DE19743657C2 - Label section - Google Patents

Description

The invention relates to a label section from a for example, stretchable plastic film, which in particular for labeling a plastic container made of PET, PEN or PC is suitable.

DE 196 12 027 C1 describes a method for wrap-around Label cylindrical or prismatic containers known in which a made of a plastic film Label section in a pre-stretched condition around the loading is placed and glued into a ring. With the retar The stretch of the label section attaches itself to the stretch the outside of the container.

Such a label section has proven itself; Indeed is the adhesive force of a known section of label not sufficient for those plastic containers that one Have thin walls and carbonated drinks and the like are filled, an extension of the order catch of the container due to a high internal pressure in the container effect after filling. With emptying, but also with the cooling of the container, the container internal pressure is reduced adorns, so that the circumference of the container on an original reduced dimension. If there are no reserves for further  Shrinkage present on the pre-stretched label section are, this detaches from the container wall, so that it the further handling of the container to strip the Label section is coming.

Also, when using label sections made of plastic sheeting difficulties with the machine nellen processing of the film web occur because it is a Adhesion of the film web to metal surfaces of the machines comes. Due to the capillary action of a narrow air gap between a smooth metal surface and one that is also smooth th, air-impermeable and fast-running film web the film web is attracted to the metal surface. Depending on The type of plastic used is electrostatic Charging of the film web possible, which the adhesion of the film reinforced on a metal surface.

Such as B. known from two superimposed glass panes, can due to the low surface roughness Form contacting surfaces adhesive bonds, whereby there are disruptions in the automated production process, such as the Tear the film web, can come.

So there is the task of label sections and egg NEN labeled container, through which the state of the Technology increased adhesion of the label section to the Container wall and improved mechanical handling possibility is effected.

This task is firstly a label section solved according to the preamble of claim 1, which thereby ge indicates that the surface of the adhesive side of the Eti chain section is at least partially relief.  

With "sticky side" here is the side of the label section meant that is inside the finished labeled container, d. H. which contacts the outside of the container and due to Frictional forces and / or by gluing to the container is liable on the outside.

The roughened depth of the foil is due to the relief surface web and thus the adhesive surface of the label sections we considerably increased. The relief is composed repetitive arrangements of raised relief elements and recesses in between. It is essential cher advantage of the invention that by the raised relief elements on the adhesive side of the label section is created by the fact that when gluing the relief elements are compressed and moved. With the Shrinking the container will expand the relief elements, the Following the container wall, causing detachment of the adhesive side of the label section from the container wall and thus egg interruption of the adhesive layer is prevented.

Failure of the entire adhesive layer by peeling, the starts from a damaged area, for example where the adhesive bonds by infiltrating the adhesive layer with moisture can be destroyed by the relief Surface can also be prevented. An incipient crack in the adhesive layer ends at the next depression and can initially do not reproduce. The extreme Kerbwir A crack in the adhesive layer is caused by the recess Foundations weakened significantly. For example wise through the use of force, e.g. B. when compressing the Plastic container, yet to break the adhesive layer com men, is characterized by the relief surface of the adhesive side of the Section of the label stripping the label from the container difficult.  

Due to the multitude of individual contact points of the sublime Relief elements of the label section with the outer container wall, the "stick-slip effect" can be enhanced, d. H., that initially a high static friction in an interface over must be sore before it is due to the generally lower Sliding friction can slip.

It is also advantageous that in the wells of the Surface reliefs of the label section at Ver working of the plastic film webs or the resultant presented label sections according to the invention, in particular through high-speed packaging machines, air cushions can form an adhesion of the sheet-like structures prevent smooth surfaces of the machines. Through the air pole The direct contact between film and machine parts becomes the most largely prevented, and the possibly occurring electro static electricity is minimized.

It is particularly favorable for machine processing, the surface relief by parallel to each other To form grooves. This extends over the label width stretching grooves allow in addition to the aforementioned advantages len that existing gas pores in the adhesive layer with the An pressing the label to the edges of the label.

In an advantageous embodiment, the Grooves towards a development of a circumference of one labeling area of the container. After sticking the The label section, the grooves are then parallel to the um catch the container so that several rings of relief Contact the outside of the container with the surface of the adhesive side, being perpendicular to the vertical axis of the container, the represents the direction of a possible wiping. The Ab A maximum resistance will graze through optimal static friction  between the container wall and the adhesive side of the label cut opposite.

Distance and width of the grooves, based on the given Size of a label section, determine their number. The These parameters depend on the degree of the expected Shrinkage of the plastic container, as well as after the viscose a possible adhesive to be applied, the Ril len preferably a distance of 0.01 to 0.02 mm and a Have a width of 10 µm to 1 mm, defined by the width of the unrelief area between two grooves.

It is also possible that the relief from net or wa ben-like, intersecting elevations or depressions stands. Such a structure is advantageous if the Degassing of the adhesive layer should be improved by a The gases escape in two directions at the label section is possible. Especially with embossed labels cuts in which the printed side is also embossed has such a surface relief from aesthetics reasons are more appealing than those with uniaxial trending grooves.

To the advantages of a pronounced upper described above to be able to use surface relief effectively, it is favorable that the surface relief has a roughness of 0.5 to 5 µm.

It is over for a label section according to the invention economic reasons advantageous that its film mat rial from a polyolefin, in particular from polyethylene, Po lypropylene or from a mixture or copolymer of this Polyolefins exist because these standard plastics in ver packaging industry are widespread. They are also polyolefins  physiologically harmless, so that a contact derar materials with food is harmless.

Stretch films in particular are made of elastic mate rialien, preferably from styrene-butadiene block copolymers.

The thickness of the surface with at least one relief provided film material for the production of a label cut is 25 to 100 µm.

The invention creates a labeled container fen, where the label section from a plastic film which consists of stripping the label section tes aggravating relief of the adhesive side is provided.

The invention is illustrated by an embodiment explained. The figures in the drawing show:

Fig. 1a, b shows an enlarged detail of a Etikettenab-section in perspective view of the front of front and back sides,

FIG. 2a, b a glued label portion of a plastic container in schematic Schnittdarstel lung.

Embossing roller can be tempered so that the finished label ten film web, e.g. B. before winding, by thermoforming is shaped.

The invention further relates to a method for wrapping Around labeling of cylindrical or prismatic Be keep with a label section according to the invention, the is characterized in that the surface of the adhesive side of the label section is at least partially embossed.

Here the label section is maximally up to the limit reversibility and immediately before application the label section on the outside of the container stretches. The pre-stretched label section is over with itself lapping label section edges around the container Placed outside and the gluing process by reaction and / or heating initiated.

The invention creates a labeled container fen, where the label section from a plastic film which consists of stripping the label section tes aggravating relief of the adhesive side is provided.

The invention is illustrated by an embodiment explained. The figures in the drawing show:

Fig. 1a, b shows an enlarged detail of a Etikettenab-section in perspective view of the front of front and back sides,

FIG. 2a, b a glued label portion of a plastic container in schematic Schnittdar position.

A section of a label section 10 is shown in FIG. 1a. The label section 10 consists of a plastic film 4 , which is partially provided with prints 3 on a printed side 5. The film is produced as a slit film or as a tubular film, as is known in the prior art.

The back of the label section 10 shown in FIG. 1b forms the adhesive side 1 . It is in a label section 10 according to the invention with mutually parallel grooves 2 or differently shaped depressions, which can be embossed or molded. A ridge 6 or another raised relief element is located between two grooves.

To achieve this relief of the surface, a printed or unprinted film web by a pair of rollers drawn, at least one of which has an engraved surface which embossed the relief into the film. Especially fine reliefs can be achieved by thermoforming, whereby the film up to the softening temperature of the plastic is heated. Temperature-controlled embossing rollers can be used for this be set. Profiled lips of the extruder die set Another option, a structured label film to create.

It is also conceivable for wide-slit films, one of the Ex truder downstream rolls ("chill rolls") accordingly to engrave and simultaneously with the cooling of the extru dated foil web to impress the relief, which means none additional energy for heating a downstream embossing roller must be applied. Even the finished printed can and coated film web or the already cut Eti chain section pulled through a pair of engraved rollers become.  

When embossing by rolling is any surface relief possible, which is due to the complementary Gra is determined by the embossing roller.

However, it is also possible to arrange shaping tools in such a way that groove-shaped relief elements 2 form in the pull-off direction of the film web. A label section 10 according to the invention can be produced in that a previously finished film web is coated with a further melt layer made of plastic. The coating can then be formed, for example, using a doctor blade which has a cut that is complementary to the desired profile shape.

Fig. 2a shows in section a container wall 12 of a closed plastic container 20 , which is filled with a liquid 15 containing kohlensäu. Due to an increase in temperature, the solubility of carbon dioxide in the liquid decreases and carbon dioxide from the solution passes into the gas phase. It increases the indicated by the arrows 14 , 14 'internal pressure in the container, which spreads on all sides and acts on the inside 13 of the container wall 12 . Due to the small modulus of elasticity of the plastic material of the container, these forces cause an expansion of the circumference from a diameter D _{0 of} the container in the production state to a diameter D ₁ in the filled state.

A label section 10 is connected to the outside 11 of the container wall 12 via an adhesive layer 16 . The ridges 6 of the relief surface of the adhesive side 1 have been compressed by the shrunk ring formed from a label section 10 and exert a force on the outside of the container 11 due to springback.

As the pressure in the container drops, the expanded scope of the container returns to its original size. A ring formed from known film material does not follow the shrinkage, so that it comes to th detachment and stripping of the label section in known label sections. A label section 10 according to the invention, however, has a reserve for the same in the radial direction due to its underside 1 in relief. The previously compressed ridges 6 of the surface relief expand and follow the shrinking motion of the container.

A beginning at a label edge 7 breakage of a possibly additionally applied adhesive layer between a container outer side 11 and a ridge 6 'on a profiled adhesive side 1 of a label section 10 is first stopped at an adjacent groove 2 '.

If there is detachment of the label section 10 from the container outer side 11 , the profiled surface of the adhesive side 1 contacts the container outer side via a multiplicity of contact points 8 , 8 'on the ridges 6 , 6 '. Due to the friction in the boundary layer between the outside of the container 11 and contact points 8 , 8 ', the label section 10 is held in the region 20 provided on the container.

The invention makes it possible to use plastic containers To put labels on after using the container are easy to remove, so that multiple use of the Container is possible. Through the surface relief of the detention The label remains on the side during handling Transport and sale at the container, even without a clover exercise or even if it is broken.

With the labeled container according to the invention is one Packaging has been created for products that meet the requirements of an appealing product presentation and a safe product labeling fulfilled.

Claims (9)

1. Label section made of a plastic film, in particular for labeling a plastic container made of PET, PEN or PC, characterized in that the surface of the adhesive side ( 1 ) of the label section ( 10 ) is at least partially embossed. 2. label section ( 10 ) according to claim 1, characterized in that the plastic film is expandable. 3. label section ( 10 ) according to claim 1 or 2, characterized in that the surface relief of mutually parallel grooves ( 2 ) is formed. 4. label section ( 10 ) according to claim 3, characterized in that the grooves ( 2 ) extend in the direction of a development from a circumference of a region of the container to be labeled. 5. label section ( 10 ) according to at least one of Ansprü che 2 to 4, characterized in that the width of the unrelief area between two grooves, ie the distance between the grooves ( 2 ) to each other, 0.01 to 0.2 mm BE. 6. label section ( 10 ) according to at least one of Ansprü che 1 to 5, characterized in that the grooves ( 2 ) have a width of 10 microns to 1 mm. 7. label section ( 10 ) according to claim 1, characterized in that the relief consists of mesh or honeycomb intersecting elevations or depressions. 8. label section ( 10 ) according to at least one of Ansprü che 1 to 7, characterized in that the surface structure has a surface roughness of 0.5 to 5 microns. 9. Labeled container, characterized in that the label section ( 10 ) from a plastic film ( 4 ) be, which is provided with a stripping of the label section ( 10 ) complicating surface structure of the adhesive side ( 1 ).