[0001] The present invention relates to a liquid package for pressurized contents.
[0002] A demand has existed for a long time for inexpensive and ecologically beneficial
packages for pressurized, carbonated beverages. The packages found on the market to-day
are glass bottles, aluminium cans and plastic bottles. Each of these has some advantages
and disadvantages.
[0003] Glass has good properties permitting a gas-tight package which withstands the inner
pressure the contents exercise on the package and which does not affect the taste
of the liquid contents. Glass bottles can be cleaned and refilled or crushed when
the raw material is to be used anew for bottle manufacture. To wash and refill may
be considered advantageous but the washing process entails undesirable expense and
an appreciable consumption of energy. Conventional glass bottles, moreover, are heavy
and require a large volume in transport. The weight makes them also less attractive
for the consumer.
[0004] The aluminium cans discussed in recent times, are also eminently suitable for recycling.
The main disadvantage of aluminium as packing material, however, is the expensive
and energy-demanding manufacture of aluminium, which also tends to become more expensive
still with rising energy prices. A further disadvantage of this type of packages is
that their inside are varnished and that this varnish contains solvents which negatively
affect the taste of the liquid. Furthermore, empty packages which are transproted
to the brewery cannot be stacked into one another, so that the transport becomes inefficient
and expensive.
[0005] Plastic bottles which are also encountered on the market for carbonated beverages
are expensive. The plastic raw material may be reused, however, for another manufacture,
such as e.g. insulating padding in clothing.
[0006] For a development of a wholly new packaging for pressurized contents all the abovementioned
aspects have to be weighed up carefully. The packaging should be inexpensive and the
manu facture should not be too energy-demanding or require an expensive raw material.
The package should be recoverable. Moreover, it should be light from a point of view
of the consumer and of transport and, in particular, it should be stackable for a
more efficient transport in empty state. The packing material should protect the product
and it should not affect its taste and quality. The material also should be gas-tight
and withstand the internal pressure which the liquid exercises on the package.
[0007] It is an object of the present invention to make possible the manufacture of a cheaper
and ecologically more beneficial package for pressurized contents which possesses
the properties enumerated above.
[0008] It is a further object of the present invention to provide a package where the contents
are in contact with a thermoplastic material which, differently from varnish, does
not affect the quality of the liquid contents and in which the liquid is protected
from light, which also contributes to the retention of the quality and taste of the
liquid contents.
[0009] It is a further object of the present invention to provide the package with a characteristic
and attractive appearance in a form which contributes to a good utilization of volume
during distribution.
[0010] These and other objects have been achieved in accordance with the invention in that
a liquid package of the type described in the introduction has been given the characteristic
that the package is in the shape of a truncated cone where the relationship between
top radius and bottom radius can be expressed by the formula r ≈ 0.4R, where r designates
the radius of the top surface and R designates the radius of the bottom surface.
[0011] The invention will now be described in more detail with reference to the attached
drawings wherein
Fig.1 shows the packages as whole
Fig.2 shows the relationship between the top radius and the bottom radius
Fig.3 shows a conceivable packing pattern as a distribution unit.
[0012] As is evident from Fig.1 the package 1 in accordance with the present invention is
in the shape of a truncated cone, with a shell surface 2 manufactured from a thin
metal foil,e.g. thin sheet steel, laminated at least on one side with a thermoplastic
material. The metal foil has good gas-tightness properties. The thermoplastic material
is chosen so that it has good welding characteristics. Moreover, it should have good
adhesion capacity to metal and it should be ecologically beneficial. If a choice is
made to manufacture the shell surface 2 of thin sheet steel, it is possible already
from the start to make use in the manufacture of recycled scrap and thus make the
manufacture less expensive. The sheet steel too may possibly be recovered.
[0013] The stamped out sheet is rolled round to a cone and the thermoplastic material on
its surface is welded with overlap to a longitudinal joint 3. The joint 3 coincides
with a generatrix on the truncated cone.
[0014] The package 1 is provided with bottom 4 and top 5. The bottom 4, which may be manufactured
of thermoplastics or sheet metal, may be wholly closed or it may comprise an opening
device. The bottom 4 should be designed so that it can withstand the pressure from
the enclosed liquid. If it is chosen to make the bottom 4 of sheet metal it should
be covered at least on one side by means of lamination with, or application of, a
thermoplastic material and be welded together with the thermoplastic layer of the
shell surface 2 by heating.
[0015] To the top 5 or bottom 4 an opening device 6 is fitted in a tight manner which on
opening of the package 1 is intended to be torn off so that the enclosed liquid becomes
accessible for consumption.
[0016] The truncated cone is characterized by the relationship between the radii of its
top and bottom surfaces which can be expressed by the formula r = (√2 - 1) R, which
corresponds to ≈ 0.4R, where R designates the radius of the top surface 7 and R the
radius of the bottom surface 8, which is illustrated in Fig.2.
[0017] The bottom radius is chosen so that it fits the module used in the handling of distribution
and transport. The top radius then can be calculated according to the aforementioned
formula r = (√2 - 1)R. The height of the package, and with it also the cone angle,
is determined by the volume, bearing in mind the product volume, head space, that
is to say splash space, and bottom and top design. The height, and the cone angle
connected therewith, are limited by practical considerations in respect of the ease
of handling and the desire that the packages should make the best possible use of
the distribution units. The enclosed volume is calculated by the formula

R² (3 - √2) where H represents the height and R the radius of the bottom area 8.
[0018] Fig.3 shows a distribution unit 9 comprising 13 off packages 1,10. With different
package dimensions, of course, a great number of other packing patterns may exist
taking into consideration the transport and distribution modules.
[0019] Fig.3 demonstrates also that if a package 10 with an aforementioned relationship
between the radii of top and bottom surfaces is positioned upside down, that is to
say reversed between 4 adjoining packages 1 positioned the right way up, the reversed
package 10 will rest on its top surface 7, that is to say wholly on a level with the
bottom surfaces 8 of the four packages 1 which are positioned the right way up. At
the same time a tangential touch is obtained along four whole generatrices on the
shell surface 2 of the reversed package 10 and one whole generatrix on each shell
surface 2 of the four packages 1 which are positioned the right way up. Thus a good
utilization is obtained of the space which the packages 1 occupy in their distribution
unit 9. The packing pattern is held together e.g. by being shrink-wrapped or enclosed,
in some form, by the distribution unit. To hold the units 9 together the space can
be utilized better, moreover, by turning every other unit 9 upside down. The units
9 can also be stacked in vertical direction, since their surfaces are wholly plane
and the internal pressure of the packages 1 imparts to them great strength and endurance
against the effect of external pressure.
[0020] As is evident from the above description, a liquid package is provided by the present
invention which complies with the demands regarding gas tightness and strength for
carbonated beverages and which is cheaper than the liquid packages for pressurized
contents on the market at present. The liquid packages in accordance with the present
invention, moreover, are ecologically more beneficial, since they can be manufactured
mainly from recycled material which can be recovered again. The manufacture, moreover,
is not as energy-demanding as e.g. that of aluminium cans. By means of the present
invention, moreover, a package is obtained which in an improved manner preserves the
quality and taste of the enclosed beverage, as the enclosed beverage is in contact
with a thermoplastic material and as it is protected against light by the metal foil.
1. A liquid package for pressurized contents,
characterized in that the package is in the shape of a truncated cone, where the relationship between top
radius and bottom radius can be expressed by the formula r ≈ 0.4R, where r designates
the radius of the top surface 7 and R designates the radius of the bottom surface
8.
2. A liquid package 1 for pressurized contents in accordance with claim 1,
characterized in that a package 10, placed in reversed position between four packages 1 which adjoin one
another and are positioned the right way up, touches along four generatrices of its
shell surface 2, tangentially, one generatrix on the shell surfaces 2 of each of the
four packages positioned the right way up, and that the top surface 7 of the reversed
package 10 is wholly on a level with the bottom surfaces 8 of the four packages 1
positioned the right way up.
3. A liquid package 1 for pressurized contents in accordance with claim 1,
characterized in that the shell surface 2 of the package 1 is manufactured from thin metal foil, laminated
at least on one side with a thermoplastic material, and that the package is provided
with top 5 and bottom 4.
4. A liquid package 1 for pressurized contents in accordance with claim 1,
characterized in that the top 5 or the bottom 4 of the package comprises an opening device 6 which is fitted
in a tight manner to the package 1 and is intended to be torn off wholly or partly
on opening of the package 1.