IE890372L

IE890372L - Process for producing blister packs and apparatus for sealing blister packs

Info

Publication number: IE890372L
Application number: IE890372A
Authority: IE
Inventors: Dieter Stephan; Gunter Stephan; Klauspeter Amenitsch
Original assignee: Hillstar Ltd
Priority date: 1988-02-25
Filing date: 1989-02-06
Publication date: 1989-08-05
Also published as: PT89800A; IE62238B1; PT89800B; EP0330166B1; DE58905986D1; EP0330166A1

Description

X 6223s "Process and Apparatus for Producing Blister Packs" The invention relates to a process for producing blister packs of defined volume having a number of shaped nests/-cavities for receiving products to be packed in the blister 5 packs, and having a plane surface of a predetermined surface area, comprising the steps a) to g) of patent claim 1, as well as an apparatus for producing blister packs of the above-mentioned species, the apparatus comprising devices according to features a) to g) of the preamble of patent 1 0 claim 2.

Such process and apparatus are known from DE-A-3 111 537 with regard to substantial steps for the production of individual, closed portioned packs.

The method of producing blister packs has increasingly come 15 into practice for medicaments in tablet or capsule form; it is now scarcely possible to find tablets packed in small tubes. However, blister packing is also used for articles from other, rather widely varying fields, such as e.g. in the domestic, foods, confectionery, business, office and do-it-20 yourself fields and the like. Nowadays it is possible to find everywhere tubes, bottles, tools, workpieces such as nails, drawing pins, clips, spice containers etc. in blister 2 form. All these details are of a purely exemplified nature, because developments are such that the fields of use are more likely to be extended than restricted.

In view of the increasing scarcity of raw materials and en-5 ergy sources and the attempts particularly made to reuse packing materials, it is known (DE-OS 31 10 254), to recycle the large amounts of waste occurring in particular in the pharmaceutical industry as faulty charges during the production of blister packs. As a result of the separation pro-1o blems associated with conventional aluminium - PVC material combinations and for avoiding such problems, this material combination, i.e. PVC and aluminium together, is supplied to a crushing machine and granulated and the aluminium - PVC granules obtained are processed with plastics additives, 15 especially raw plastic granulates to form new plastics products, particularly in press working, injection moulding or extrusion processes. The resulting material, which makes it unnecessary to dispose of the waste, is intended for use in plastics mould constructions for PU-foaming moulds, as a fil-20 ling material in adhesives and as sealing compounds in the building industry, and as an admixture in the production of chipboard. Thus, all these relate to the use of a mixed material for mass produced articles, where significance is not attached to the quality of the starting product, but they 25 rather relate to lower quality filling and additive material which can be used without having a detrimental effect on the end product. Thus, no particular account is taken of the high value and price of the basic materials aluminium and plastics, such as PVC. In fact, problems apparently occur in 3 0 that in the case of film webs consisting of different material, which webs in the case of blister packing medicaments generally have PVC as the material for the shaping film and aluminium as the cover film, - although in many other areas 3 for example other plastics may be used as shaping films and paper materials as the cover film as well, - and are interconnected in whole-area form by sealing or other adhesion, these materials thus occur together, i.e. in composite form. 5 As a result, hitherto the interconnected waste strips or punchings occurring in quantities of 10 to 20% of the packing film webs at the end of blister pack production processes have not been supplied to the recycling process and instead, unlike with the known recycling of faulty charge waste in the 10 pharmaceutical industry, have still been looked upon as un usable waste and consequently had to be disposed of.

Thus, the problem of the present invention is to make the blister packing process such that a waste product appropriate for recycling is obtained, which enables the recovery of the 1 5 expensive raw materials individually and therefore with a considerable material cost saving, together with providing an apparatus suitable for this purpose which can be manufactured at low price and, if necessary, retrofitted in already existing systems. 2 0 This problem is solved according to the present invention in the case of the'initially specified procedure by the features of the characterizing portion of patent claim 1, and in the case of the initially described apparatus by the features of the characterizing portion of patent claim 2. 2 5 Thus, while solving the set problem, the process and appara tus according to the present invention provide a possibility, immediately during the blister packing, of obtaining a waste material with only limited technical expenditure which can be directly and individually supplied to the recycling process 3 0 for each of the single product components. Therefore, this packing process is much more friendly with regard to the en- 4 vironment, and energy saving when bearing in mind that the film web waste during the production of such blister packs can amount to between 10 and 20% and can be supplied for recycling without any subsequent separation process. With 5 the indicated increasing tendency to blister packing, this represents an important step aiding the saving of the ever scarcer raw materials, as, moreover, due to the fact that the subsequent costs for the reprocessing of the waste can be kept very low, it is possible to achieve an effective cost 1 o saving. The apparatus structure according to the invention makes it possible in a simple manner to only connect the surface of the actual pack to the shaping film, whereas all the remaining parts of the passing films remain separate from one another. The overall structure of such an apparatus may be 1 5 produced at low expense and can easily be retrofitted in ex isting installations, whilst it is also possible to rework existing tools, e.g. by milling or eroding. The punching tool in a separating or punching station of the installation is constructed with the size of the pack, so that it can se-20 parate the pack from the running film strand precisely along the active surfaces, so that the waste occurring laterally and between the individual packs is removed in a continuous waste strand and can be individually further processed. By the fact that during sealing the sealing film is subjected to 25 the action of the pressure and heat necessary for sealing purposes exclusively in the contact areas to the deep-drawn shaping film carrying the packed products, it is, moreover, possible to handle the packed products extremely carefully, which is in particular of significance with heat and/or 30 pressure-sensitive materials, such as e.g. soft gelatine capsules. In this context, the fact that the active surface of the upper tool part is formed with heating-free locations corresponding to the number, size and positioning of the recesses in the lower tool part, essentially helps to avoid 5 that the heat and pressure to be supplied during the sealing process have any negative influence on the packed products located in the deep-drawn blisters of the shaping film, which influence is particularly prejudicial if the packed products 5 are sensitive pharmaceuticals, such as e.g. soft gelatine capsules.

It is known (v. DE-A1-31 11 637), as initially stated, to perform a sealing of plastic and metal films in the course of sealing portioned packs exclusively in the immediate edge re-10 gion in order to enable a separate recycling of the film remainders resulting during punching in an economical manner. However, since in such processing only an annular sealing, i.e. a line sealing is aimed at and actually occurs, no suggestion can be derived therefrom how one ought to proceed in 15 the case of blister packs to be sealed over the whole surface when one is confronted with the specific problem on which the present invention is based.

Preferably the active surface of the second, upper tool part can be raised with respect to the remaining surface portions 2 0 thereof. During retrofitting, this can easily be provided on existing tool parts by milling or eroding the surface substantially corresponding to the film strand width in the hitherto known sealing plates, so that only the surface of the pack to be produced remains as the active surface. 25 Other advantages and embodiments or possibilities of realization of the invention can be gathered from the following description of exemplified embodiments represented in the diagrammatic drawings. It is shown in: 30 Fig. 1 the principle of a blister pack installation in side view; 6 Fig. 2 a sealing tool in side view and in the moved apart state; and Fig. 3 the bottom view of an upper tool part corresponding to III-III in Fig. 2. 5 A blister packing installation shown in Fig. 1, which is only represented in basic form and does not show any details, comprises on a machine bed 10 for producing blister packs for pharmaceuticals (tablets, capsules, etc.) by means of a shaping film 11 generally referred to and applied as the base 10 film and which runs off a storage reel 111, and of a cover film 12, which runs off a storage reel 121, a shaping station 13 in which the shaping film 11 is deep-drawn for forming blisters 112 (Fig. 2) for receiving tablets 3, a sealing station 14 in which the shaping film 11 and cover film 12 are 15 interconnected under heat and pressure supply, a separating or punching station 15, in which the finished blister packs are punched from the continuous film web, as well as a waste collection station 16, where there are separate collecting reels 161 for the waste of the shaping film 11, and 162 for 20 the waste of the cover film 12. This waste collecting station 16 in its separate construction for the two films, as opposed to the prior art in which the waste materials can only be jointly collected, made possible by the special construction of the sealing tool according to Fig. 2 and 3. It 25 is, of course, not unconditionally necessary to roll up the waste and instead the waste, obviously preferably separately, can each be supplied to a first reprocessing process, e.g. constituted by a chopping and/or granulating process.

A sealing tool 2 forming the essential component of the seal-30 ing station 14 comprises, as shown in Fig. 2, a lower tool 7 part 21 in the form of a counterholding plate and an upper tool part 22 in the form of a sealing punch. The two tool parts 21, 22 are shown in their inoperative position, i.e. spaced from one another. The double film web, consisting of 5 the shaping film 11 with the blisters 12 already preshaped thereon and packed products 3 placed therein, in the present case in the form of tablets, and of the cover film 12 passes in timed manner between the two tool parts. In the represented position, the blisters 112 are located above recesses 10 211 shaped from the counterholding plate 21. The sealing process can take place in this position, in that the counter-holding plate 21 is moved upwards in the direction of arrow A, so that the blisters 112 are received by the recesses 211, and that the counterholding plate 21, which is not heated and 15 is if necessary appropriately cooled, firstly engages against the underside of shaping film 11. The sealing punch 22, which is heated to the necessary temperature, is conventionally fixed, but in some apparatuses can also be moved downwards in the direction of arrow B. As a result of this rela-20 tive movement the surface of the shaping film 11 presses against cover film 12. The underside of the cover film 12 is provided with an adhesive layer necessary for joining and which as a result of the pressure produced between counter-holding plate 21 and sealing punch 22 and of the heat trans-25 ferred by punch 22 brings about the connection with the surface of shaping film 11.

From the bottom view of Fig. 3 in conjunction with the side view of Fig. 2, it is apparent that the sealing punch 22 has a raised active face 221, whose surface at the maximum pre-30 cisely corresponds to the surface of the pack to be produced or is smaller that the latter, so that it is possible to avoid at any rate that the punching waste/punching screens have any link between the materials and instead a simple and 8 rapid, separate removal is ensured. In a purely exemplified manner and as shown, the pack comprises three deep-drawn tablet blisters. The active face is produced with respect to the remaining part of the sealing plate by milling the lat-5 ter. However, any other suitable production process can also be used for producing this face. The punching tool of producing station 15 is provided in a corresponding manner, so that it is possible to punch out packs corresponding to the active face for conveying out of the installation 1, whereas 10 one waste film strip each of the shaping film 11 and the cover film 12, respectively, passes out in accordance with the ladder-like grid shown in Fig. 3. In other words, the overall surface of the sealing punch 22 forms a recess 222 with respect to the active face 221, which, for improving the 15 sealing pressure, is also provided with a per se known corrugation system 223 (this is only shown in the left-hand upper part here, but extends over the entire active face), as well as with heating-free locations 224 corresponding to the recesses 211 of the lower tool part 21. In the case of a 20 plate-like construction of the tools, in the manner shown the corrugation system forms small, pyramidal or frustum-shaped raised portions, so that despite any unevennesses or protuberances possibly existing in the films, the sealing pressure is uniformly exerted and consequently a faultless pack 25 is obtained. However, if roll or roller tools are used, the surface is normally provided with an arrangement of crossing, raised lines for obtaining uniform pressure conditions.

The plate-like sealing tool shown in the drawings and correspondingly designed punching tools permits a continuous, 30 timed production process. However, if it is wished to obtain an untimed, continuous work flow, it is possible to adopt the aforementioned construction of the tools in roller form and 9 then, as for timed operations, the tools are precisely reciprocally controlled with respect to their relative position.

The advantages altogether obtainable with the invention are that separate film waste of clearly defined consistency is 5 obtained, which can be supplied simply and rapidly to a re cycling process solely matched to the particular individual material component and specific thereto, so that a very pure, high quality recycled product is obtained. At least with respect to the marginal areas, it is also possible to reduce 1 o the costs for producing the corrugation which has to be limited to the dimensions of the particular packs. In view of the large number of different pack sizes and the consequent need to keep available the appropriate tools, the latter is very important for the production costs of the in-15 stallation with the tools. However, in particular, the invention makes it completely unnecessary to dispose of the considerable amount of film waste more specifically obtained in the pharmaceutical product packing industry, so that the invention makes an important contribution to the environmen-20 tally friendly design of packing technology.

Claims

-10- Patent Claims

1. Method for producing blister packs of defined volume having a number of shaped nests/cavities for receiving products to be packed in the blister packs, and 5 having a plane surface of a predetermined surface area, comprising the steps of: 10 a) supplying at least two film webs of indefinite length which consist of different materials and comprise a shaping film web as the basis of the blister packs and a cover film web; b) shaping the shaping film web for producing the cavities; c) filling the cavities with the products; d) supplying the cover film web while overlying the 15 shaping film web after filling the cavitites; e) supplying pressure and heat for connecting the webs by sealing them with each other along neighbouring surfaces being in contact with each other; 20 f) dividing the blister packs from the webs; and g) collecting the web portions remaining after the severing of the blister packs from the webs as waste material; characterized in that 25 h) the sealing of the webs occurs exclusively with in an area which, relative to the total area of the webs corresponds to the predetermined surface area of the blister packs to be produced; i) the dividing occurs immediately along the edges formed between the sealed and unsealed sections of the webs such that the plane surface of each of the blister packs has an area equaling the predetermined surface area; and j) the collecting of all such web portions of the cover and of the shaping film webs occurring outside the predetermined surface area is carried out separately. Apparatus for producing blister packs of defined volume having a number of shaped nests/cavities (112) for receiving products (3) to be packed in the blister packs, and having a plane surface of a predetermined surface area, comprising a) a device (111, 121) for supplying at least two film webs (11, 12) of indefinite length which consist of different materials and comprise a shaping film web (11) as the basis of the blister packs and a cover film web (12); b) a device (13) for shaping the shaping film web (11) for producing cavities (112) for receiving the products to be packed; c) a device for filling the cavities (112) in the shaped film web (11) with the products (3); d) a device (121) for supplying the cover film web (12) while covering the shaping film web (11) after the filling of the cavities (112); e) a device (14) for supplying pressure and heat for connecting the webs by sealing them with each other along neighbouring surfaces being in contact with each other, and outside the area of the cavities (112), this device (14) comprising a pair of plate- or roller-like tool parts, which by movement relative to each other receive between them the films forming the pack and carry out the sealing process, of which tool parts ea) a first, preferably lower tool part (21) has at least recesses for receiving the cavities (112) of the shaping film web carrying the products to be packed, and is cooled, and eb) a second, preferably upper tool part (22) has a corrugated surface (223) for exerting pressure and is heatable, ec) the operational face (221) of the second, upper tool part is formed with heating-free locations (224), who, regarding their number, size and arrangement, correspond to the recesses (211) in the lower tool part (21) ; a device (15) for dividing the blister packs from the webs (11, 12); and a collecting device (16) for the severed web portions, which remain outside the predetermined surface area after the severing of the blister packs from the webs, as waste material; characterized in that: the operational face (221) of the second, upper tool part (22) corresponds to the predetermined surface area of the blister packs to be produced; i) the device (15) for dividing the blister packs from the webs is formed such that it divides the blister packs immediately along the edges formed between the sealed and unsealed sections (221 and 222, respectively) of the webs in such a manner that the plane surface of each blister pack has an area equalling that of the predetermined surface area; and j) the collecting device (16) is formed by way of separate collecting devices (161, 162) for separately collecting the waste web portions of the shaping film web (11) and of the cover film web (12), respectively. Apparatus according to claim 2, characterized in that the operational face (221) of the second, upper tool part (22) is formed raised compared with the remaining surface portions (222) thereof. A method substantially as herein described with reference to the accompanying drawings. An apparatus substantially as herein described with reference to the accompanying drawings. F. R. KELLY & CO., AGENTS FOR THE APPLICANTS.