DE202011004393U1 - Sealing arrangement for blister packs - Google Patents

Abstract

Sealing arrangement comprising a sealing tool (1) for sealing blister packs (3) containing loose powder (2), the blister pack (3) comprising a blister tray (4), a peel seal film (5) and a stripping direction (6) of the peel seal film (5 ), and wherein the sealing tool (1) comprises a tool base (7) receiving the blister shell (4) and a tool shell (8) facing the sealing process of the peel seal film (5), with a sealing surface (9), characterized in that the sealing surface ( 9) has a structuring with linear, in particular rectilinear depressions (10) and between the linear depressions (10) and with respect to these elevated pressure surfaces (11), wherein the line-shaped depressions (10) relative to the stripping direction (6) in one of 90 ° deviating angle (α) are.

Description

The invention relates to a sealing arrangement for blister packs with the features according to the preamble of claim 1 and a sealed blister pack.

Blister packs are used in numerous applications. In the pharmaceutical sector, drug preparations are stored ready for use in various dosage forms in suitable blister packs until use. The blister pack comprises a blister tray, in the cavity of which the active substance preparation is accommodated, and a sealing film, which is tightly sealed on a peripheral sealing portion of the blister tray. The sealing is usually carried out by means of a heat-sealing medium under the action of pressure and temperature. For this purpose, a sealing tool is provided with an upper tool part and a lower tool part, which are pressed against each other with the interposition of the blister shell and the sealing film. With such sealed blister packs, two types are distinguished:
The first and most common type contains isolated, mechanically related preparations such as tablets, capsules or the like. The mechanical integrity of such a dosage form allows the tablet, capsule or the like to be pushed through the sealing foil by means of finger pressure and deformation of the blister shell. In such a "blubber blister" certain requirements are placed in particular on the sealing film and its sealing with the blister tray. The sealing foil must have sufficient strength to perform its protective function. On the other hand, it must be able to be severed at a defined breaking strength to allow the drug to be squeezed out. There are known designs in which the sealed seam is structured with dots or lines, wherein at the points or lines during the sealing process an increased surface pressure and also an increased heat input is provided.

This should be distinguished from blister packs containing a loose powder. Such blister packs are intended, for example, for use in inhalers for the pulmonary administration of powdered medicaments. The loose powder form does not allow it to be pushed through the sealing film because the powder is too flexible and would experience undesirable compression when pressure is applied. Rather, in this case the sealing film is designed as Abziehsiegelfolie, which is peeled off with the application of train from the blister tray. This peeling process is carried out automatically mechanically in the aforementioned example of the inhaler, so that this results in special requirements for the peel-off film and its sealing with the blister shell.

With such "peel-off blisters", the peel-off sealing film must not tear during the opening process. The requirement profile of the sealed seam, in addition to impermeability and the greatest possible adhesive force, also comprises a defined solubility, in particular automatically to be carried out, with a large peel force that is uniform in its course. In addition, the heat input required for this purpose must be taken into account in the manufacture of the sealed seam, since in blister shells filled to the brim with powder in particular-unlike push-through blisters-unwanted heat input into the powder can hardly be avoided. In particular, there is a risk that partial quantities of the powder adhere to the peel-off sealing film or its heat-sealing medium layer.

For the above-mentioned reasons, the sealing seam is fundamentally different in the case of a peeling blister filled with powder and also the associated sealing tool than in the case of a blister blister. According to the state of the art, smooth, flat sealing seams are used in order to ensure not only a high adhesive force but also a uniform, non-destructive peelability of the peel-off sealing film, while maintaining the impermeability requirement. The structuring of the sealing seam known from push-through blisters could not be adopted, since in this way an uneven, jerking force curve with too low a force level was produced during the peel-off process of the peel-off sealing film. However, the known for Abziehblister smooth seal seam is unsatisfactory in other respects. Large adhesive forces on the one hand and a uniform, defined force curve during removal on the other hand were not achievable in this combination to the desired extent. In particular, the problem of powder adhesion to the peel-seal film and the heat input could not be satisfactorily solved.

The invention has the object of developing a generic sealing arrangement such that a dense sealing seam with high and uniform peel force of Abziehsiegelfolie and a reduced powder adhesion to the peel seal film is achieved.

This object is achieved by a sealing arrangement having the features of claim 1.

The invention is further based on the object of specifying a blister pack for loose powder, the Abziehsiegelfolie sealed at a reduced tendency to powder adhesion sealed to the blister shell and thereby removable with high and uniform peel force.

This object is achieved by a blister pack with the features of claim 8.

According to the invention, it is provided that the sealing surface of the Abziehsiegelfolie facing tool upper part has a structuring with linear, in particular rectilinear depressions and lying between the linear recesses and with respect to these raised pressure surfaces, wherein the line-shaped recesses relative to the stripping direction are at a different angle of 90 ° , Advantageously, the aforementioned angle is in a range of from 30 ° to 60 ° inclusive and in particular is at least approximately 45 °.

The pressure surfaces raised in relation to the linear depressions produce locally increased surface pressures during the sealing process and a locally increased, but overall heat input, whereby not only the tightness but also a high pull-off force is achieved during later opening of the blister packaging. The angular arrangement of the line-shaped recesses leads during the removal process to the fact that the withdrawal force does not act alternately on areas with higher and lower sealing force. Rather, the withdrawal force always acts simultaneously on areas with increased adhesive force corresponding to the pressure surfaces, and areas with lower adhesive force corresponding to the linear depressions, so that along the entire Ablöseweges a nearly uniform total force is applied. As a result, high tightness, high pull-off force and uniform course of the pull-off force along the extraction path are combined. In particular, a markedly reduced tendency of the charged powder to adhere to the peel-off sealing film or its heat-sealing medium could be observed.

It may be expedient to provide a family of at least approximately parallel line-shaped recesses. In an advantageous embodiment, intersecting line-shaped depressions are provided which delimit a multiplicity of printing surfaces which are separate from one another. In particular, the intersecting line depressions are arranged in a uniform pitch to form square pressure surfaces. It has been found that, as a result, the desired effect can be achieved in a pronounced manner.

The same applies to the following dimensions: The ratio of the grid dimension to a width of the line-shaped depressions is preferably in a range from 2.0 inclusive to 4.0 and is in particular at least approximately 3.0. The line-shaped depressions have a width that advantageously lies in a range of 0.2 mm to 0.3 mm inclusive, and in particular is at least approximately 0.25 mm. The pressure surfaces advantageously have a width that lies in a range of 0.25 mm to 0.75 mm, and in particular is at least approximately 0.955 mm.

The blister tray has a cavity with a peripheral peripheral wall, a flat sealing portion, and a transition section which is rounded in cross-section and conveys the peripheral wall into the sealing portion. In a preferred embodiment of the invention, the sealing surface of the upper tool part is interrupted by means of a tool lower part towards open, during the sealing process over the cavity positioned recess, wherein the recess is bounded by a circumferential edge and the sealing surface up to the peripheral edge during the sealing process in particular completely over the flat sealing portion of the blister tray is positioned outside the rounded transition section. This ensures that sealing pressure and heat input are made only at the flat sealing portion, while the cavity, including the rounded transition section thereof is kept free. Even with blisters filled to the brim with powder, the risk of powder adhesion to the peel-seal film and excessive heat input into the powder is thereby minimized.

An embodiment of the invention is described below with reference to the drawing. Show it:

1 in a schematic cross-sectional representation of a sealed blister pack according to the invention when peeling off their peel-seal film;

2 in a schematic cross-sectional view of an inventively executed sealing tool during the sealing process of the blister pack according to 1 ;

3 in a perspective view of the tool top of the sealing tool after 2 with a plurality of the sealing surface breaking through recesses;

4 in a plan view an enlarged detail of the sealing surface of the tool upper part 3 with details of the structured design of the sealing surface;

5 a section of a cross-sectional view of the arrangement according to 4 with details of the geometric configuration of linear depressions in the sealing surface.

1 shows a schematic cross-sectional view of a sealed blister pack according to the invention 3 , The blister pack 3 includes a blister tray 4 with a peel seal film sealed tightly thereto 5 , The blister tray made in one piece from a deep-drawn aluminum composite material 4 has a cavity 12 on that with a loose powder 2 especially filled to the brim. In place of the aluminum composite may also be another material for the production of the blister tray 4 be appropriate. The powder 2 is in the illustrated embodiment, a pharmaceutical drug preparation for pulmonary administration by means of an inhaler, not shown. The blister pack 3 but also other powders 2 contain. In addition, a partial filling of the blister pack 3 with the powder 2 be provided.

The blister tray 4 has a flat seal section 14 out of whose plane out the aluminum composite material of the blister tray 4 for the formation of the cavity 12 is deep-drawn. Here are a circumferential peripheral wall 13 , a transitional section 15 , as well as a floor 18 formed the cavity 12 limit downwards and sideways. The peripheral wall 13 is by means of the rounded in cross-section and also around the cavity 12 circumferential transition section 15 tangential in the seal section 14 transferred. The tight and around the cavity 12 all-round peel-seal film 5 limits the cavity 12 upwards, leaving the cavity 12 including the powder contained therein 2 sealed on all sides by the peel-seal film 5 , the transition section 15 , the peripheral wall 13 and the floor 18 is closed.

The removal of the powder 2 from the blister pack 3 unlike a hard body filling (tablet, capsule) is not by manual pressure on the ground 18 and subsequently by squeezing the peel-seal film 5 but by peeling off the peel-seal film 5 at one of its ends 19 in a stripping direction 6 , The removal direction 6 lies here parallel to the transverse axis of the blister pack 3 but may also be parallel to its longitudinal axis or in another direction. In the embodiment shown, the removal of the peel-seal film takes place 5 automatically mechanically by the above-mentioned, not shown inhalation device. But it can also be provided a manual peeling.

2 shows in a schematic cross-sectional representation of a sealing arrangement according to the invention, the blister pack 3 to 1 and a geometrically adapted sealing tool 1 includes. The sealing tool 1 consists of a tool lower part 7 and a tool shell 8th , between which the at least approximately complete, here brimming with the powder 2 filled blister tray 4 as well as the peel-seal film 5 are inserted for the sealing process. The peel-seal film 5 is on her blister shell 4 facing side over the entire surface coated with a heat sealant, not shown. Instead of the heat sealing lacquer, however, it is also possible to use another heat-sealing medium. The lower part of the tool 7 is with a recess 20 for receiving the cavity 12 provided, the blister shell 4 with its circulating seal section 14 outside the recess 20 on the tool shell 8th facing end face of the lower tool part 7 rests.

Above it is the tool top 8th arranged and has a sealing surface 9 on, during the sealing process the tool lower part 7 and the peel-seal film 5 is facing. The sealing surface 9 of the tool shell 8th is by means of a tool lower part 7 open towards the sealing process above the cavity 12 positioned recess 16 interrupted, with the recess 16 from a circumferential, to the sealing surface 9 adjacent edge 17 is limited. Shape and size of the recess 16 are so in shape and size of the cavity 12 adjusted that the circumferential edge 17 and the seal surface formed outside thereof 9 during the sealing process above the flat sealing section 14 the blister tray 4 outside the transitional section 15 are positioned while the recess 16 completely the peripheral wall 13 including the transition section 15 up to their tangential transition to the seal section 14 covered. From this as well as by entry of temperature and pressure between lower tool part 7 and tool shell 8th By activating the heat-sealing medium, sealing of the peel-off sealing film takes place 5 solely on the seal section 14 the blister tray 4 without the heat-sealing medium between the peel-seal film 5 and the blister tray 4 in the area of the transition section 15 is activated. This will prevent a subset of the powder 2 especially in the area of the transitional section 15 on the peel-seal film 5 adheres. In addition, there is no appreciable heat input into the powder 2 instead of which the quality of the powder 2 could affect. To achieve this, it is provided according to the invention that the peripheral edge 17 radially inward to maximum at the tangential transition of the transition section 15 to the seal section 14 or outside of it, but not internally in the area of the transitional period 15 survives. This applies at least for the greater part of the circumferential edge 17 and preferably for the peripheral edge 17 all in all.

The 1 and 2 only partially show the conditions in the range of a single blister 3 and the associated portion of the sealing tool 1 , In the practical embodiment, multiple, in strips or other form related blister packs 3 sealed at the same time. An embodiment of a correspondingly designed upper tool part 8th is in perspective view in 3 shown. Accordingly, the tool shell 8th as a block-shaped block with a flat sealing surface 9 designed, with numerous recesses 16 each with circumferential edges 17 starting from the continuous sealing surface 9 inside the tool shell 8th are incorporated. Exemplary here are the recesses 16 arranged in the form of a rectangular matrix. But there may be other geometric patterns of the recesses 16 in adaptation to the particular desired geometric distribution of individual blister packs 3 ( 1 . 2 ) with a correspondingly adapted lower tool part 7 ( 2 ) be appropriate.

4 shows an enlarged sectional view of a plan view of the upper tool part 8th to 3 on its sealing surface 9 in the area of a single recess 16 , It can be seen that the recess 16 adapted to the shape of the blister pack 3 ( 1 . 2 ) has an oblong oval shape, the peeling direction 6 parallel to the transverse axis of the blister pack 3 or the recess 16 lies. There may also be other forms of blister packaging 3 and the recess 16 and another relative position of the peeling direction 6 to be useful.

According to the invention it is provided that the outside of the recess 16 or its edge 17 trained seal surface 9 is executed structured, the structuring of the sake of clarity is shown only in sections. The structuring is by linear, here rectilinear depressions 10 and between the linear depressions 10 lying and against these raised pressure surfaces 11 educated. The printing surfaces 11 lie as shown 5 at the height level of the sealing surface 9 , from which the line-shaped depressions emerge 10 extend in the depth direction. One half of the line-shaped depressions 10 runs with parallel longitudinal axes 21 , it may be sufficient that only and exclusively such parallel longitudinal axes 21 are provided. In the advantageous embodiment shown here, a further half of the line-shaped depressions extends 10 along parallel longitudinal axes 22 , wherein the line-shaped depressions 10 with the longitudinal axes 21 and the linear depressions 10 with the longitudinal axes 22 intersect in such a way that between them a plurality of separate pressure surfaces 11 is trained. In the embodiment shown are the longitudinal axes 21 . 22 at a right angle to each other. But it can also be another angle advantageous. In addition, the longitudinal axes are 21 . 22 at an angle α to the peeling direction 6 , wherein the angle α deviates from 90 °. Suitably, the angle α is in a range of from 30 ° to 60 ° inclusive, and in the preferred embodiment shown is at least approximately 45 °.

In addition, the 4 be taken that the intersecting linear depressions 10 in a uniform grid r with the formation of square pressure surfaces 11 are arranged. The printing surfaces 11 but may also be rectangular or in any other form. The grid r is expediently in a range of from 0.5 mm to 1.0 mm inclusive and is expediently at least approximately 0.75 mm. In the exemplary embodiment shown, the grid dimension r = 0.745 mm and applies to all linear depressions 10 with both different longitudinal axes 21 . 22 ,

5 shows in an enlarged detail a cross section through the upper tool 8th after the 4 and 5 with further details on the design of the structured sealing surface 9 , Accordingly, the line-shaped depressions 10 a V-shaped cross section with an opening angle β, wherein the opening angle β in the illustrated embodiment is 60 °. At the height level of the individual lying in a common plane printing surfaces 11 have the linear depressions 10 a width b which is advantageously in a range of from 0.2 mm to 0.3 mm inclusive, and in the preferred embodiment shown is at least approximately 0.25 mm. From this and from the opening angle β of 60 ° follows a depth t of the line-shaped recesses with respect to the plane of the pressure surfaces 11 of about 0.22 mm. From the synopsis of 4 and 5 with the above dimensions also follows that the here square pressure surfaces 11 have a width B which is advantageously in a range of from 0.25 mm to 0.75 mm including, and in the preferred embodiment shown is at least approximately 0.955 mm. In addition, advantageous ratios, ie the ratio of the grid r to the width b of the linear depressions result 10 is in the range of 2.0 to 4.0 inclusive. In the preferred embodiment shown, the aforementioned ratio is at least approximately 3.0.

Referring again to 2 is due to the design of the sealing surface 9 after the 4 and 5 achieved that when sealing the peel-seal film 5 on the seal section 14 by means of the raised pressure surfaces 11 a locally increased entry of pressure and temperature into the peel-seal film 5 and the associated heat-sealing medium is made, whereby at these points an increased, but in the result almost uniformly distributed adhesive force is generated. This leads desirably to that according to the illustration 1 the desired high peel force at the end 19 the peel-seal film 5 in the stripping direction 6 entry. Due to the geometric arrangement of the linear depressions 10 after the 4 and 5 in particular at an angle α to the withdrawal direction 6 However, this high peel force is at least approximately constant over the entire removal path, without local force peaks or force drops and a concomitant bucking form. In the aforementioned mechanical inhalation device can thus be an automatic and mechanical peeling off the peel-seal film 5 be performed with the desired uniform and high peel force. In the closed state of the above-sealed blister pack 3 this is due to the high adhesive force between the peel-seal film 5 and the blister tray 4 reliably tight. In addition, there is a significantly reduced tendency of the powder 2 to adhere to the peel-seal film 5 ,

Claims (9)

Sealing arrangement comprising a sealing tool ( 1 ) for sealing a loose powder ( 2 ) containing blister packs ( 3 ), the blister pack ( 3 ) a blister tray ( 4 ), a peel-seal film ( 5 ) as well as a removal direction ( 6 ) of the peel-seal film ( 5 ), and wherein the sealing tool ( 1 ) the blister tray ( 4 ) receiving tool lower part ( 7 ) as well as a sealing process of the peel-off film ( 5 ) facing tool upper part ( 8th ) with a sealing surface ( 9 ), characterized in that the sealing surface ( 9 ) a structuring with linear, in particular rectilinear depressions ( 10 ) and between the linear depressions ( 10 ) and against these raised pressure surfaces ( 11 ), wherein the linear depressions ( 10 ) opposite the withdrawal direction ( 6 ) lie in an angle deviating from 90 ° (α). Sealing arrangement according to claim 1, characterized in that the angle (α) is in a range of from 30 ° inclusive to 60 ° inclusive and in particular at least approximately 45 °. Sealing arrangement according to claim 1 or 2, characterized in that intersecting linear depressions ( 10 ) are provided which a plurality of separate pressure surfaces ( 11 ) limit. Sealing arrangement according to claim 3, characterized in that the intersecting linear depressions ( 10 ) at a uniform pitch (r) to form square pressure surfaces ( 11 ) are arranged. Sealing arrangement according to one of claims 1 to 4, characterized in that the linear depressions ( 10 ) have a width (b) and a pitch (r), wherein the ratio of the grid dimension (r) to the width (b) of the line-shaped depression (r) ( 10 ) is in a range of 2.0 to 4.0 inclusive, and more preferably at least approximately 3.0. Sealing arrangement according to one of claims 1 to 5, characterized in that the line-shaped depressions ( 10 ) have a width (b) which is in a range of from 0.2 mm to 0.3 mm inclusive and in particular at least approximately 0.25 mm, and in that the pressure surfaces ( 11 ) have a width (B) which is in a range of from 0.25 mm to 0.75 mm inclusive, and more particularly at least approximately 0.955 mm. Sealing arrangement according to one of claims 1 to 6, characterized in that the blister tray ( 4 ) a cavity ( 12 ) with a peripheral peripheral wall ( 13 ), a flat seal section ( 14 ) as well as the peripheral wall ( 13 ) in the sealing section ( 14 ) passing, in cross-section rounded transition section ( 15 ), and that the sealing surface ( 9 ) of the tool upper part ( 8th ) by means of a tool lower part ( 7 ) open during the sealing process above the cavity ( 12 ) positioned recess ( 16 ) is interrupted, wherein the recess ( 16 ) from a circumferential edge ( 17 ) and the sealing surface ( 9 ) up to the peripheral edge ( 17 ) in the sealing process, in particular completely over the flat seal portion ( 14 ) of the blister tray ( 4 ) outside the rounded transition section ( 15 ) is positioned. Blister pack ( 3 ) containing a loose powder ( 2 ), with a blister tray ( 4 ), a peel-seal film ( 5 ) and with a removal direction ( 6 ) of the peel-seal film ( 5 ) sealed with a sealing arrangement according to one of claims 1 to 7. Blister pack according to claim 8, characterized in that the cavity ( 12 ) of the blister pack ( 3 ) at least approximately completely with the dissolve powder ( 2 ) is filled.

Images