DE2416495A1 - PLASTIC BAG - Google Patents

Description

PATENT ANWALTSBÜRO TlEDTKE » ^J BüHUNG - KlNNE 2416495

TEL. (089) 539B53-56 TEL2X: 52-845 tipa »CAbLE ADDI.ESS: Garmaniapatent Munich

8000 Munich 2

Bavariaring 4

P.O. Box 202403 April 4, 1974 B 5925

Imperial Chemical Industries Limited London, UK

Plastic bags

The invention relates to a plastic film or plastic film bag, and more particularly to one Plastic bags for handling or processing liquids.

When yoghurt is produced at home, there is a risk that undesirable strains of fermentation organisms will penetrate, in particular those from previous home crops, so that the product is given an inferior taste Q ₃ or a bad aroma. It is therefore advisable to ο use freshly procured cultures ο for each fermentation operation. However, this difficulty can be avoided, right? considerably by allowing the fermentation process to proceed under conditions which are essentially sterile with respect to the culture organisms. In this way, the home culture can be used repeatedly for at least a period of time,

(Munich) Account 51/61 070 Dresdner Bank (Munich) loo. 3939 844 Postscheck (Munich) loo. 670 43-804

without any significant deterioration in taste.

The equipment necessary for the production of yoghurt consists essentially only of a thermally insulated one Container and a thermometer. The container advantageously consists of an outer rigid insulated container and a plastic film liner, keep their necks closed for most of the time required to complete the process can.

The invention provides a plastic bag which can function as such a liner, as well as a cover ^τ for the thermometer, by means of which contamination of the culture can be substantially avoided or at least considerably reduced compared to the usual home cultivation methods.

The invention thus provides a plastic bag with an elongated, integral part, which is sealed off from the bag and from this sheath detachable by tearing off; the bag and the cover are thus closed on all sides, the pouch having a tear line at one end along which it can be torn open to form a pouch opening; the elongated shell likewise has a section in its wall which can be torn open to form an opening.

The tear line is preferably a line of perforations through the front and back of the bag so that the end section can be torn off. Even in the case of long

509820/0289

In the elongated envelope, the frangible portion of the wall is best defined by a line or pattern of perforations; this part is preferably located near one end of the envelope. A perforation line can be provided in the same way to allow the elongate envelope to be separated from the bag; this line can at the same time the Form tear line along which the bag wall can be torn to form the bag opening.

The perforations can be sealed around their edges by using heated needles or pins formed v / earth. However, this is generally unnecessary because bags have tear lines from unsealed perforations there is generally sufficient security against contamination, provided that these bags are otherwise exposed to the atmosphere are sealed.

The invention is explained in more detail below with reference to schematic drawings of several exemplary embodiments.

Figure 1 is a top plan view of a preferred embodiment of the plastic bag, which is produced in a continuous process from a Length of lay-flat tubular film was produced;

Figure 2 is a top plan view of an alternative embodiment of the pouch also shown in FIG

5 09820/0289

Tubular film was formed;

Figures 3 to 5 show the use of the elongated envelope as a thermometer envelope;

Figure 6 shows a filled bag in use as a liner in an insulated container.

In FIG. 1, the reference numeral 1 denotes an edge fold of a tubular film laid flat; 2 is one in the manufacturing direction running sealing seam formed by the action of heat, which is continuous between the opposing Walls of the tubular film was formed; 3 is a line of perforations running in the machine direction, the were formed continuously; 4 is a bead seal forming a side seal of the bag, with the side seals adjacent pouches can be formed simultaneously by the previous bag separated from the tubular film web and for this purpose the tubular film with the help of a heated knife is severed. 5 is an array of short lines from perforations, which also run in the direction of production and extend through both walls of the tubular film, the lines from the next following in the longitudinal direction are at such a distance that they by transverse seals in the tubular film (i.e. the seals forming two side seals 4) are halved as shown. At the finished bag, 6 is the actual bag, which can be torn open along the tear line 3 in order to close a bag opening

509820/0289

create and at the same time separate the elongated envelope 7 from the bag. Through the perforations of line 5 is a tearable portion of the viand of the elongated envelope 7 is created.

In FIG. 2, 1 in turn denotes an edge fold of the tubular film laid flat and 3 denotes one in the production direction running perforation line. 8 is a transverse line of perforations formed between a pair of transverse seals 9 which connect the two walls of the tubular film to one another in a sealing manner. 10 is one of the two bead seals that go through Cut the tubular film with the help of a heated knife are formed, at the same time the bag is separated from the tubular film. In the finished bag, 11 is the actual one Bag 12 and 12 the elongated envelope which can be separated by tearing along the perforated tear line 8. the Tear line 3 provides a means for opening the bag 11 and a frangible portion of the wall of the envelope 12.

Of the bags shown in Figures 1 and 2, that of Figure 1 is generally preferred because the Longitudinal alignment of the tear lines eliminates the risk of tearing due to longitudinal tension in the bag during manufacture the tubular film web occurs.

FIGS. 3 to 5 show stages in the use of the elongated casing 7 according to FIG. 1 to form a casing for a thermometer 13. The closed end of the sheath becomes

509820/0289

pushed in by the bulb of the thermometer and progressing everted until the bulb of the thermometer is encircled by the closed end of the sheath from the other end which is torn open along line 5, this process continuing until the entire envelope or the required length has been turned inside out on the thermometer to form a cover. the The envelope formed in this way has an outer surface which is sterile for the purpose of the invention. That in the wrapper The existing thermometer can then be used to measure the temperature of the milk before the yogurt culture is introduced and, if necessary, also for stirring the culture into the milk.

Fig. 6 shows the bag in use as a liner containing milk 14 contained in the thermally insulating Container 15 is subjected to fermentation. The neck of the bag 16 is laid flat and longitudinally has been folded and is kept closed by the lid 17 and the screw cap 18 of the container.

Polyethylene film is particularly suitable as a suitable film for making bags. Its thickness should be chosen so that the elongated sheath can be everted around the thermometer without difficulty and quickly can be collapsed in close contact with the thermometer when immersed in the liquid. For typical cases the film will be about 30 mum thick. For easy turning inside out

B09820 / 0289

Thermometer envelope, the film preferably has a low coefficient of static friction, ie on the order of μ - ^ 0.25. The size of the bag is chosen depending on the intended use. For normal household use, a bag dimension of about 195 mm 300 mm and for the envelope a dimension of 45 mm χ 300 mm is generally suitable,

The bags shown in the drawings were made from tubular film; of course he can Bag according to the invention can also be made from two separate webs of film by suitably welding seams and Tear lines are arranged. If necessary, gussets can be arranged in particular at the bottom of the bag according to FIG. 1.

In addition, in addition to being used for the production of yoghurt, the bag can of course also be used for other purposes Process for the biological treatment of liquids under controlled temperature and one essentially of impurities free environment.

The invention thus provides a plastic bag for treating or processing liquids with a thus one-piece tear-off cover for a thermometer, the bag being closed on all sides and along a tear line can be opened.

509820/0289

Claims (2)

Claims f 1. j Bag made of plastic film for the processing of liquids, characterized by a closed, one-piece cover (7) which can be separated from the bag (6) by being torn off, the bag and cover being closed on all sides and the bag has at one end a tear line (3) along which it can be torn open in order to obtain an opening for the bag, and wherein part of the wall of the elongate envelope (7) is also tearable in order to obtain a passage opening. 2. Bag according to claim 1, characterized in that it is formed by a tubular film and the tear line (3) runs parallel to the direction of manufacture of the film. 509820/0289 Blank page