DE3744261A1 - Process for producing a packaging tube and apparatus for carrying out the process - Google Patents

Abstract

In a process for producing a packaging tube (21) from a printed film web (16), the longitudinal edges of the film web are arranged, overlapping one another and frictionally connected, in front of a tube winding-up roller (25). Environmentally friendly polypropylene is used as the film material and, before connecting, at least one of the longitudinal edges of the film web is coated with liquid contact adhesive (14) in a simple and accurate way in a rotogravure printing unit (1). In an apparatus for carrying out the process, a tube former (7) is arranged between a gravure printing unit (4) on the outlet side of a rotogravure printing machine and the tube winding-up roller (25), and the gravure printing unit (1) serving for coating the film web (16) with adhesive is one of at least two gravure printing units of the rotogravure printing machine. <IMAGE>

Description

The invention relates to a method for manufacturing make a packaging tube from a print stretch, heat-shrinkable film sheet made of art fabric in a continuous pass, in which the longitudinal edges of the film web in front of a hose reel arranged overlapping one another and non-positively ver be bound, and a device for performing of the procedure.

In a known method of this type, the in a rotogravure printing machine and printed on one Take-up roll wound film web from the prints delivered to a hose manufacturer where the foils then run in a tube former to a tube shaped and ver along its edges using ultrasound welded and wound up on a hose reel is wrapped. The hose former contains guide rollers, through which the longitudinal edges of the film web are guided that they overlap. That overlap the longitudinal edges of the guideway are in an ultra Sonic welding machine welded. The material of the foils membrane is polyvinyl chloride, which easily welds leaves. Then the hose is placed on the hose Take-up roll wound up. The hose will then products to be packaged to the respective manufacturer, such as liquids, spreadable fats and the like, gelie  finished. There are shorter sections of the hose according to the length of the respective packaging, such as cans or bottles, cut and tailored to the ver pack, e.g. Bottle or can, shrunk on. On this way the packaging receives the desired one mostly multi-colored print.

Ultrasonic welding of the longitudinal edges is expensive not only because it is substantial Requires energy and an expensive welding machine, but also because the one tool part in the preformed hose must lie, which is because of the Space requirements for smaller hose diameters Difficulties arise and the approach is complex lead the longitudinal edges to be welded exactly between the tool parts and around the one tool part on the other part of the tool (the sonotrode) facing side requires.

Also printing on the film web in a printing house and the further processing of the printed film web with a hose manufacturer is complex.

The invention has for its object a method of the generic type and a device for through to specify the procedure in which the manufacture of the hose is easier.

According to the invention this object is achieved in that at least one of the longitudinal edges of the film web connecting, in a rotary printing unit with liquid Adhesive is coated, the trough of the Printing unit loaded with the adhesive instead of color becomes.  

Difficulties like welding the longitudinal edges of the film web for hose formation occur can be avoided by gluing because here with the longitudinal edges of the film web only for mutual Brought overlap, but no exact location relative have to have a tool part. Still can gluing in the area of the longitudinal edges of the film web be done very precisely because of the application of the adhesive precise dosing and tight using a printing unit Limiting the adhesive allows, similar to that Printing using color.

A rotary printing unit is preferably used as the rotary printing unit. Gravure printing unit used. A rotogravure printing unit enables particularly precise dosing and limitation of the adhesive. All that is needed is the forme cylinder rotogravure of the rotogravure with one over its circumference the engraving of cells to hold the adhesive correspond to the desired width of the adhesive seam width to be provided, with excess Adhesive when applied by gravure printing standard scraper knife, the so-called doctor blade, completely removed from the surface of the forme cylinder can be.

The polyvinyl chloride previously used as a film web is an easy to process material, but not environmentally friendly as it doesn't naturally is buildable and releases hydrochloric acid when burned becomes.

It is therefore advantageous if polypropy is used as the film material len or a similarly more environmentally friendly Plastic is used. Polypropylene is easy to use remove by incineration, without causing environmental damage Residues arise so that the Ver packaging containers such as cans, glasses or bottles and the like, or the material of these containers again  can be used. Similar plastics are included for example polyethylene, polyester and the like.

A contact adhesive can then be used as the adhesive will. Here you come with low pressure for gluing the coated longitudinal edges of the foils track out.

In particular, the pressure force for gluing the Longitudinal edges of the film web from the tensile force of the Hose take-up reel can be derived. this has the advantage that a pressure device for pressing the longitudinal edges of the film web to be glued are eliminated can.

The film web can easily be deflected area whose width is smaller than that of the film web is being pulled around in the direction of travel, that the longitudinal edges of the film web after leaving the deflection surface corresponding to the width of the adhesive overlap coating.

The inventive device for performing the Process with a tube former stands out by from that the hose former between one from aisle-side printing unit of a rotary printing press and the hose reel is arranged and that of Coating the film web with adhesive serving printing one of at least two Rota gravure printing plants tion printing press. The printing can and forming the film web into a tube in one continuous operation already in the print shop take place, the tube former immediately can connect to the rotary printing press and the rotary printing press with only one additional union printing unit and a corresponding forme cylinder  needs to be provided if this press not a sufficient number of printing units has, as is often the case for multi-color printing are required. The tube former can be very simple be designed, in particular the winding and unwinding the film web before tube forming and the trans port to and from the tube forming unit is eliminated.

A particularly simple device for carrying out the method can consist in that the deflecting surface the top of one in the running direction of the film web extending guide tongue with one for flat, non shaped film sheet bent or arched above th beginning section, the width of a value, which is slightly smaller than the width of the film web, down to a value in the running direction of the film web takes, the smaller, about 5 to 25%, preferably about 15% than the width of the flattened hose and has an end section whose width is up to increases approximately to the width of the flattened tube, and that the longitudinal edges of the film web around the longitudinal edges of the leading portion of the guide tongue around the Underside of the guide tongue. Here the adhesive-coated film web can easily over and over the top of the guideway Underside with mutual overlap of the longitudinal edges of the film are pulled.

Alternatively, the deflection surface can be covered by part of the Be formed circumferential surface of a deflecting cylinder, the axial length less than the width of the film web is. Training is also very easy.

If the deflection cylinder is rotatably supported, results there is very little wear on the film web.  

If the tractive force exerted on the film web exceeds the hose reel is applied, is omitted an additional device for exerting traction.

At the bottom of the beginning section of the guide tongue can be through one perpendicular to the plane of the Guide tongue standing guide wall separate Blattfe apply under tension. These leaf springs ge ensure greater security for guiding around the longitudinal edges of the film web around the longitudinal edges of the Guide tongue, while between the leaf springs standing guide wall a premature overlap of the Longitudinal edges of the film web prevented.

Instead of the leaf springs or in addition to the leaf springs can on the the longitudinal edges of the film web facing side of the guide tongue two rotary bur be arranged most, the axes of rotation about in Laufrich tion of the film web are directed and each on a Side of the longitudinal center line of the guide tongue, whereby the direction of rotation of the rotary brushes is chosen is that the material of the film web overlaps the longitudinal edges of the film web are brushed. These rotary brushes also contribute to the fact that the longitudinal edges of the film web on the underside of the guide tongue overlap or sufficiently far over rag.

The invention and its developments are next Based on the drawing of a preferred embodiment described in more detail, for example. Show it:

Fig. 1 is a side view of a Prior inventive device for manufacturing a packaging Sly ches of a printed sheet,

Fig. 2 is a rear view of a tube former provided as in the inventive device Füh approximately tongue with a therearound guided to the tube forming film web,

Fig. 3 is a rear view of the guide tongue of FIG. 2 alone,

Fig. 4 is a side view of the application of adhesives material according to the inventive method before seen form cylinder of a rotogravure printing unit,

Fig. 5 is a side view of another embodiment of a guide tongue according to the invention,

Fig. 6 is a front view of the guide tongue of FIG. 5,

Fig. 7 is a side view of a third embodiment of a hose former according to the invention with a deflecting cylinder and

Fig. 8 is a view of the tube former of FIG. 7 seen in the direction of arrow P.

The device shown in Fig. 1 for producing a packaging tube from a printed, stretchable and heat-shrinkable film web made of plastic consists of a schematically illustrated rotogravure machine with several successive gravure printing units 1 , 2 , 3 and 4 , an unwinding roll 5 , one Cutting unit 6 and a hose former 7 .

Each gravure printing unit contains, in a manner known per se, an ink fountain 8 (also called “ink fountain”), a forme cylinder 9 with a doctor blade 10 , an intermediate rubber roller 11 , which is pressed against the forme cylinder 9 by a pressure roller (not shown) (the “impression roller”) , At least one deflection roller 12 and a Trockeneinrich device 13 with a drying drum, not shown.

The ink wells 8 of the rotogravure printing units 1 and 2 do not contain ink, but rather by means of a volatile solution such as toluene, dissolved contact adhesive 14 (commercially available from AGS Chemie GmbH, Feldstrasse 3-45, D-6053 Obertshausen 2 , under type No. 7104), which is a mixture of polychloroprene and synthetic resins, while the ink wells 8 of the gravure printing units 3 and 4 contain color 15 in the usual manner.

From the unwind roll or supply roll 5 , a wider sheet 16 of polypropylene is unwound and roll 17, one after the other, is passed through all rotogravure printing presses 1 to 4 via a turning device contained in the first gravure printing unit 1 . The film web 16 is coated by the gravure printing unit 1 on one side and by the gravure printing unit 2 on its other side in the longitudinal direction with several parallel, in the longitudinal direction of the film web 16 narrow adhesive strips, the adhesive strips on one side of the Film web 16 are laterally offset from the adhesive strips on the other side of the film web by about the width of an adhesive strip and the film web on one side near its one longitudinal edge and on the other side near its other longitudinal edge, each with one of the adhesive strips is provided.

In the following gravure printing units 3 and 4 , different colors are then successively printed on one side of the film web 16 .

In the cutting unit 6 , the film web 16 is cut into several adjacent, narrower film webs 16 a , which are passed over deflection rollers 18 , 19 into the tube former 7 . The cutting of the wider film web 16 into the narrower film webs 16 a takes place between two approximately one width of adhesive strip offset on both sides of the film web 16 against opposite adhesive strips, so that each narrower film web 16 a is provided with two adhesive strips, on top of the Film web 16 a along one longitudinal edge and on the underside of the film web 16 a along the other longitudinal edge.

Alternatively, it is also possible to use the middle adhesive brush up on the later cut edges wear, alternately on one and the other Ren side of the film web.

The tube former 7 includes each of the narrower foil webs 16 a its own guide tongue 20 (of which in the view according to Fig. 1 only one is visible) made of a thin sheet metal or plastic with a previously bent initial portion 20 a and a straight end portion 20 b, the top of which forms a deflection surface for the film web 16 a in question. The initial section 20 a has two bends of the sheet and takes, as the bottom view of one of the guide tongues 20 in FIGS . 2 and 3, from the beginning or end of the end in the running direction of the film web 16 a of a value that is about twice the width of the adhesive strip is smaller than the width of the narrower film web 16 a , in the running direction of the film web 16 a down to a value which is approximately equal to the width of the flattened hose 21 emerging from the hose former 7 . Here, the width is reduced symmetrically on both sides of the longitudinal center line of the guide tongue 20 . In contrast, the width of the end portion 20 b of the guide tongue 20 increases towards the outlet end up to approximately the width of the flattened hose 21 . On the concave, in Fig. 1 lower side of the guide tongue 20 of the guide tongue 22 is attached along a guide wall 20 of the longitudinal center line of the guide tongue 20 perpendicular to the plane. On each side of the guide wall 22 , a leaf spring 23 a , 23 b arched in the same direction as the guide tongue 20 is fastened with one end, while its other end abuts the underside of the end section 20 b .

At the outlet end of the guide tongue 20 , a deflection roller 24 common to all tubes 21 is provided, around which each tube 21 is passed to a winding roller 25 .

In the tube forming the guide in question will track 16 a with its longitudinal edges to the longitudinal edges of the top portion 20 a of the respective guide tongue 20 around Zvi on the concave side of the guide tongue 20 rule of the guide tab 20 and the leaf springs 23 a, 23 b pulled, the pulling force is exerted on the hose reel 25 concerned by the drive thereof. All hose winding rollers 25 are driven by a common drive. In the area of the end portion 20 b overlap the longitudinal edges of the film web 16 a , as shown in Fig. 2. The deflecting around the deflection roller 24 vertically on the plane of the hose 21 and thus on the overlapping edges component of the exerted on the winding by the hose winding roller 25 in the longitudinal direction of the hose 21 is sufficient to the in the area of to overlap the overlapping edges of the film web 16 a lying contact adhesive strips. In addition, a further, radially directed to the circumference of the hose winding roller 25 pressure force is exerted on the overlapping edges, while the hose 21 is wound on the hose winding roller 25 . This pressure force is particularly high in the area of the overlapping longitudinal edges of the film web 16 a , because in this area the tube is 50% thicker than in the adjacent tube areas. If the hose is therefore arranged on the winding roll 25 so that the hose is wound without deflection tangentially to the hose winding reel 25 21, the guide roller 24 may also be omitted.

Fig. 4 shows a side view of a forme cylinder 9 , as is provided in one of the gravure printing units 1 and 2 used for applying the contact adhesive. Such a form cylinder 9 is over its circumference with several ren in its surface engraved tracks provided 26 of well-like indentations, the distances in the axial direction of the forme cylinder 9 is approximately equal to the width of the narrower webs of film 16 a. The forme cylinder 9 receives the liquid contact adhesive 14 in the well-like depressions of the tracks 26 , while the excess contact adhesive 14 is scraped off by the associated doctor blade 10 .

The corresponding tracks 26 on the surface of the forme cylinder 9 of the other intaglio printing unit used to apply adhesive 14 are offset by approximately the width of one track 26 from those of the first forme cylinder 9 . When applying the adhesive 14 on the wider web of film 16 are therefore on one side of the film web 16 adhesive strip with a width and spacing of the traces 26 corresponding width and position and on the other side of the foil web through the other plate cylinder 9 in a 16 to Traces on the other forme cylinder 9 corresponding width and position, but with respect to the contact adhesive strips on one side of the film web 16 approximately offset by the width of the tracks 26 layer.

FIGS. 5 and 6 show a modified guide tongue 20 'in which the section 20' is a continuously curved and the leaf springs 23 a, 23 b are omitted. The partition 22 'is also largely adapted to the curvature of the guide tongue 20 '.

FIGS. 7 and 8 show a further modification of the tube former 7, wherein the deflection for the respective film web 16 of an inverting cylinder 28 is formed a through part, about a quarter, of the circumferential surface, which is rotatably mounted about an axis 29. The axial length of the deflecting cylinder 28 is less than the width of the film web 16 a . The axial length of the deflection cylinder 28 is preferably only about half the width of the film web. The film web 16 a is deflected adjacent to the deflecting surface of the deflecting cylinder 28 and thereby passed with its longitudinal edges past the flat end faces of the deflecting cylinder, the longitudinal edges of the film web 16 a after passing by the deflecting cylinder 28 to the side facing the deflecting cylinder 28 (here the Underside) of the film web 16 a are pulled until they overlap each other in the width of the adhesive strips, as shown by the broken lines in the lower half of FIG. 8. The running direction of the film web 16 is indicated by an arrow next to the hose 21 formed by the film web 16 a . In this embodiment, the friction between the film web 16 a and the deflection surface is eliminated.

Further modifications are also possible. Thus, in the embodiment according to Figures 1 to 4, the leaf springs 23 a, 23 b also omitted, and alternatively -. Or in addition to - on the provided rotary brush 27, the overlapping longitudinal edges of the film web 16 a receiving side of the guide tongue 20 be, in the vicinity of the beginning of the overlap of the longitudinal edges of the film web 16 a , so that the axes of rotation of the rotary brushes 27 on both sides and parallel, as shown, or somewhat oblique to the longitudinal center line of the guide tongue 20 . The direction of rotation of the Rota tions Brush 27 is chosen such that the material of the film web 16 is a a back brushed to the overlapping longitudinal edges of the web of film 16 around which guide the film web support 16 a to the guide tongue 20 to be.

Furthermore, instead of the gravure printing unit 2 , one of the gravure printing units 3 and 4 can also be used to apply the contact adhesive. The drying device 13 of the first intaglio printing unit 1 , which is used to apply adhesive, can be omitted if the distance of the last deflecting roller 12 of the first intaglio printing unit 1 from the entrance of the following intaglio printing unit 2 is sufficiently large and / or the running speed of the film web 16 is selected such that that the liquid contact adhesive has sufficient time to flash off during the passage of this distance. The drying device 13 of that of the gravure printing units 2 , 3 and 4 , which is used to coat the other side of the film web 16 with adhesive, can be omitted if the position between the forme cylinder 9 and the guide roller 12 of this gravure printing unit or the running speed of the film web 16 is chosen so that the adhesive can vent during the passage of this distance.

Then it is possible to coat only one longitudinal edge of the film web 16 on one side with contact adhesive material if a single contact adhesive strip is sufficient to bond the two longitudinal edges of the film web to one another.

Instead of polypropylene, polyethylene, polyester or a similar environmentally friendly, especially without Acid formation combustible plastic can be used. In principle, PVC could also be used if accepted its lower environmental impact can be.

Instead of two or three, printing with color serving gravure printing units can also have a different number of gravure printing units, depending on the desired input or Multi-color printing can be used. Alternatively, too an offset or flexographic printing machine can be provided.

The hose take-up roll can be in a known manner Be stored so that they are "flying" interchangeable is, so that the operation of the printing press is not needs to be held.

Claims (13)

1. A method for producing a packaging tube from a printed, stretchable and heat-shrinkable plastic film web in a continuous through-run, in which the longitudinal edges of the film web are arranged overlapping each other and non-positively connected in front of a hose winding roll, characterized in that at least one of the Longitudinal edges of the film web ( 16 a ), before being connected, are coated in a rotary printing unit ( 1 ) with liquid adhesive ( 14 ), the ink well ( 8 ) of the printing unit ( 1 ) being coated with the adhesive ( 14 ) instead of with color is loaded. 2. The method according to claim 1, characterized in that a rotary gravure printing unit ( 1 ) is used as a rotary printing unit. 3. The method according to claim 1 or 2, characterized net that as a film material polypropylene or a similarly environmentally friendly plastic is used. 4. The method according to any one of claims 1 to 3, characterized characterized in that a contact adhesive as an adhesive fabric is used.   5. The method according to any one of claims 1 to 4, characterized in that the pressure force for gluing the longitudinal edges of the film web ( 16 a ) is derived from the tensile force of the hose winding roll ( 25 ). 6. The method according to any one of claims 1 to 5, characterized characterized in that the film web around a deflection area whose width is smaller than that of the film web is pulled around in the direction of travel, that the longitudinal edges of the film web after leaving the deflection surface corresponding to the width of the adhesive overlap the fabric coating. 7. Device for performing the method according to one of claims 1 to 6, with a tube former, characterized in that the tube former ( 7 ) between an output-side printing unit ( 4 ) of a rotary printing press ( 1-5 ) and the tube winding roll ( 25 ) and the printing unit ( 1 ; 2 ) used to coat the film web ( 16 a ) with adhesive ( 14 ) is one of at least two printing units of the rotary printing press ( 1-5 ). 8. The device for performing the method according to claim 6, characterized in that the deflecting surface the top of a in the direction of the film web ( 16 a ) extending guide tongue ( 20 ; 20 ') with a flat, undeformed film web ( 16 a ) Above kinked or arched beginning section ( 20 ; 20 a ), the width of which decreases from a value which is slightly less than the width of the film web in the running direction of the film web to a value which is smaller, approximately 5 to 25%, preferably about 15% than the width of the flattened tube ( 21 ), and with an end section ( 20 b ; 20 ' b ), the width of which increases up to about the width of the flattened tube ( 21 ), and that the longitudinal edges of the film web ( 16 a ) around the longitudinal edges of the start section ( 20 ; 20 a ) of the guide tongue ( 20 ; 20 ') around the underside of the guide tongue ( 20 ; 20 ') are pulled. 9. A device for performing the method according to claim 6, characterized in that the deflecting surface is formed by part of the peripheral surface of a deflecting cylinder ( 28 ), the axial length of which is less than the width of the film web. 10. The device according to claim 9, characterized in that the deflecting cylinder ( 28 ) is rotatably mounted. 11. Device according to one of claims 7 to 10, characterized in that the tensile force exerted on the film web ( 16 a ) is applied over the hose reel ( 25 ). 12. The apparatus according to claim 8, characterized in that on the underside of the starting portion ( 20 a ; 20 ' a ) of the guide tongue ( 20 ; 20 ') two through a perpendicular to the plane of the guide tongue ( 20 ; 20 ') standing guide wall ( 22nd ; 22 ') separate leaf springs ( 23 a ; 23 b ) bear under tension. 13. The apparatus of claim 8 or 12, characterized in that on the longitudinal edges of the film web ( 16 a ) facing side of the guide tongue ( 20 ; 20 ') two rotary brushes ( 27 ) are arranged, the axes of rotation approximately in the direction of rotation the film web ( 16 a ) are directed and are each on one side of the longitudinal center line of the guide tongue ( 20 ; 20 '), and that the direction of rotation of the rotary brushes ( 27 ) is selected so that the material of the film web ( 16 a ) is brushed towards the overlapping longitudinal edges of the film web.