is returned by gravity or through a suction system, to the trough. The web passes between two pressure rollers (5, 6), causing the powder or fibers to penetrate more deeply into the adhesive layer. A blowing/aspiration system in the trough, prevents agglomeration of the contents. It forms and homogenizes a suspension of powder or fibers, whilst the web passes through the trough.

Description

r t r s 2843053 Certain security, filtering, or

  of absorptions require to distribute on all or part of a support cut fibers or powders with particular properties. The proposed method makes it possible to produce, on an industrial scale, coils of synthetic, metallic or paper support, completely or partially coated in random or predetermined positions, of

powder or fiber.

  A support strip (1) passes through a printing unit (2) and is glued on one of its faces. Before the glue dries, the strip (1) passes

  in a container (3) filled with powder: the said powder then adheres to the fresh glue.

  At the outlet of the tank (3), a brush system (4) sweeps the excess powder too loosely attached to the support (1) and this surplus falls back into the tank (3). The strip then passes through a drying box (7) to dry the glue and finally

  the support (1) with its powder coating can be wound.

  The gluing of the strip (1) can be a total flat or a repeated imposition pattern such as for example a grid of dots of 1 millimeter in diameter.

  repeated every centimeter according to the quantity to be deposited depending on the surface.

  In a version of the invention, in rotogravure for example, with an imposition of glue in pattern and not in solid, the gluing cylinder may not be meshed. Imposition is no longer regular but random depending on the slippage between the support and the cylinder. This random deposit can be even more irregular if the said gluing cylinder can move slightly along

the axis supporting it.

  In a variation of the invention, at the outlet of the powder container (3), the strip (1) passes between two rollers (5 and 6) under pressure to force the powder to penetrate more deeply into the adhesive layer, in order improve the grip of the said powder. In a variation of the invention, a new sweeping of the strip can be carried out after drying to keep only the strongly adhered powder

  to support. In this case the surplus can be recovered by a suction system.

  In a variation of the invention, in order to avoid any agglomeration of powder and to homogenize the grip of the material when passing through the tank (3), a blower / suction system is integrated into this tank to circulate the powder

permanently.

  The exposed system for the powder can be transferred to a fiber deposit

  cut on an identical principle.

  -2 Figure 1 proposes an embodiment of the invention with a rotogravure printing unit (2) and shows an example of passage of the strip (1)

  for the different stages of the process.

-3

Claims (3)

  1. Continuous industrial process for depositing powder or fibers cut on a paper, metallic or synthetic support strip, characterized in that: The strip passes through a printing unit (2), intended to paste, totally or partially according to regular or irregular taxation, the medium. The strip then passes into a bin (3) filled with powder or fibers   cutouts that adhere to freshly glued areas.   A scanning (4) and recovery system makes it possible to remove the excess powder or fibers from the strip and by their fall or their aspiration to return to the tank (3).   2. Method according to claim 1 characterized in that the support strip passes between two rollers (5 and 6) under pressure to penetrate the   powder or fibers deeper into the glue layer.   3. Method according to claim 1 characterized in that a blower / suction system is added to the powder (or fiber) bin, in order to avoid any agglomeration of powder (or fibers) and to homogenize the catch the   material when passing through the tank.