DE1909863A1 - Stencil cylinders, in particular for rotary film printing machines and processes for their production - Google Patents

Description

Patent attorney

Dipl. Phys. Dr. Walther Junius

3 Hanover, Abbestr. 20th

February 24, 1969

Dr.J / Ha.

My file: 1622

ELITEX - Zavody textilniho strojirenstvi, generalni reditelstvi, Liberec - Czechoslovakia

Stencil cylinders, in particular for rotary film printing machines, and methods for the production thereof

The present invention relates to a stencil cylinder, in particular for rotary film printing machines and a method for its production.

So far, two types of stencil cylinders and two methods for their production are known.

For the older types of stencil cylinders, phosphor bronze fabrics with low thread counts and plain weave are used and a chain in which a warp wire alternates with a weft wire. This stencil is made in such a manner that the phosphor bronze cloth is twisted into a cylinder shape becomes and in this form by welding

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in the weft direction or after the pattern has been applied is connected in the plane according to the pattern.

The newer types of cylinder stencils consist of cylindrical foils, which are based on electroplating Kind to be produced in which «. Openings chemically are etched out that let the printing ink through.

There are also stencils made of synthetic materials, for example polyamide fibers are known among others. These stencils however, they are used in particular in a flat shape, while in a cylindrical shape they are used practically at all cannot be used for the reason that they are not self-supporting in the form of a cylinder.

The main disadvantage of the older types of cylinder templates is that they have a small tensile strength in the diagonal direction as well as a small weld strength, especially when the welding is carried out according to the pattern, as well as when the weld seam has a different permeability with regard to the Has remaining metal fabric from which the stencil is made, so that there are often marks when printing. In addition, phosphor bronze also has a small disadvantage. Resistance to certain printing inks, for example when using alginate thickeners, so that the pattern has a shorter service life.

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In the case of the second type of cylinder stencils, the Bach part mainly orders that these are very easily damaged and have a smooth surface, which results in considerable economic losses as a result of damaged stencils and a short life of the pattern. As a result of the expenditure costs. The production is; the stencils are not very common, - - ^:. ;. .- · .. ■■ - ■.

The present invention overcomes these disadvantages.

. consists in the fact that the cylinder template consists of a metal fabric with a plain weave _9, for example of phosphor bronze, which is seamlessly connected and nickel-plated and whose chain is formed from groups of three of I-wire, which are regularly distributed along_ the entire width of the fabric in a triangular shape, " that the apex of: triangle is alternately above and .'unterhalb of the shot, _and, that the distance between two, adjacent.:. _v groups of three ICE ttdrahten the tree resembles that so arranged by "a triplet. Eettwires ingested, becomes i. ·· ^. ...... ■: - ', .- ■, ...- ■. ". -' ■ -> ■ = - - / = ■.: · '

The manufacturing uni ^ ve ^ f.ahren, the. Cylinder chäblone of the ν present <| en _i :, E ^ | ^ n ^ ung, consists in {that the seamless connectionuni ^ bgidgr.i.ends.äes metal fabric -in a ■ · =: cylinder.! Orm ^ through ^ A wire wire is put in place, which is coated with silver solder and

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that the weft wire mentioned is inserted between the ends of the warp wires on the connection ends, which completely surround its perimeter and by means of resistance soldering is connected, after which the resulting stencil cylinder is provided with reinforcement flanges at its ends and nickel-plated without current.

The essence of the invention is based on one in the drawing Schematisoh illustrated embodiment explained in more detail. Show it:

Pig. 1 shows the structure of the metal fabric from which the stencil cylinder according to the present invention Invention is made;

FIG. 2 shows a cross section through the fabric according to FIG in the warp and weft directions? '

Fig. 3- an embodiment of the connection of the cylinder template in cross section in the warp direction;

Figure 4 is a permeability diagram of the stencil cylinder. ders of the present invention}

5 shows an overall view in perspective of the cylinder template of the present invention.

The stencil cylinder of the present invention consists of a jacket 4 made of a metal fabric in plain weave, for example phosphor bronze, which is formed by groups of three warp wires 1 and a weft wire 2 (Fig. 2), the groups of three warp wires being regular along the entire width of.

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Tissue arranged in a triangular shape, the apex of which is alternately above and below the weft wire 2. The distance between two neighboring groups of three of the warp wires mentioned resembles the space, which is occupied by a group of three so arranged warp wires. The tissue is in a cylinder twisted together and put both ends together in such a way that that between them the weft wire 2, which with Silver solder is coated, is inserted, which after forms a seamless connection with resistance soldering. Both ends are solidified by gluing flanges 5 and the cylinder stencil is electrolessly nickel-plated by a nickel layer in each case Thickness of the quality of the metal mesh in terms of it Depends on thickness.

The manufacturing method of the cylinder stencil of the present invention is as follows

The metal fabric with plain weave, e.g. made of phosphor bronze, is cut in the weft direction according to the dimensions, by the circumference and length of the cylinder template, which are to be produced from it are given. The edge of the tissue becomes a sehusswire taken out and in its place a weft wire 3 smaller, diameter inserted, but the one on his ■ Surface is covered with silver solder, after which both Fabric edges are placed one on top of the other in such a way that the mentioned weft wire 3 is completely surrounded by them. , Then along the entire length of the wire 3 Resistance soldering using a disk electrode

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taken, whereby the solder is melted and the metal to be soldered diffuses. Thereafter, both ends of the cylinder template produced in this way are provided with puddles 5, which are connected to the dumbbell 4 by gluing. Once this adhesive bond has hardened, the stencil created in this way is suspended in a special nickel-plating bath, the composition of which enables electroless nickel-plating. The degree of nickel plating depends on the thickness of the metal mesh from which the cylinder stencil is made, which means that in the case of metal meshes of a self-supporting character, ie coarser _s, the nickel plating is only carried out to the extent that the mottled layer, the main purpose of which in this case is Protection of the fabric against chemical influences is sure to cover the entire surface of the warp and weft threads. In contrast, the nickel-plating of / finer metal fabrics, possibly single-chain fabrics with plain weave, in which only one warp wire is used, for the purpose of strengthening the template next to the one above The mentioned purpose is designed in such a way that the warp and weft wires, in addition to their connection achieved by weaving, are also connected by the Uiekel, which fundamentally influences their self-supporting properties

The advantage of the stencil cylinder produced by the process of the present invention is, in particular, that - the connection of both fabric ends has a minimum strength - of 95% of the fabric strength and often exceeds the latter,

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has the same permeability as the others Fabric from which the cylinder template is made is, the thickness of the stencil walls on the The connection point is the same as on the whole circumference, which gives the connection a seamless character and does not mark the printed material. In addition, the stencil is all the printing inks used chemically resistant, self-supporting and has increased tensile strength in the diagonal direction on.

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Claims (4)

Pat en t to sprue he 1. Stencil cylinder, especially for rotary film printing chinen, characterized, . that, for example, of phosphor bronze consists of a metal plain weave fabric., which is seamlessly connected, and nickel and its Zetteaus triads of Kettfäden.besteht which regularly% moderately along the entire width of the fabric in a triangular shape, are distributed, with the vertex of the triangles alternating above and below the weft and the distance of the adjacent groups of three of the warp wires equals the space covered by one Group of three warp wires arranged in this way is taken. 2. stencil cylinder according to claim 1, characterized, that the gap! layer covers the entire surface of the warp and weft wires while maintaining tissue character covered. 3. stencil cylinder according to claim 1, characterized, that the winding layer has the warp and weft wires of the fabric connects. 4. Method of making the stencil cylinder according to claims 1 to 3, "■■■■■." '- 9. - 909838/1065 ^ - BATH ORIGINAL characterized, that the seamless connection of both ends of the metal mesh by inserting a weft wire (3), "which is covered by a layer of silver solder, between the ends of the warp wires on the to be joined Edges that completely encircle the weft wire (3) surrounded and by means of resistance soldering with these is connected, is carried out, after which the such The resulting stencil is provided with flanges (5) on its ends and nickel-plated without current. 909838/1065 Lee rs ei ie