NL9302237A - Wire sieve material, method of manufacturing it, and a sleeve made of such a sieve material. - Google Patents

Description

Brief designation: Wire sieve material, method of manufacturing it, and a sleeve made of such a sieve material.

The present invention relates to a wire screen material, particularly intended for screen printing.

Such a material is known and is generally made by weaving, braiding, knitting or the like of a thread-like material.

The final screen printing material is obtained by pattern-covering the holes, for example by covering the holes with a photosensitive lacquer or the like, and then exposing the lacquer in a pattern-wise manner, after which the exposed or non-exposed areas (depending on the type paint). Furthermore, the holes can be covered with a lacquer, wherein after curing of the lacquer with the aid of, for example, a laser or the like, the lacquer is burnt away in patterns.

During screen printing, a printing medium, such as ink, is pressed through the holes of such a screen onto a substrate to be printed by means of a squeegee.

The print quality with these woven, knitted or braided screen materials is insufficient for many applications, since the surface is relatively uneven and channel formation can occur between the screen wires and the substrate to be printed, resulting in loss of contour sharpness due to undesired smoothing of the pressure medium over the substrate.

Screen printing sieves which do not have the said drawbacks are thin-walled flat metal plates or seamless thin-walled metal cylinders, which are provided with holes. This material can be manufactured by providing a thin metal plate or a thin-walled metal cylinder with a photosensitive lacquer layer, which is exposed and developed in accordance with the desired hole pattern, after which an etching operation takes place to obtain the holes. It is also possible to galvanically grow this screen material on a conductive substrate, which is suitably provided with an insulating lacquer in pattern. In the latter operation, a roller can be used, on which local lacquer is applied, or a roller, which is patterned with pits, in which the lacquer is applied.

Previous techniques, however, are quite complicated, environmentally unfriendly and expensive.

The present invention aims to provide a wire screen material which has the advantageous printing properties of the latter metal sieves, but can be manufactured in a simple and inexpensive manner and from a variety of materials. The screen material according to the invention is therefore characterized in that the holes are bounded by locally interconnected thread pieces in such a way that an at least substantially flat non-woven screen surface is obtained.

This sieve material can be manufactured inexpensively from a wide variety of thread types, in which both the dimensions and the shape of the holes can be adjusted, while an at least substantially flat sieve surface is always obtained. As discussed earlier, this is particularly desirable in screen printing. The method of manufacturing the screen material is environmentally friendly since it does not require etching or electroforming.

The screen material according to the invention is not limited to screen printing, but can also be suitably used for, for example, filtration, without contamination which is difficult to remove, as is the case with woven, braided or similar screen material. The sieve material according to the invention is also suitable for use as temperature-resistant filters, for example for flue gas filtration, as a wire skeleton for catalyst masses, or for use as embossing tools. The screen material itself can also be applied to a support, after which the holes are filled with lacquer and a screen material can be grown by means of galvanic techniques on the screen material according to the invention to produce the aforementioned thin-walled, metal-perforated products.

The wire used in the screen material of the present invention is not particularly limited and may have a round, oval, square, rectangular, triangular or other desired cross-section, and may even have an approximately strip-like shape.

In the present description, by "locally" connecting wires together is meant to connect both pointwise and some distance, since as will be further explained hereinafter by choice of a pattern of connection points, i.e. spaced points or groups nearby spaced points, or uninterrupted connections over a greater distance, very different sieve shapes can be obtained.

Preferably, adjacent wire sections, each comprising two or more pieces of wire, extend uncrossed in substantially the same direction.

Threaded pieces are intended to mean those wire sections which extend between two connecting points. Wire parts comprise several pieces of wire.

By allowing adjacent thread parts to run uncrossed, a non-woven substantially flat screen surface is obtained, which exhibits advantageous printing properties.

When a part of the screen material of the previous embodiment according to the invention will be examined in more detail, clearly substantially parallel thread parts are visible, which are locally connected to each other.

The sieve holes can be formed in many ways, but the sieve material advantageously consists of zigzag-shaped wire parts, which are locally connected to each other at the tips. Such a material can be manufactured in a simple and reproducible manner, as will be discussed below. By zigzag is meant a sawtooth shape, sinusoidal shape, flattened sawtooth shape, or an intermediate form thereof.

According to another aspect of the invention, several wire pieces form a wire part, and the material comprises at least two groups of wire parts, wherein the wire parts per group run substantially parallel and those of another group cross on one side, and the wire parts at the intersections by melting and / or blending are interconnected such that an at least substantially sieve surface is obtained.

In this embodiment, a nonwoven material is obtained, with each group of threads extending in a given direction being on one side of another group of threads. This embodiment again provides a flat screen surface, as is particularly desired in screen printing.

In particular, the wires in this embodiment are linear, so that the number of holes per linear cm of the sieve material, and thus the dimensions of the holes, can be easily controlled. It will be clear that with two groups of linear wires four-sided openings are obtained, while three groups of wires can also provide triangular and even pentagonal and hexagonal openings.

The wire material used for the screen material according to the present invention is not particularly limited, but it is preferred that this material, as well as the connection method of the wire pieces, is mutually selected such that the final screen material is dimensionally stable. In this way it is prevented, for example, that a rotary screen printing cylinder manufactured from said screen material, or a screen plate, becomes undesirably and irregularly deformed and becomes unusable or provides uneven printing results.

The wire of the screen material advantageously consists of a weldable material, and particularly advantageously of an electrically conductive material. Due to the electrical conductivity and durability, metal wire is preferred; after all, wire mesh sieve material can easily be additionally reinforced by preferential electroplating, or coated with a corrosion-resistant metal, or provided with a coating for another purpose.

Preferably the sieve material according to the invention has at least 15 holes per stretching cm and more preferably at least 50 holes per stretching cm. Such screen materials are particularly suitable for screen printing.

Furthermore, a cylinder is provided of screen material intended for rotary screen printing, which is characterized in that the screen material is a screen material according to the invention.

The invention also provides a method for manufacturing a sieve material according to the invention, which method is characterized in that wire parts are placed next to each other, the wire parts are locally connected to each other and then the sieve holes are formed by deformation of the wire parts. Depending on the connection method, the wires are placed at a short distance from each other or against each other. For example, when using soldering techniques, in which material is supplied at the location of the connection, some distance between the wire parts will not be a problem, while when welding with a laser the wire parts preferably lie against each other.

In another embodiment, the method for manufacturing a sieve material according to the invention is characterized in that wire parts are suitably preformed and then locally connected to wire parts, which may or may not be deformed.

Both methods provide a sieve material, which consists of wire parts, which extend unchecked and in substantially the same direction.

The wire parts are preferably connected to each other on a support, with a roller being particularly preferably used as a support. In this way, a cylindrical sieve material can be obtained. For this purpose, one or more wires, preformed or not, are wound around the roller, the number of wires, the size of the cross-section of the wires concerned, and the winding method determining the pitch. Unclosed annular wire parts can also be placed on the roller, which are then locally connected and finally the sieve holes are formed.

In particular, the wire parts are locally connected to each other by laser welding, whereby the laser can operate continuously or intermittently (pulsating). Apart from welding, many other joining techniques can be mentioned, such as soldering, gluing, blending etc.

Finally, the invention provides a method for manufacturing a sieve material according to the invention, which is characterized in that groups of wire parts are successively placed on a support at an angle to each other, the wires per group being laid such that they are substantially run parallel to each other at some distance from each other, after which the wire parts at junctions are joined together by melting and / or blending.

Here too, for the manufacture of a seamless cylinder of sieve material, the winding of wires on a roller is preferred, whereby by setting the pitch of the wires to be wound, the mutual distance of the wires per group can be adjusted and thus the number of holes per linear cm of the final screen material produced. The melting and / or liquefaction can be carried out under the influence of temperature increase and / or pressure increase or the like.

In this method, it is preferable to subject the screen material to a flattening operation after manufacture, such as, for example, planing, sanding or calibration.

In order to simplify said melting and / or flowing, the wire parts of at least one group preferably consist of plastic. If desired, such plastic wire parts can be provided with a metal layer after completion of the screen material in a manner known to those skilled in the art.

In order to impart additional reinforcement to the screen material according to the invention, or to coat it for another purpose, it is preferable to carry out this by means of galvanic techniques known to those skilled in the art. A suitable technique for this is the preferential growth of a metal layer.

The wire material used in the method according to the invention is preferably a hard hair material. Examples are metals which can be cured by nitriding, for example, or hardenable plastics. All this is particularly advantageous if, for example, the wire has to be wound before joining, so that some flexibility of the wire is desirable. The ability to be cured provides the ability to give the final product the required strength, dimensional stability, hardness, or abrasion resistance.

Furthermore, a sieve material is obtained, which has been obtained by subjecting a sieve material according to the invention to an electrolysis in an electrolysis bath, which bath contains at least one organic compound with at least one unsaturated bond, which does not

group, and exhibits the properties of a second class brightener, with the openings in the final screen material substantially corresponding to the openings in the starting screen material. In this connection, reference is made to EP-B-0 038 104 of Applicant, which describes a method for preferentially growing a metal on a sieve skeleton in an electrolysis bath. This method can be grown substantially perpendicular to the plane of a screen.

Finally, the invention provides a wire material, comprising locally interconnected substantially linear wire parts, which is evidently intended for use in the manufacture of a screen material according to the invention. With this wire material, the sieve holes are not yet formed by deformation of the wire parts, but all wire parts are still substantially next to each other.

The invention will be explained in more detail below with reference to the appended drawing, which shows:

Fig. 1 an embodiment of sieve material according to the invention;

Fig. 2 shows the screen material of FIG. 1 subjected to additional horizontal deformation;

Fig. 3 another embodiment of the screen material according to the invention;

Fig. 4 is yet another embodiment of the sieve material according to the invention with zigzag wires and linear wires;

Fig. 5 yet another embodiment of the sieve material according to the invention with rectangular holes;

Fig. 6 a-e examples of wire cross sections;

Fig. 7 shows a schematic view of welded adjacent adjacent wire parts with round section;

Fig. 8 is a sectional view of Fig. 7 taken on the line VIII-VIII;

Fig. 9 screen material according to the invention, obtained by forming the holes of the welded material according to fig. 7;

Fig. 10 is a schematic view of locally welded wire parts of oval section;

Fig. 11 is a section of Fig. 10 taken on the line XI-XI;

Fig. 12 sieve material according to the invention, obtained by forming the holes of the welded material according to Fig. 10;

Fig. 13 an embodiment of screen material according to the invention with crossing wires;

Fig. 14 is a sectional view of FIG. 13 taken along line XIV-XIV;

Fig. 15 is a sectional view of FIG. 13 taken on the line XV-XV;

Fig. 16 is a schematic representation of an apparatus for manufacturing a sinusoidal wire;

Fig. 17 is a schematic representation of a device for winding wire around a roller, and locally connecting adjacent wires;

Fig. 18 is a schematic of multi-strand winding;

Fig. 19a is a schematic representation of a continuously operating screen material manufacturing apparatus according to the invention prior to hole formation;

Fig. 19b is a cross section of the support arm with wound and welded cylindrical material;

Fig. 19c is a cross-sectional view of another embodiment of the suspension arm of FIG. 19a; and FIG. 20 is a schematic representation of a device for forming screen holes.

Fig. 1 shows a first embodiment of a sieve material according to the invention made of iron wire, with wire pieces 1 and connecting points 2. A wire part 3 is indicated by an hatching. In this embodiment of the screen material, wire parts 3, comprising a plurality of wire pieces 1, are joined to one another at connection points 2 by welding. This embodiment can be manufactured by placing linear wire parts 3 next to each other, then suitably joining them pointwise, for example by welding with a laser, and subjecting the material thus formed substantially transversely to the wire parts in order to pull the screen holes 4. Also, wire parts 3 provided with a zigzag shape can be welded together at the tops, so that the holes cannot be formed.

In Fig. 2, the material of Fig. 1 is shown, the forming of the holes, by drawing, as seen in the figure, has continued in the horizontal direction, so that the sieve holes 4 have become diamond-shaped.

Fig. 3 shows an embodiment of the sieve material according to the invention, wherein the wire parts 5 are sinusoidal and consist of wire pieces 6, which delimit sieve holes 7. The sinusoidal wire parts 5 are connected to each other at the tips at 8.

Fig. 4 shows another embodiment of the screen material according to the invention, comprising wire parts 9 and 10 with wire pieces 11 and 12, respectively. The wire parts 9 are linear and the wire parts 10 are sinusoidal. It will be clear that this embodiment cannot be manufactured by placing wire parts next to each other, connecting them in a point-wise manner and then forming the sieve holes, but that the wire parts 10 must be made prior to the connection with the wire parts 11 of said sine shape to provide.

Fig. 5 shows an embodiment according to FIG.

1 with threaded parts 14, which comprise two types of threaded pieces 15 and 16, respectively, of different length, which delimit rectangular sieve holes 17. This embodiment can be obtained by placing wire parts next to each other and connecting them in a point-wise manner according to a suitable pattern.

In view of the foregoing, it will be clear that by choosing the wire thickness, the wire material, the position of the connection points, the degree of opening of the sieve holes, etc., the shape and dimensions of the sieve holes can be varied in very different ways. be varied.

The thread shape used in the sieve material according to the invention is not very limited. Fig. 6a-e show a round, square, triangular, rectangular and oval wire cross section, respectively, all of which are suitable for use in the invention. Triangular and oval cross-sections are preferred, while the latter is most preferred. When a triangular wire cross section is used, a screen will be obtained with an approximately conical hole shape on one side, which easily detaches material to be sieved in sieving applications and is not clogged when material is supplied on the flat side, which is also advantageous in screen printing application. When an oval wire cross-section is used, a sieve material is obtained which has many similarities with the electroplated sieve materials discussed in the description introduction, which in particular have good printing properties.

Fig. 7 shows juxtaposed metal wire parts 18 with welding points 19, a section along line VIII-VIII of which is shown in FIG. When the interconnected wire members 18 of FIG. 7 are deformed in the direction indicated by the arrows, the structure schematically shown in FIG. 9 is obtained, with screen holes 20. It will be appreciated that the shape of the holes can be varied appropriately, as discussed earlier.

Fig. 10 schematically shows adjacent wire parts 21, which are locally connected together at some length at 22.

Fig. 11 shows a section along line XI-XI in FIG. 10, in which it is clearly visible that the wire parts have an oval section.

In Fig. 12, a preferred embodiment of sieve material according to the invention is shown, which is obtained by subjecting the wire material according to Fig. 10 in the direction of the arrows to a tensile force, so that the sieve holes are formed. These hexagonal screen holes, in particular in combination with an oval wire cross section, have very advantageous properties for screen printing, since hexagonal holes approximate the traditional form of screen printing templates and an optimum distribution of screen holes over the surface is also obtained with an additional strength compared to otherwise formed holes.

The wire pieces 21 'are connected to each other over a short length by welding points. It will be clear that a smaller number of spaced welding points, or a continuous weld, can also be used. A thread piece 21 'includes a thread portion starting from the center of a weld to the center of an adjacent weld in the same thread portion 21. When the hexagonal structure of Fig. 12 is further stretched (opened), a substantially rectangular hole shape will be obtained, the holes being staggered (masonry structure).

For welding metal wires, a soldering medium such as tin, lead, lead-tin, brass, silver or the like can also be supplied during welding, with or without a flux (fluxes). Obviously, a similar technique can also be used in joining wires from other materials.

Fig. 13 shows another embodiment of sieve material according to the invention, in which two groups of wire parts 24 and 25, respectively, are shown, which are interconnected at the intersections by melting and / or blending and through which sieve holes 26 are formed.

Fig. 14 and 15 show the section along lines XVI-XVI and line XV-XV, respectively. As is clear, a sieve material with a substantially flat sieve surface is also obtained in this embodiment.

The connection of such crossing wires can be performed by techniques known to those skilled in the art. For example, the wires at the intersections can flow together by welding or the like, or by applying pressure on the spot, whether or not at an elevated temperature, i.e. by arranging the groups of wire parts 24 and 25 in a crosswise manner and then between compressing unheated press plates or the like. A quartz radiator can also be used for forming connections at the intersections by melting and / or liquefying.

The material of the wire used for the screen material according to the invention is not very limited, but in particular for the production of screen printing material it is preferred to use metal wire, since it can be easily welded locally by means of, for example, a laser , and any previously applied metal wire bends are dimensionally stable. Examples of suitable metals are: iron, steel, copper, nickel, chrome, etc.

In the embodiment shown in Fig. 13, it is preferable to design at least one of the groups in plastic, so that the connection is simplified by liquefaction at the intersections.

The sieve material according to the invention can be subjected to additional coating steps after being manufactured, in order to reinforce this, for example. For example, the screen material, optionally after making its surface conductive, in the case of plastic wire, can be plated in a known manner with a suitable metal.

The material can also be subjected to a flattening operation after manufacture and for a possible metallization, in order to remove irregularities. Examples are planing, sanding, calibration, etc.

Fig. 16 schematically shows a device with two gears 27 and 28, between which a wire 29 is fed via guide rollers 30 and 31. By driving said gears 27, 28 in the indicated direction, a zigzag-shaped wire is obtained. Optionally, the wire, if it is a metal wire, may be heat-treated after the deformation operation, so as to give the wire dimensional stability, due to the curing properties of the selected material.

Fig. 17 schematically shows a device for manufacturing sieve material according to the invention, in which a wire 33 is wound around a roller 32. The roller is turned in the direction of the arrow and the wire 33 is extracted from a reel 34. During the winding, the reel 34 can be moved parallel to the roll 32 in the winding direction. Reference 35 schematically shows a moving laser device, which locally welds the wire 33 wound around the roller 32. The laser device advantageously comprises positioning means, which can comprise a probe for determining the position of the welding locations relative to the wire parts, on the basis of which the position of the laser can be adjusted with the aid of suitable laser displacing means. After the roller 32 has been threaded 33 along its entire length and locally welded, the material so manufactured is removed from the roller 32 and subjected to a longitudinal tensile force, thereby increasing the length of the diameter and the sieve. holes are formed. It will be clear that the diameter reduction, the length increase of the screen cylinder and the hole shape and size, respectively, depend on the mutual position and dimensions of the connections, the wire diameter and the degree of deformation.

When the wire 33 is passed through the device of Figure 16 prior to winding, the final material need not be subjected to a deformation treatment. The mutual positioning of the tips of the already wound wire with respect to the wire still to be wound can be regulated by appropriately controlling the thread tension in the feed during winding.

In Fig. 18 the same roller 32 is shown, with multiple wires 33, of the same type and shape or not, being wound simultaneously, so that the surface of the roller can be covered with wire more quickly at the same rotation speed. When winding with several wires in this way, the winding pitch will increase for each individual wire.

As a result, when the screen material removed from the screen after the roll 32 has been welded, the screen holes are formed by a longitudinal tensile force, the material will twist by itself. This means that at least one of the fastening parts must be rotatably mounted when pulling on the ends of the screen cylinder.

Fig. 19a schematically shows an apparatus for the continuous production of screen material according to the invention. Herein is present a reel 34 from which wire 33 is extracted. Although a reel is shown, of course, as discussed earlier, several wires can also be wound simultaneously.

35 denotes a drive mechanism of a mandrel 36 on which the wire 33 is wound. The wire 33 is passed through a wire feed control unit 37 to the mandrel 36. The wire 33 is passed between a stationary stop 38 and the already wound material, whereby the already wound material is forced to the left as seen in the figure during winding. During said displacement, the wire is locally welded with the aid of a fixed laser 40. Many types of lasers are suitable for this. Depending on the thread pitch, the winding speed, the welding design and the welding pattern, the laser can work continuously or intermittently.

The mandrel 36 used is preferably interchangeable, so that cylinders 39 of different diameters with as many standard sizes (report sizes) and cross-sectional shapes can be manufactured. Different cross-sectional shapes mean oval, triangular, quadrangular, etc. cross-sections.

A movable trestle is shown schematically at 41, which serves to support the material 39 moving from the roller 36 by means of a supporting arm 42.

The support arm 42 of the trestle 41 is preferably in the form of a freely rotating roller and more preferably the support arm is designed in such a way that it comprises several freely rotatable rollers arranged around the inner circumference of the manufactured cylinder, so that the manufactured cylinder material multiple places can be supported. Fig. 19b shows a section of the support arm 42 of FIG. 19a with manufactured cylindrical material 39. FIG. 19c shows a preferred embodiment of the support arm 42 in section, which includes four support rollers 44 for supporting the material 39. The mutual position of the rollers is advantageously adjustable.

With the device according to the invention, the pitch is adjustable, for example by placing an annular stop with an oval cross section at a suitable angle around the mandrel.

At 43, a movable cutting device is shown schematically, which serves to cut this material after a certain length of material has been formed. After cutting, said cylindrical material can be moved with the aid of the trestle 41. The arm of another trestle can then be placed in the material 39 moving from the roller 36. The support arm 42 on the trestle 41 can suitably be adjusted in height, for instance with the aid of a screw spindle 45 or the like.

Obtaining lengths of the cylindrical material can also be separated from one another in another way. For example, by interrupting the laser for some time after a certain duration of operation of the device, a number of turns of wire are not welded. This number can be selected so that at a suitable time the already manufactured cylindrical material can be pulled off the mandrel, the non-welded wound wire material being stretched as a spiral and cut. This has the advantage that only one wire needs to be cut as opposed to cutting a cylinder completely.

Fig. 20 schematically shows a device for forming sieve holes with a forming device 46. With this device 46, the material 39 with sieve holes that have not yet been formed, as schematically indicated at 47, is forced in the direction of the arrow, so that the sieve holes in material 39 are formed, as indicated at 48. It will be appreciated that the pulling member (not shown) with which the material 39 is moved through the forming device must be rotatably disposed, since depending on the method of winding the wire (or wires) a certain amount of rotation during forming of the sieve holes will occur. It may be advantageous to arrange a carrier body in the product during the formation of the holes by means of the forming device 46, in order to be able to perform this operation in a reproducible manner.

If in a production process large numbers of thread cylinders are produced, the holes of which have not yet been formed, the successive thread obstacles may gradually form the sieve holes, which means that successively cylinders of slightly decreasing diameter can be produced which can be interlocked. be pushed. The transport and storage thereof is thus considerably simplified. The screen holes of these cylinders can then be brought into the desired final shape at a desired moment. The same is true of longitudinally wound roller material, the diameter of which increases and the length decreases as the screen holes are formed.

The invention is not limited to the above embodiments, since the screen material can also be manufactured in flat form by placing thread parts, which optionally consist of one and the same thread, next to each other on a flat support, then connecting them locally and then forming the screen holes.

Also, in the case of cylindrical sieve material, the wire can be wound in the longitudinal direction of a roller, for example projections such as pins may be present around the circumference at the ends of the roller, so that the wire can be wound back and forth in the longitudinal direction. The wire can also be wound crosswise over the crosscut ends of the roller before winding in the longitudinal direction. When such a cylinder consisting of wire material is welded locally, contrary to what has been described in the foregoing holes will result in a diameter increase and a length reduction in the cylinder. For example, an expandable core may be used for this operation, or the wound wire material may be moved in opposite directions over the forming device 46 of FIG. 20 to form the screen holes.

To manufacture the embodiment of the sieve material according to Fig. 13, in cylindrical form, a wire can be wound around a support, as shown in Fig. 17 or 18, in such a direction that spaced apart from one another thread parts are obtained, after which optionally the same thread can be wound in the opposite direction with corresponding desired pitch over the first group of thread parts. In addition, several groups of wires can be wound, after which the wires are joined together at the intersections using suitable techniques known to those skilled in the art, such as welding, pressing at elevated temperatures by melting and / or blending.

Using the above-described method, sieve material according to the invention can be manufactured with a very diverse number of holes per linear cm and hole shape, while in the same way flat sieves can also be produced. These can be produced directly or by longitudinally cutting cylinders according to the invention.

Finally, it should be noted that although substantially symmetrical sieve materials have been described in the foregoing, the invention is not limited thereto, since random deformed wires may also be arbitrarily connected to each other, so that flat sieve material of arbitrary sieve hole shapes and dimensions is obtained, which may be advantageous for certain applications. In particular, the so-called moire effects are suppressed.

Claims (24)

Wire sieve material in particular intended for screen printing, characterized in that the holes (4; 7; 13; 17; 20; 23; 26) are so arranged by locally connected thread pieces (1; 6; 11, 12; 15, 16; 18 '; 21') are limited to obtain an at least substantially flat non-woven screen surface. Sieve material according to claim 1, characterized in that adjacent thread parts (3; 5; 9, 10; 14; 18, 21), each of which has two or more thread pieces (1; 6; 11, 12; 15, 16; 18 ', 21') extend unchecked in substantially the same direction. Sieve material according to claim 1 or 2, characterized in that the material consists of zigzag-shaped wire parts which are locally connected to each other at the tips. Screening material according to claim 1, characterized in that a plurality of thread pieces form a thread part, the material comprising at least two groups (24, 25) of thread parts, the thread parts per group (24, 25) being substantially parallel, and that of to cross another group (24, 25) on one side, and that the wire parts (24, 25) are joined together at the intersections by melting and / or liquefaction, so that an at least substantially sieve surface is obtained. Sieve material according to claim 4, characterized in that the threads are substantially linear. Sieve material according to one or more of the preceding claims, characterized in that the wire material and the connection method are chosen such that the sieve material is dimensionally stable. Sieve material according to one or more of the preceding claims, characterized in that the wire of the sieve material consists of a weldable material. Sieve material according to claim 7, characterized in that the wire of the sieve material consists of an electrically conductive material. Sieve material according to claim 8, characterized in that the wire of the sieve material consists of metal. Sieve material according to one or more of the preceding claims, characterized in that the material has at least 15 holes per linear cm. Sieve material according to claim 10, characterized in that the material has at least 50 holes per linear cm. 12. Screen cylinder designed for rotary screen printing, characterized in that the screen material is a screen material according to one or more of the preceding claims. Method for manufacturing a sieve material according to one or more of claims 1-3, 6-11, characterized in that wire parts are placed next to each other, the wire parts are locally connected to each other and then the deformation of the wire parts sieve holes are formed. Method for the production of a sieve material according to one or more of claims 1-4, 6-11, characterized in that wire parts are suitably preformed and are subsequently joined point-wise with deformed or deformed wire parts. Method according to claim 13 or 14, characterized in that the wire parts are connected to each other on a support. Method according to claim 15, characterized in that a roller is used as the support. Method according to claim 16, characterized in that one or more wires, preformed or not, are wound around the roller. Method according to one or more of claims 13-17, characterized in that the wire parts are locally joined to each other by laser welding. Method for manufacturing a sieve material according to claim 4 or 5, characterized in that groups of wire parts are successively laid on an support at an angle relative to each other, the wires per group being laid such that they are substantially parallel to each other at some distance from each other, after which the wire parts are connected to one another at intersections by melting and / or blending. Method according to claim 19, characterized in that the wire parts of at least one group consist of plastic. Method according to one or more of claims 13-20, characterized in that the sieve material is subjected to a flattening operation after manufacture. Method according to one or more of claims 13-21, characterized in that the sieve material is plated. Screen material obtained by subjecting a screen material according to one or more of claims 1-11 to an electrolysis in an electrolysis bath, which bath contains at least one organic compound with at least one unsaturated bond, which does not

group, and exhibits the properties of a second class brightener, with the openings in the final screen material substantially corresponding to the openings in the starting screen material. Wire material comprising locally interconnected substantially linear wire parts, apparently intended for use in the manufacture of a screen material according to one or more of claims 1-3, 6-11.