WO2016128521A1

WO2016128521A1 - Method for producing a container from plastic, container, and label element

Info

Publication number: WO2016128521A1
Application number: PCT/EP2016/052932
Authority: WO
Inventors: Guido Pöhls
Original assignee: Knauer Holding Gmbh & Co.Kg
Priority date: 2015-02-13
Filing date: 2016-02-11
Publication date: 2016-08-18
Also published as: DE102015102097A1

Abstract

The invention relates to a method for producing a container (1) from plastic according to an IML process, to a container (1) composed of plastic, and to a label element (4), wherein the label element (4) has grooves (11) on the side facing the wall of the container (1), the course and cross-section of which grooves are selected in such a way that the grooves (11) are suitable as flow aids for directing the plastic melt during the injection-molding process.

Description

Method for producing a container made of plastic, container and label element

The invention relates to a method for producing a container made of plastic according to an in-mold labeling (IML) method, in which a label element in a

Injection mold is inserted such that the label element covers at least a portion of a wall of the container to be generated, the plastic melt is injected at a gate, and along the wall of the container forming surface of the injection mold is guided so that the container is formed, wherein the label element is back-injected and connected to the wall of the container ^¬ nisse.

Furthermore, the invention relates to a container made of plastic with a wall and a label element, which is produced by an IML method such that at least a portion of the wall of the container is covered and connected to the label element and a label element for Use in an IML process for manufacturing such a container.

Such a method, such a container and a label element are known from DE 10 2005 045 621 AI.

Such containers are used in particular for receiving food. The IML method allows the labeling of the container during the Herstellungspro ^¬ process.

From DE 10 2012 103 082 AI are also prepared according to such an IML-container container and a label element, which by means of the IML method with the Container is known. According to this document, defined flow aids are used in the IML process, with which the plastic melt can be specifically directed. For this purpose, tubular depressions are formed in the injection mold, which is used to produce the container. During the IML process, this will be when the plastic melt fills the mold also with art ^¬ material filled. In this case, bead-like thickenings or ribs are formed on the wall of the container. The flow aids cause the case of containers with a very small wall thickness that the liquefied plastic retain flowable during Spritzgussver ^¬ driving. The shape, cross section and the course of the flow aids can be selected for given process parameters so that an optimal filling of the injection mold with the plastic melt is achieved. It can be such a premature solidification of the melt or a

Flowing back the liquid plastic from the top

Cup edge can be prevented behind the label elements. With this method, very thin-walled containers can be produced in good quality.

In view of this prior art, the invention has for its object to provide a method for producing a container made of plastic according to an IML method and a container made of plastic with a label element, in which further costs can be saved and another quality improvement of the container. This object is achieved by a generic method ^¬ ge, wherein the label member has on the side facing the wall of the container side grooves whose course, shape and cross-section are chosen so that the grooves during the IML process fill with plastic, so that form in the grooves flow aids through which the plastic melt is targeted in the area of the label element.

Furthermore, the object is achieved by a generic container, wherein the label member has on the side facing the wall of the container side grooves, which are filled with synthetic ^¬ material, said history, shape and cross section of the grooves are chosen so that fill the grooves with plastic during the IML process, so that flow aids develop in the grooves, by means of which the plastic melt in the area of the label element is specifically directed.

Further, the object is achieved by a label element, which has grooves on one side, the course, shape and cross-section are chosen so that the grooves can fill with plastic during the IML process, so that form in the grooves flow aids , by means of which the plastic melt in the area of the label element can be specifically steered.

According to the method of the invention, the container according to the invention and the label element according to the invention, the flow aids desired for the production of the container are formed in the label element. If currency ^¬ rend of the IML process, the injection mold is filled with plastic that out in the labels element ^¬ formed grooves are also filled with plastic. As a result, the desired flow aids form essentially within the label element. The shape, the course and the cross section of the flow aids are defined by the shape, the course and the cross section of the grooves introduced into the label element. The grooves are These are depressions which, similar to the tubular depressions in the spray mold, extend along the areas of the label element in which the flow front of the liquid plastic is to be influenced in a targeted manner.

Characterized in that the flow aids are formed according to the invention in the Etiket ^¬ th element, it is no longer necessary to introduce into the container used to prepare the injection form ^¬ flow aids. This simplifies the process, eliminating the need for special, expensive injection molds adapted to the product parameters, so that significant cost savings can be made.

In addition, a better quality of the container is achieved. Because the flow aids, which are formed according to the prior art in the injection mold, lead to ribs in the wall of the container. If the ribs are on the inside of the container, this results in the container being difficult to demold at the end of the production process. Also, after filling the container, the contents of the container can not be completely or only badly removed. For example, when removing the contents with a spoon, the ribs form an obstacle. If the ribs are formed on the outside of the container, this would lead to a Poor ^¬ th readability of a label on the wall of the container located label element. Since the flow aids are formed in the label assembly according to the invention, the thickened portions form in Wesentli ^¬ surfaces within the depressions of the labels in element. In the IML method, therefore, the recesses in the label element are filled with plastic. The thickenings or ribs formed by the flow aids thus extend between the outer surface of the container wall and the inside of the label element. Therefore, the surface the wall of the container neither inside nor outside affected by the flow aids. The inner surface of the wall of the container is smooth, so that the container is easy to demold and any content can be easily and completely removed from the container. The outer surface of the container wall is covered with the label element, the outwardly facing surface is not affected by the flow aids. The outer surface of Etiket ^¬ ten-element remains during and after the production of the container in its original state so that a label of the label member is retained and is legible.

Preferred embodiments of the invention are disclosed in the subclaims.

According to an advantageous embodiment of the invention, the label element is chosen so that it is congruent with the outer surface of the ^¬ wall of the container. Thus, the entire wall of the container can be formed by means of the flow aids in a desired and optimal shape and thickness.

It is advantageous if the label element has a plurality of partial label elements. This is particularly advantageous when Be ^¬ ratios, the one wall having a large area or a wall with differently shaped portions aufwei ^¬ sen. According to an advantageous embodiment of the invention, the wall of the container comprises a jacket, wherein a first label element applied to the outwardly facing shell ^¬ surface of the container and is selected such that it is congruent with the lateral surface. The label element is conveniently formed as a strip whose shape is determined so that the width of the strip at each point of the circumference corresponds to the height of the shell. The length of the strip corresponds at each height coordinate the jewei ^¬ ligen circumference of the outer surface of the shell of the container. When the strip is inserted into the injection mold, the two ends of the strip meet each other in a form-fitting manner. They cover the entire outer surface of the shell without overlapping. The grooves are provided in the first label member so as to extend from the lower edge to the upper edge of the shell. Thus, flow aids are provided by means of which the flow of the plastic melt over the entire surface and height of the shell can be controlled in a targeted manner.

According to a further advantageous embodiment of the invention, the wall of the container comprises a bottom, and a second label element is applied to the outwardly facing de base surface of the container. In this case, the second label element is chosen so that it is congruent with the bottom surface ^¬ and introduced grooves that emanate from a congruent to a gate for the Kunststoffschmel ^¬ ze point and extend to the outer edge of the soil. In this container, the flow of the plastic melt with the grooves acting as flow aids in the second label element can be targeted over the bottom surface of the container. In this way, the soil can be made optimally, thin and evenly, without flow aids must be introduced into the bottom part of the injection mold. Under congruent here and below is a covering of the wall, taking into account the usual, known to those skilled tolerances. When using a strip as a label element, the length of the strip is to be chosen so that it corresponds to the extent of the container ^¬ ses its scope. The tolerances are example ^¬ as to be selected that can form any additional unwanted flow aid between the ends of the strip and that the ends of the strip do not overlap in the injection mold. The width of the strip should be chosen so that it corresponds to the desired height of the container at the respective points. In the tolerances to be taken into ^¬ into account that the injection mold has to be up to the upper edge is filled with the molten plastic material, so that the container with the predetermined amount and with a suitable margin is formed. On the other hand, the strip must not protrude beyond the end of the injection mold as this would hinder the formation of the cup rim. Conveniently, the label element is formed from paper, cardboard, cardboard or other fibrous material. In label elements made of these materials, the grooves acting as flow aids can be reliably introduced in a simple and cost-effective manner. This can be done, for example, by embossing, milling, cutting or similar processes and, if appropriate, carried out simultaneously with the cutting or stamping process for producing the label element. When using these materials as a label element, the container can be made particularly inexpensive, since these materials are inexpensive and the amount of plastic needed for the container can be minimized. Further details, features and advantages of the present invention will become apparent from the following description of preferred embodiments with reference to the drawings.

Show it:

Fig. 1 is a schematic representation of a Ausführungsbei ^¬ game of a container according to the invention

Fig. 2 is a schematic representation of an Ausführungsbei ^¬ game of a label element according to the invention;

FIG. 3 shows another illustration of the embodiment of the label element according to the invention from FIG. 1; FIG.

4 is a schematic representation of a second embodiment of the label element according to the invention;

Fig. 5 is a schematic representation of the Ausführungsbei ^¬ game of the container of the invention of FIG. 1 after removal of the label element and

Fig. 6 is a further schematic representation of the execution example of the container according to the invention of Figure 1 after removal of the label element.

Figure 1 shows a container 1, which is prepared by a fiction, contemporary IML method. The container 1 has a wall which comprises a jacket 2 and a bottom 3. On the outer surface of the shell 2, a first label element 4 is applied by means of the IML method. On the outer surface of the bottom 3, a second label element 5 is applied, which is not visible here and is shown in Figure 4. The first and the second label element 4, 5 are connected to the container 1 due to the IML method. The first label element 4 covers the entire outer surface 6 of the shell 2 and extends from the lower edge 9 of the shell 2 to the upper edge 10 of the shell 2. Both the outer surface 6 of the shell 2 and the inner surface 7 of the shell 2 of the container 1 are smooth and have no structures due to the manufacturing process. The same applies to the inner surface 8 of the bottom 2 and not shown in the figure outer surface of the bottom 2 of the container 1. The first label element 4 has on the outer surface 6 usually a label, which is not shown here.

2 shows an embodiment of the first label element 4 is shown, which is applied in Figure 1 on the outer surface 6 of the shell 2 of the container 1. The shape of the first label element 4 is chosen so that the first label element 4 is congruent with the outer surface of the shell 2 of the container 1. On the upwardly facing in Figure 2 side of the first label element 4 grooves 11 are introduced. History and cross section of

Grooves 11 are chosen so that the grooves 11 are suitable in the IML method as flow aids for directing the plastic melt. In the example shown here Ausführungsbei ^¬ game of the invention the grooves 11 are curved and extend from the lower edge 12 to the upper edge 13 of the label member. 4

FIG. 3 shows the first label element 4 from FIG. 2 in a different representation, as in the injection mold for the Manufacture of the container 1 is introduced by the IML method. The two lateral edges 14 of the first

Label element 4 are joined together in a form-fitting manner, so that the first label element 4 completely covers the outer surface of the shell 2 of the container 1 to be produced, both with respect to the height and with regard to the circumference of the shell 2.

FIG. 4 shows the second label element 5, which is applied to the bottom 3 of the container 1 in the IML process and connected thereto. The second label ^¬ th element 5 is congruent in shape with the

Surface of the bottom 3 of the container 2. It has introduced grooves 11, which emanate from a congruent to a starting point for the plastic melt point 15 and extend to the outer edge 16 of the second label element 5 and the bottom 3 of the container 1 , The grooves 11 in the second label element 5 extend in a star shape from the point 15 to the edge 16 of the second label element 5. The grooves 11 are formed with respect to their course and cross section so that they during the IML process as flow aids for steering the plastic melt act.

The first label element 4 and the second label element 5 are formed from paper, paperboard, cardboard or other fibrous material suitable for use with a label in an IML process. Label elements made of these materials have the advantage that they are inexpensive and can be saved in the production of plastic cups plastic material. In addition, the grooves acting as flow aids can be easily incorporated into these materials. In principle, the invention can also be carried out with label elements of other materials which can be used in an IML process, and the materials are not intended to be limiting of the invention. In Figures 5 and 6, the container 1 of Figure 1 is ge ^¬ shows, in which the first label element 4 and the second label member 5 have been removed from the casing 2 and from the bottom. 3 On the outer surface 6 of the shell 2 and on the outer surface 17 of the bottom 3 of the container 1 ribs 18 can be seen, in their course and in shape substantially in the grooves 11 shown above in the first and in the second label element and that served as flow aids during the IML process. The

Ribs 18 extend in the labeled container 1 between the label elements and the respective outer surface of the container 1. The ribs 18 formed by the flow aids are in the labeled state of the container neither on the label surface nor on the inside of the container 1 can be seen. Both surfaces are smooth. Only by removing the respective tag element, the flow ^¬ aids or ribs 18 on the container are visible again.

In the following, a preferred embodiment of the method according to the invention will be described with reference to the figures. In an IML process, the second tag element is inserted so into the bottom region of the injection mold 5, the embossed in the first label element grooves facing inward and the bottom of the to-forming container 1 abge ^¬ covers. The first label element 4 is inserted in the representation shown in Figure 3 in the jacket region of the injection mold. In this case, the grooves 11 inward and the lateral edges 14 are positively against each other. The point 15 on the second label element 5 from which the grooves 11 run radially outward to the edge 16, is located above the gate of the injection mold.

The plastic melt is injected at a gate in the injection mold and along the surface of the

Injection mold guided, which form the bottom 3 and the shell 2 of the container 1. The grooves 11 in the first and in the second label element 4, 5 are filled with the liquid plastic of the plastic melt. Due to the resulting thickening of the plastic remains longer flowable and the plastic melt can be directed by means of flow aids targeted over the bottom and the lateral surface. The shape and the cross section of the flow aids are selected depending on the process parameters and the requirements for size and shape of the container. After the injection mold is filled with the plastic melt and the plastic has cooled, the container is removed by demolding from the injection mold. The labeled container can now be filled in other processes or otherwise used.

The result is a container 1 in this method, which is provided with a first label element 4 on the jacket 2 and a second label element 5 on the bottom 3. The formed by the grooves 11 acting as flow aids

Ribs 18 extend between the label elements 4, 5 and the outer surface of the shell 2 and the bottom 3. Therefore ent ^¬ stands a container with inner and outer walls, which is not affected by the structure of the flow aids.

It should be understood that the description is of preferred embodiments of the invention, which is not intended to limit the invention. Thus, For example, for the production of the container shown only one of the label elements are used. When playing, only the first label element is used in ^¬, the base of the cup without flow aids and thus made thicker can be, or it can be used for the bottom flow aids which are introduced into the injection mold, so that only the wall of the container is variable. Also, applications are conceivable in which only portions of the wall of the container are made with a label element, label elements are divided, as it appears suitable for the shape and use of the container. Also, the container may have any shape. For example, the Be ^¬ ratio can be formed with a square bottom and square jacket, with different wall height or without a flat bottom surface. Depending on the desired shape of the container suitable flow aids can be determined. Depending on the requirements, it can also be determined whether all flow aids are introduced into one or more label elements or whether only a part of the flow aids is provided in the label elements and another part is provided in the injection mold. This can be chosen according to product requirements, existing injection molds and other process conditions.

LIST OF REFERENCE NUMBERS

I container

2 coat

3 floor

4 first label element

5 second label element

6 outer surface of the jacket

7 inner surface of the jacket

8 inner surface of the soil

9 lower edge of the jacket

10 upper edge of the jacket

II grooves

12 lower edge of the label element

13 upper edge of the label element

14 lateral edges of the label element

15 point on the 2nd label element

16 edge of the 2nd label element

17 outer surface of the soil

18 ribs

Claims

claims

1. A method for producing a container made of plastic ^¬ material according to an in-mold labeling (IML) method in which a label element is inserted into an injection mold such that the label element at least a portion of a wall to be generated of the container covered

Plastic melt is injected at a gate, and along the wall of the container forming surface of the injection mold is guided so that the container is formed, wherein the label element is back-injected and connected to the wall of the container, characterized in that the label Element (4, 5) on the side facing the wall of the container (1) side grooves (11) has up the course and cross section are chosen so that the grooves (11) during the IML process with plastic ^¬ material fill, so that form in the grooves (11) flow aids through which the plastic melt in the region of the label element (4, 5) is directed targeted.

2. The method according to claim 1, characterized in that the label element (4,5) is selected so that it is congruent with the wall of the container to be produced (1).

3. The method according to claim 1 or 2, characterized in that the label element (4,5) comprises a plurality of partial label elements.

4. Container made of plastic with a wall and a Eti ^¬ chain element, which is Herge ^¬ presents an IML method that at least a portion of the wall of the

Container covered with the label element and connected is, characterized in that the label element (4, 5) on the side facing the wall of the container (1) side grooves (11) which are filled with plastic, wherein course and cross section of the grooves (11) chosen so are that the grooves (11) during the IML process fill with art ^¬ material so that the grooves form (11) flow aids, through which the plastic melt in the region of the label member (4, 5) is selectively steered , 5. Container according to claim 4, characterized in that the label element (4,

5) is selected so that it is congruent with the outer surface of the wall of the container (1).

6. Container according to claim 4 or 5, characterized marked, that the label element (4, 5) comprises a plurality of partial label elements.

7. Container according to one of claims 4 to 6, characterized in that the wall of the container (1) comprises a jacket (2), wherein a first label element (4) applied to the outwardly facing lateral surface of the container (1) and is selected so that it is congruent with the shell ^¬ surface, and in the first label member (4) introduced groove (11) from the lower edge (12) to the upper edge (13) of the skirt (2 ).

8. Container according to one of claims 4-7, characterized in that the wall of the container comprises a bottom (3), wherein a second label element (5) is applied to the outwardly facing bottom surface of the container (1) and so is chosen so that it is congruent with the bottom surface ^¬ same, and introduced grooves (11) which konkon from one to a starting point for the plastic melt. go out green point (15) and extend to the outer edge of the soil.

9. Container according to one of the preceding claims 4-8, characterized in that the label element (4, 5) made of paper, cardboard, cardboard or other fibrous material is formed.

10. Container according to one of claims 4-9, characterized in that the grooves (11) by embossing, milling or cutting in the label element (4, 5) are formed.

11. Label element for use in an IML process for producing a container according to claims 1 to 10, characterized in that the label element (4, 5) on one side grooves (11), whose course and

Cross-section are chosen so that the grooves (11) can fill currency ^¬ rend of the IML technique with plastic, so that in the grooves (11) form flow aids, through which the plastic melt in the region of the label member (4, 5 ) is specifically steerable.

12. Label element according to claim 11, characterized in that the label element (4, 5) made of paper, cardboard, cardboard or other fibrous material is formed.

13. Label element according to one of claims 11 or 12, characterized in that the grooves (11) are formed by stamping, milling or cutting in the label element (4, 5).