DE102008036389A1 - Method for manufacturing tubular hollow body, particularly tube made of polymer material with foil piece marked by laser radiation, involves connecting portion of foil piece with outer wall of tube - Google Patents

Abstract

The method involves connecting a portion of the foil piece (16) with the outer wall of the tube (10), where the foil piece comprises a laser sensitive material and a Radio-frequency identificationtransponder. The foil piece is heated during extrusion of the tube. The foil piece is cooled to connect the portion with the outer wall area (15).

Description

Background of the invention

The The invention relates to a method for producing a tubular hollow body, in particular a tube of polymer material with at least one under action of laser radiation markable piece of film.

It is known, tubes with at least one under the action of laser radiation markable piece of film to provide, with the film piece preferably at least one laser-sensitive material, since only a few polymer systems per se and without further laser-sensitive additions are laser markable. The laser-markable piece of film is usually, for example, with a barcode or an article number or a serial number or the like of the pipe to which the film piece is attached is, under the action of laser radiation marked to a unique To allow marking of the pipe. Likewise are also hot stamping foils known to be used in conjunction with heated signing wheels, colored identification letters or symbols, eg. B. for pipe marking, to sign on a polymeric tube.

laser Sensitive Materials, such as laser-sensitive pigments, which are mostly in the foil pieces are dispersing materials, which are the radiation of the respective Laser absorb and make a dark or light mark on the plastic of the foil piece cause. For example, the pigments are platy mica pigments, which consist of uncoated or coated mica, or to pigments that cause a color change in the plastic.

The Production of a tube with a laser markable attached to this Piece of film takes place in a known manner by extruding the piece of film or the film on an already extruded pipe section during the Extrusion production of the respective tube, along with a high technical effort.

at the extrusion production of large pipes, so pipes with a large inner diameter or outer diameter, which with a minimum extrusion rate of only a few cm per minute exit from the tool is extruding a piece of film or a foil strip very demanding in terms of production engineering, because the injection extruder in the extrusion is almost immobile, so that the residence time the hot ones Melt of the film piece or the residence time of the laser signature melt in the extruder, which is provided for extruding the film piece, becomes too large and the recipe of the foil piece or the film strip can be severely damaged thermally, accompanied with a limited Laser markability of the film piece or foil strip.

Underlying task

Of the The invention is therefore based on the object, a process for the preparation a tube of polymer material with at least one under action Specify by laser radiation markable piece of film, compared to known solutions a simple and practical production of pipes with at least allows a markable under the action of laser radiation film piece, and with the particular thermal damage to the film piece, which limits the laser markability, can be effectively avoided.

Inventive solution

These Task is according to the invention with a Method for producing a tubular hollow body, in particular a tube of polymeric material with at least one under the action of Laser radiation markable piece of film solved, the film piece at least a laser-sensitive material, wherein at least a portion of the foil piece with the outer wall of the tube cohesively is connected, and wherein the piece of film by heating a dimensionally stable state is at least partially convertible into a molten state, wherein in the method the tube is formed by extrusion, and wherein in a first step during the extrusion of the tube the at least one piece of film in a dimensionally stable state at least partially on an outer wall area an already extruded pipe section of the pipe applied is, after applying at least the portion of the film piece a flat contact to the outside wall area and in a second step during the extrusion of the tube the foil piece is heated, at least partially in a molten state to convict, and wherein in a third step, the film piece is cooled to at least the Partial area cohesively with the outer wall area connect to.

According to the invention, according to the first step of the method according to the invention, in contrast to known methods no extrusion of a piece of film in non-dimensionally stable molten state, but at least partially applying the film piece in a dimensionally stable state on an outer wall portion of an already extruded pipe section, so that after application at least a portion of the film piece has a surface contact with the outer wall region. The laser-sensitive material may be, for example, a laser-sensitive pigment, which the Strah absorbed laser radiation and causes a dark or light marking of the film piece, wherein the laser-sensitive material is preferably adjacent to a provided for the irradiation with laser light side of the film piece or adjacent to this embedded in the film piece to allow effective laser marking.

According to the invention in a second step during the extrusion of the pipe heating of the film piece, at least partially in a molten state to convict by a subsequent cooling of the film piece in the third step a cohesive connection between the Exterior wall area and at least to form the subarea. Preferably, the foil piece by heating completely or essentially complete in the molten one Condition convicted. Becomes the foil piece partly in the molten one State convicted, then will the warming preferably made in a way that in the molten state areas of the film piece to the outside wall area adjoin to after cooling an effective cohesive Compound that is dimensionally stable, between the outer wall area and at least form the sub-area, the film piece for this purpose according to the invention to a Temperature cooled which is below a melting temperature of the film piece, with the foil piece at a temperature greater or equal to the melting temperature at least partially in a molten state is present.

All in all seen by using the method according to the invention a significant reduction the cost of marking a pipe, ie the marking the extruded tube with a barcode, plain text, such as serial numbers, Identification numbers, etc., and the like, through lower investment costs possible, especially because, in contrast to the known method the extruder for applying the film piece, such as a strip extruder extruder, can be saved.

Further Advantages over The known method comprises an improvement of the contour sharpness Enable a thin, sharp edge application of the film or the film piece, the Enable the laser marking of slowly extrudable large tubes, a cost saving per signed pipe meter through a cost-effective, very thin foil piece in the form of a signing foil piece instead of the known use of a comparatively thick extruded Strip, a high-quality look, a high value appearance and a optimal contrast ratio.

at a particular practical embodiment of the method according to the invention In the first step, essentially the entire piece of film is placed on the Exterior wall area applied, wherein after application substantially the entire foil piece a flat Contact to the exterior wall area having. Thus, according to the invention, a compound created in which not only a subarea but essentially the entire film piece a cohesive Connection to the outer wall area or the outer wall having. Preferably also in this practical embodiment the foil piece by heating completely or essentially complete in the molten one Condition convicted. Becomes the foil piece partly in the molten one State convicted, then will the warming preferably made in a way that in the molten state areas of the film piece to the outside wall area adjoin to after cooling an effective cohesive connection between the outer wall area and the foil piece to build.

at a preferred embodiment becomes a piece of foil used, consisting of a mixture of a polymeric material and the at least one laser-sensitive material. The polymeric material may, for example, polyolefins, preferably PET, or have may be formed from these and the laser-sensitive material may be made be formed or have laser-sensitive pigments, wherein the laser-sensitive pigments in the polymeric material in the form of a polyolefin matrix can be embedded.

at this preferred embodiment can the foil piece for example, an additional UV protection of 0.1 to 5%, preferably 0.5 to 2%, the the polymeric material or the carrier polymer before degradation by UV radiation z. During an outdoor storage protects, but not in the range of wavelength 100 to 450 nm absorbed to the exposure by the respectively used Not to prevent labeling lasers.

The polymeric material can also be adhesion promoter for a laser-sensitive material have in the form of color pigments, with the film piece here, too additional UV protection of 0.1 to 5%, preferably 0.5 to 2% may have.

The polymeric material may also include at least one metal deactivator which prevents metal ion catalyzed degradation of the film piece material and / or contained color pigments during application of the film piece, for example, with a hot metal roll, with the film piece also providing additional UV radiation. Protection of 0.1 to 5%, preferably 0.5 to 2% can have.

at a particularly preferred embodiment of the method according to the invention becomes the foil piece at least partially by means of a heated contact pressure the outer wall area pressed wherein preferably a heated roller used as a contact pressure becomes. Here, a piece of film is preferably used, which with a backing detachable from polymer material is connected, wherein the polymer material of the carrier layer has a melting temperature which is larger as a maximum heating temperature on the film piece heated is going to the film piece at least partially in the molten state, wherein the contact pressure with the carrier layer is brought into contact with the film piece at least partially the outer wall area to press and wherein the carrier layer after forming the cohesive Connection of the film piece is disconnected.

So can be determined using a provided in the invention warming temperatures non-melting carrier layer, in particular in the form of a carrier film of polyester and / or PET can be formed, in a practical way a cohesive connection between the film piece or at least the subregion and the tube are produced. Again, then the film piece even from a mixture of a polymeric material and the at least consist of a laser-sensitive material. The polymeric material can For example, polyolefins, preferably PET, or have this may be formed and the laser-sensitive material may be made of laser-sensitive pigments be formed or have these, wherein the laser-sensitive pigments in the polymeric material, preferably in the form of a polyolefin Matrix can be embedded.

at In another particularly practical embodiment, a film piece is used which has at least one RFID transponder, wherein the RFID transponder preferably in the film piece is embedded. Alternatively, the RFID transponder can also be printed Circuit on the foil piece be printed. On the RFID transponder can in a known manner more Data relating in particular to the pipe or refer to this, stored and read out via radio transmission from an RFID reader become.

The can be produced by the method according to the invention Pipe, for example, a pressure tube, preferably made of PE and / or PP, or a gas pipe, preferably made of PE. The with the inventive method producible pipe can also be a sewer pipe or a seepage pipe or a telecommunications tube, in particular for recording may be provided by telecommunications lines.

alternative can the inventive method also intended for the production of an edge band (or edge band) which can be marked at least one under the action of laser radiation foil piece has, wherein the film piece cohesively with the edge band connected is.

alternative can a piece of film, for this a mixture of a polymeric material and at least one may be laser-sensitive material, also applied to the outer wall area be that it is not dimensionally stable form by flame spraying of the Mixture on the molding surface or the outer wall area is applied.

Brief description of the drawings

Hereinafter, an embodiment of the invention will be described with reference to the accompanying drawings, in which 1 schematically shows, inter alia, a pipe section produced by means of an extrusion device of a tube, together with a film piece according to the invention applied thereto.

In 1 schematically shown is the situation where a pipe 10 by means of an extrusion device 12 is extruded, according to the inventive method during the extrusion of the tube 10 on an already extruded pipe section 14 a film piece which can be marked under the action of laser radiation 16 has been applied and by means of a heated roller 18 in the form of a heated pressure roller 18 on an exterior wall area 15 of the pipe section 14 pressed and ironed on this wrinkle free essentially. The foil piece 16 is with a carrier layer 20 detachably bonded from polymer material, wherein the polymer material of the carrier layer 20 has a melting temperature which is greater than a maximum heating temperature on the film piece 16 through the heated roller 18 is heated to the film piece 16 at least partially convert to the molten state. The heated roller 18 has a contact with the carrier layer 20 on, after cooling the film piece 16 - Preferably by cooling the pipe section 14 by means of a cooling section, not shown - and the associated with the cooling formation of the cohesive connection between the outer wall region 15 and the foil piece 16 is separated from this.

According to the invention, the film piece 16 . which may for example also be designed in the form of a piece of a laser-markable hot stamping foil, a piece of film 16 a laser-markable film which can be produced in a film factory, wherein in this film production corresponding laser-sensitive materials, such as laser-sensitive pigments are dispersed in a polymeric base film to produce the laser-markable film. Also the carrier layer 20 may be a piece of a carrier film which is bonded in the film factory with the laser-markable film. The laser-markable film can be cut before the actual extrusion of the tube into corresponding pieces of film, preferably in the form of strips, wherein the strips z. B. may have a width of typically 15 mm.

After the manufacture of the tube according to the invention 10 can do that with the pipe 10 form-fitting connected piece of film 16 with an identification laser, preferably excimer laser, are exposed, wherein laser-sensitive materials, for. B. irreversible change in the form of laser-sensitive pigments and a corresponding permanent labeling, z. B. with plain text and / or barcode.

10

pipe

12

extrusion device

14

pipe section

15

Exterior wall area

16

foil piece

18

roller

20

backing

Claims (8)

Method for producing a tubular hollow body, in particular a tube ( 10 ) of polymer material having at least one film piece which can be marked under the action of laser radiation (US Pat. 16 ), wherein the film piece ( 16 ) has at least one laser-sensitive material, wherein at least a portion of the film piece ( 16 ) with the outer wall of the tube ( 10 ) is materially connected, and wherein the film piece ( 16 ) is at least partially convertible to a molten state by heating from a dimensionally stable state, wherein in the method the tube ( 10 ) is formed by extrusion, and wherein in a first step during the extrusion of the tube ( 10 ) the at least one piece of film ( 16 ) in the dimensionally stable state at least partially on an outer wall region ( 15 ) of an already extruded pipe section ( 14 ) of the pipe ( 10 ) is applied, wherein after application at least the portion of the film piece ( 16 ) a surface contact with the outer wall area ( 15 ), and wherein in a second step during the extrusion of the tube ( 10 ) the piece of film ( 16 ) is heated to at least partially in a molten state, and wherein in a third step, the film piece ( 16 ) is cooled to at least the partial area cohesively with the outer wall area ( 15 ) connect to. A method according to claim 1, characterized in that in the first step substantially the entire film piece ( 16 ) on the outer wall area ( 15 ) is applied, wherein after application substantially the entire film piece ( 16 ) a surface contact with the outer wall area ( 15 ) having. Method according to claim 1 or 2, characterized in that a piece of film ( 16 ), which consists of a mixture of a polymeric material and the at least one laser-sensitive material. Method according to one of the preceding claims, characterized in that the film piece ( 16 ) by means of a heated contact pressure means ( 18 ) at least partially on the outer wall area ( 15 ) is pressed. Method according to claim 4, characterized in that a heated roll ( 18 ) as a pressing agent ( 18 ) is used. Method according to claim 4 or 5, characterized in that a piece of film ( 16 ) used with a carrier layer ( 20 ) is releasably connected from polymer material, wherein the polymer material of the carrier layer ( 20 ) has a melting temperature which is greater than a maximum heating temperature to which the film piece ( 16 ) is heated to the film piece ( 16 ) at least partially in the molten state, wherein the pressing means ( 18 ) with the carrier layer ( 20 ) is brought into contact with the film piece ( 16 ) at least partially on the outer wall area ( 15 ), and wherein the carrier layer ( 20 ) after forming the integral connection of the film piece ( 16 ) is separated. Method according to one of the preceding claims, characterized in that a piece of film ( 16 ) is used which has at least one RFID transponder. A method according to claim 7, characterized in that the RFID transponder in the film piece ( 16 ) or as a printed circuit on the film piece ( 16 ) is printed.