GB2617585A - Improved internal label for a bottle - Google Patents

Abstract

An extruded plastics container 10 has a side wall defining a body 12, the container having a first orientation of polymer extrusion. An internal label 20 is positioned within the body, the label comprising a laminated plastics film. The laminated plastics film has at least one outer transparent plastics layer with a second orientation of polymer extrusion. The label has indicia 22 which are viewable through the body and the at least one outer transparent plastics layer. The first and second orientations of polymer extrusion are substantially parallel. The alignment of the polymer extrusions creates polarisation effects whereby the indicia are clearer. A further transparent layer may be added to the opposite side of the label, this further layer having a third orientation of polymer extrusion which is perpendicular to the first and second orientations. When viewed through the opposite side of the container the indicia are obscured by virtue of the perpendicular polarisation caused by the perpendicular extrusion orientations.

Description

IMPROVED INTERNAL LABEL FOR A BOTTLE

FIELD OF THE INVENTION

The present invention provides an improved means for internally labelling containers having some degree of transparency and within which a label is suspended in a fluid, also being to some extent transparent.

BACKGROUND TO THE INVENTION

Bottles containing liquids are normally labelled and labelling is conventionally applied to an outer surface of a bottle. VVhere bottles which are themselves transparent or semitransparent contain liquids, which are transparent or semi-transparent an alternative form of labelling can be applied within the bottle itself. This is a known technique and is disclosed in, for example, US1725199A and W09703887A1, where a label is placed in a bottle against an inner face so as to make it clearly visible through the transparent bottle. This avoids problems with the opacity of the contents of the bottle. However, applying such labels is not readily automated. More recently polymer sheets have been used, for example a printed sheet, which is rolled up, inserted into a bottle and upon resiliently expanding within the bottle, maintains position, either because of its geometry such as in GB2349631A or because of extension of the label into the extremities of the bottle such as in US10370138B2.

Suitable materials for bottles containing consumer goods are known, most are made of plastics materials and include a wide range of polymers such as polyethylene terephthalate, polycarbonate, polystyrene, polyethylene and are the focus of the present disclosure.

Whilst the labelling technique has novelty value and is particularly useful for promotional materials, it has drawbacks. Specifically suspending a label within a liquid is the most conveniently automated, but the separation of label from bottle and intervening fluid has been found to give rise to issues of clarity and readability. Conversely, where such a label contains information that is not intended to be read before consumption (e.g. promotional codes and suchlike) it is difficult to hide such codes or other indicia from the casual observer before consumption (such as may enable the label to be extracted from the bottle so that a hidden portion may be revealed, itself a cumbersome and difficult process). There is therefore a need for an improved format of internal labelling.

SUMMARY OF THE INVENTION

The invention is set out in accordance with the appended claims. In a first embodiment the present invention provides an extruded plastics container having a mouth, a bottom and a continuous wall extending between the mouth and bottom defining a body, the container having a first orientation of polymer extrusion; and an internal label positioned internally within the body comprising a laminated plastics film, the laminated plastics film having at least one outer transparent plastics layer with a second orientation of polymer extrusion through which a visible indicia is viewable through the body and the at least one outer transparent plastics layer; wherein the first and second orientations of polymer extrusion are substantially parallel.

This has been found to give a much clearer and sharper visualisation of the indicia or other image when viewed from outside the container. It has not hitherto been appreciated that the polarisation of light due to the exclusion of the plastics container and of the exclusion or stretching of the plastics films used to make laminates gives rise to a reduction in light intensity and hence perceived clarity of such labels. By aligning the orientation of the polymers such that they are substantially parallel, this effect is substantially diminished and the labels become clearer. It is important to realise that the effect is not "black and white" in most practical situations, and has therefore not previously been appreciated. Particularly when dealing with a clear fluid in the container, the degree of obscuration can have a significant impact upon perception such that an otherwise "pure" spring water may be perceived to be less than "crystal clear" and hence desirable. Effects can be particularly significant for the visually impaired. Effects can also be even more significant in sunny climates where the viewer may be wearing polarised eyewear.

The skilled person will be aware that the laminated plastics film comprises at least one outer transparent plastics layer, and in alternative embodiments, at least one outer transparent plastics layer means more than one layer, i.e. two layers. In this regard, the internal label may be bonded to at least one outer transparent plastics layer, or the internal label may be may be sandwiched between two outer transparent plastics layers.

The visible indicia may be present in the laminated plastics film or it may be at a point further in the container. When further in the container the plastics film must be oriented through the laminated plastics film and have at least one viewing window in the body of the container through which a further portion of the container is visible. This is most relevant where a label is applied (inside or outside) the container so that the inner facing side displays the indicia.

In a second embodiment the present invention provides an extruded plastics container having a mouth, a bottom and a continuous wall extending between the mouth and bottom defining a body, the container having a first orientation of polymer extrusion; and an internal label positioned internally within the body comprising a laminated plastics film, the laminated plastics film having at least one outer transparent plastics layer with a second orientation of polymer extrusion through which a visible indicia is viewable through the body and the at least one outer transparent plastics layer; wherein the first and second orientations of polymer extrusion are substantially perpendicular.

This has been found to give a reduction in light transmission between the label and the viewer. Whilst in itself this may be considered detrimental where a label contains promotional material, such as a QR code which may be scanned to obtain a prize or other consumer benefit, it is important that a label is not clearly visible whilst inside the container, but upon opening the bottle (most beverage containers and the like typically have tamperproof seals) the label can be extracted and be clearly visible. The present invention is preferably used with the container having a tamperproof or tamper evident seal.

The visible indicia may be bonded to, or located adjacent to, one or more of the outer transparent plastics layers. When located further in the container, the laminated plastics film must be oriented to the extent that it comprises a transparent window through which a further portion of the container would otherwise be visible. This is most relevant where a label is applied (inside or outside) the container so that the inner facing side displays the indicia and only on removal of the laminated plastics film (which in this embodiment reduces visibility until removed), such that the rear of the label will then be visible.

The terms 'the first orientation of polymer extrusion' and 'second orientation of polymer extrusion' have been used extensively throughout this application, in connection with the terms 'substantially parallel' and 'substantially perpendicular', for which the skilled person will appreciate that such terms have their usual meaning. When a polymer, colloquially a plastic, such as PET (polyethylene terephthalate), is extended, the polymer chains become oriented.

This is what is meant by orientation of polymer and polymer orientation. Upon extrusion, such as extrusion of a molten polymer film like this for the purposes of producing a container and the subsequent expansion of that extrusion by incoming air to enable the polymer to form a specific container shape with a specific polymer orientation. This orientation is a matter of degree, in other words the invention does not rely on a specific degree of orientation although the higher the level of orientation the better. Similarly, polymer orientation may be achieved by stretching a polymer film, this may be lateral, longitudinal or in some other direction and in doing so the polymer can become orientated. Again, the degree of this orientation is not critical but the greater the degree of orientation the better in terms of realising the invention.

In terms of implementing the present invention, the degree of the elongation of a polymer affects the degree of polymer orientation. The greater the degree of elongation then the greater the degree of polymer orientation (which usually plateaus after a degree of elongation). In practical terms this means that for material such as polyethylene or polyethylene terephthalate, a degree of elongation in the order of stretching (termed a draw ratio) by a factor of 2.5 to 3.0 can give the polymer orientation and further elongation can continue this orientation but to a lesser degree. The specific polymer and fluidity of the polymer upon extension can affect these ratios and the skilled person will be to determine the most effective parameters for a given material. Similarly, the speed of drawing (extension) can also affect the degree of orientation.

At this point it is reiterated that for the invention to realise the benefit it is not necessary for large transitions in light transmission to occur providing that some level occurs as even a small diminution in light can give a noticeable effect, such as in the perception of quality noted by a consumer.

In the present invention, the term 'parallel' takes on its normal meaning as does the term substantially parallel', which to some extent depends upon the degree of polymer orientation, a high degree of parallelism or all orthogonal orientation may be required where the degree of polymer orientation is limited, so for example the difference in orientation in the order of up to 5°. However, for a strongly orientated polymer the benefits of the invention may be realised where the offset from an ideal is in the range of up to 10°. Parallelism and orthogonal orientation may preferably be within 1° accuracy. This is realistically achieved as the longitudinal axis of an extruded bottle generally conforms to the polymer orientation, and similarly for a film, and therefore the two components of the invention may be readily combined. The invention is preferably performed using a label in the form of a laminated plastics film in which physical extremities in the film are configured to engage with internal features of the bottle. Preferred features are the neck of the container and the base (which is typically bowed inwards) of the container.

A third embodiment of the present invention provides an extruded plastics container being transparent or semi-transparent, an internal label for said container bearing an indicia having a colour, and a fluid contained within the container and substantially filling the container, the fluid having a colour which is the same or substantially the same as the indicia and the label being located in the fluid away from the walls of the container.

The indicia are thus obscured whilst there is fluid in the container. This enables the indicia to carry information, such as promotional codes and suchlike which are not desired to be communicated to the user until after consumption of the product. This enables the indicia to carry information which is only made available to a user upon emptying, for example by drinking the contents of, the container. Internal labels preferably comprise indicia not having the same or similar colour to the liquid such that that portion of the indicia will be visible, and therefore convey information, whilst the bottle retains its contents.

The embodiments of the present invention are combinable.

In a preferred combination a first side of the internal label has a polymer film comprising a first orientation of polymer extrusion and a second side of the internal label has a polymer film comprising a second perpendicular orientation of polymer extrusion such that one side is more clearly visible through the container than the other side. This enables one side of the internal label to comprise information which is intended to be viewed, and a second, reverse, side of the internal label to comprise information which is not intended to be viewed (read) whilst the label is located within the container.

In practical terms since a suitable container for use in the present invention is an extruded polyethylene terephthalate soft drinks bottle, the first orientation of polymer extrusion of the container corresponds to a longitudinal orientation of extrusion, with the first side of the internal label having a second parallel orientation of polymer extrusion such that the indicia of the internal label are clearly visible and the reverse side of the internal label has a perpendicular polymer orientation such that the visibility of the indicia of the label is reduced. The first side may for example be suitable for carrying information regarding the soft drink, such as a name and dietary information and the second side may for example comprise promotional material intended to be used after consuming the bottle contents. Preferably the second side comprises information regarding recycling, such that on emptying of the bottle suitable directions from recycling are made visible.

In a further preferred combination, the internal label comprises a polymer film having an orientation of polymer extrusion which is perpendicular to the orientation of polymer extrusion of the bottle, and the internal label comprises information not intended to be viewed (read) whilst a coloured contents of the bottle are present, the contents being a fluid of the same or similar colour to the indicia or part of the indicia of the internal label.

The following applies to all embodiments This provides improved obscuration of information and therefore it is not necessary that either the effect from the perpendicular orientation of the films or from the fluid, be completely effective but in combination all obscuration whilst the label is within the bottle of coloured fluid is sufficient to obscure information not intended to be viewed (read) whilst the label remains within the bottle.

The degree of orientation of polymer extrusion can be qualitatively determined using spectroscopy. Spectroscopy methods utilising polarised radiation, visible or infrared may be suitable. Spectroscopy using polarised visible radiation is preferred.

The mechanism of measurement is important because absorption occurs only for dipole moment changes that are perpendicular to the light path. For normal transmission measurements, this means that vibrations with dipole moment changes in the plane of the film may be determined. A polarizer is used to confine the electric field of the light to a single direction perpendicular to the direction of propagation, so as to measure absorptions in the machine and transverse direction. This approach enables the ratio of the absorbances in the two directions, the dichroic ratio, to be determined. This allows a measure of the degree of orientation in the plane of the film to be determined.

The wavelength at which the measurement takes place will typically be at a wavelength at which the dichroic effect is most prominent, for example with polyethylene a wavelength of 710 cm-1 would be suitable, a non-orientated film or bottle has a dichroic ratio of approximately 1.0, whereas an orientated polymer film will have a ratio above 1 and in the order of 2.

In a preferred embodiment of the present invention the combination with a coloured liquid and perpendicularly orientated polymer films all utilises a fluid having an absorption wavelength equal to or substantially equal to the wavelength at which the dichroic ratio is one or more compared to other wavelengths. An example is polyethylene, and the optimum wavelength is in the order of 710 cm-I, which is in the red region of the spectrum. However, it is not necessary to use a wavelength in the visible range for the determination of polymer orientation as it may be convenient to use wavelengths outside the visible spectrum, such as to avoid interference by visible light in measurement therefore, for example a measurement at 1410 cm-' for the dichroic ratio has been found suitable for polyethylene terephthalate (PET).

In the present invention, the dichroic ratio of the polymer used for the container and for at least one of the polymer films is greater than 1.25. Above this value, the effect becomes increasingly prominent although even at lower levels perceptible effects can be seen, which can be particularly significant when dealing with fluids which are intended to be "crystal clear". A preferred range of dichroic ratio is 1.5 to 5.0, as very high levels of dichroic ratio tend to be associated with birefringence effects which make attractive visual effects which distract the viewer for perceiving an indicia.

In the present invention wherein the first and second orientations of polymer extrusion are substantially perpendicular the preferred range of decorative ratio is 2.5 to 10.0, since birefringence may give further obscuration, the upper limit is determined by a tendency for such columns to become very highly orientated and therefore have dimensional weaknesses (such as splitting) along the length of the orientation.

The container is preferably formed by extrusion. More preferably the container is formed by blow moulding so as to increase orientation alongside extrusion into the mould.

The container is preferably a bottle, the bottle is preferably a sealed bottle, the sealed bottle preferably comprises a carbonated soft drink as the fluid such as carbonated water.

The fluid is preferably a liquid, the liquid is preferably water, the water is preferably carbonated and under pressure. This provides the absence of gas bubbles in the sealed state in addition to a mark of whether the container has been opened, such as to extract its contents.

The fluid preferably has dissolved solids in it. This increases the refractive index of the fluid and increases the effect of the invention. The refractive index of the fluid is preferably 1.33, more preferably greater than 1.40.

The fluid is preferably coloured yellow, orange or brown and the indicia is preferably comprising the same or substantially the same (such as within +/-20 nm of peak absorbance) colour.

The above characteristics of the fluid are combinable and are disclosed as such. Hence, the fluid may be water based, having dissolved solids, such as sucrose or glucose, be carbonated and be clear, coloured yellow or brown.

The indicia is preferably text, the text is preferably a code or serial number providing access to goods or service of value.

The plastic container and the laminated plastics film are polymers preferably selected from one or more of high-density polyethylene (HOPE), low-density polyethylene (LOPE), polystyrene, polyethylene terephthalate (PET) and copolymers thereof.

HOPE is a thermoplastic polymer produced from the monomer ethylene. HOPE is known for its high strength-to-density ratio. The density of HOPE ranges from 0.93 to 0.97 g/cm3. Although the density of HDPE is only marginally higher than that of low-density polyethylene, HOPE has little branching, giving it stronger intermolecular forces and tensile strength (38 MPa versus 21 MPa) than LOPE. The difference in strength exceeds the difference in density, giving HOPE a higher specific strength. It is also harder, more opaque and can withstand somewhat higher temperatures (120 °C/248 °F for shorter periods). HOPE is resistant to many different solvents, so it cannot be glued, pipe joints must be made by welding, but this makes objects constructed out of HOPE ideally suited for transporting drinking water and waste water (storm and sewage). LOPE is a thermoplastic also made from the monomer ethylene.

LOPE is defined by a density range of 0.917 to 0.93 g/cm3. At room temperature it is not reactive, except to strong oxidizers; some solvents cause it to swell. It can withstand temperatures of 65 °C (149 °F) continuously and 90 °C (194 °F) for a short time. Made in translucent and opaque variations, it is quite flexible and tough. LDPE has more branching (on about 2% of the carbon atoms) than HOPE, so its intermolecular forces (instantaneous-dipole induced-dipole attraction) are weaker, its tensile strength is lower, and its resilience is higher. The side branches mean that its molecules are less tightly packed and less crystalline, and therefore its density is lower. When exposed to consistent sunlight, the plastic produces significant amounts of two greenhouse gases: methane and ethylene. Because of its lower density (high branching), it breaks down more easily than other plastics; as this happens, the surface area increases. Production of these trace gases from virgin plastics increases with surface area and with time, so that LDPE emits greenhouse gases at a more unsustainable rate than other plastics. When incubated in air, LDPE emits methane and ethylene at rates about 2 times and about 76 times, respectively, more than in water.

Polystyrene is a synthetic aromatic hydrocarbon polymer made from the monomer known as styrene, and can be solid or foamed. General-purpose polystyrene is clear, hard, and brittle, and is an inexpensive resin per unit weight. It is a poor barrier to oxygen and water vapour and has a relatively low melting point. Polystyrene is one of the most widely used plastics, the scale of its production being several million tonnes per year. Polystyrene can be naturally transparent, but can be coloured with colourants. Uses include protective packaging (such as packing peanuts and in jewel cases used for storage of optical discs such as CDs and occasionally DVD5), containers, lids, bottles, trays, tumblers, disposable cutlery, in the making of models, and as an alternative material for phonograph records. As a thermoplastic polymer, polystyrene is in a solid (glassy) state at room temperature but flows if heated above about 100 °C, its glass transition temperature. It becomes rigid again when cooled. This temperature behaviour is exploited for extrusion and also for moulding and vacuum forming, since it can be cast into moulds with fine detail.

PET is a clear, strong, and lightweight plastic that is widely used for packaging foods and beverages, especially convenience-sized soft drinks, juices and water.

The polymer is more preferably PET or LDPE. These provide clearer effects with the present invention. PET is most preferred as it can be easily oriented by both extension and extrusion. Most preferably, the plastics container is formed from PET and the internal label is formed from polyethylene, being either low or high density.

The polymer film is preferably stretched to orientate the polymer. Stretching may be in a lateral or longitudinal direction.

The indicia is preferably sandwiched in the laminated plastics film, at least one side of which must comprise the polymer film. This seals the inks and thus increases compatibility with foodstuffs. Alternatively, both sides may comprise the laminated plastics film.

The indicia is preferably printed upon the plastics film. The printing is preferably before lamination. This seals in the print due to the heat of the lamination process and increases its durability.

The laminate is preferably thermally formed by pressing polymer films together at a raised temperature, such as at above the glass transition point of the polymer. The polymer in the aqueous polymer dispersion may have a glass transition temperature (Tg) less than 0 °C, for example, from -100 °C to 0 °C, from -70 °C to -5 °C, from -65 °C to -10 °C, from -60 °C to - °C, or from -60 °C to -20 °C. The particular Tg values reported herein are those measured by differential scanning calorimetry (DSC) according to ASTM D3418-12 (2012) Standard Test Method for Transition Temperatures and Enthalpies of Fusion and Crystallization of Polymers by Differential Scanning Calorimetry. A 5-10 milligram (mg) sample can be analyzed in an open aluminum pan on a TA Instrument DSC Q2000 fitted with an auto-sampler under nitrogen atmosphere. Tg measurement by DSC is with from -90 °C to 150 °C, 20 °C/min; 2 cycles. The Tg was measured at the midpoint of the inflection obtained in the 2nd cycle using the half height method.

The layers of the laminated plastics film preferably comprise the same plastic material, this reduces distortion of the label, such as by curling.

The layers of the laminated plastics film preferably are of the same thickness of, this reduces distortion, such as by crinkling.

DESCRIPTION OF THE INVENTION

The present invention will now be illustrated by way of the following schematic drawings in which like numerals are intended to represent like features, and in which: Figure 1 shows a bottle comprising an internal label with the bottle and label having orientations of polymer extrusion which are substantially parallel; Figure 2 shows a bottle comprising an internal label with the bottle and label having orientations of polymer extrusion which are substantially perpendicular; Figure 3 shows a schematic of polymer orientation; Figure 4 shows a schematic of blow moulding; Figure 5 shows a schematic of an internal label comprising a laminated plastics film; and Figure 6 shows a lateral view of an internal label.

Figure 1 shows a bottle 10, containing a label 20, the bottle having a first orientation of polymer extrusion as indicated by the vertical arrow and the label having a second orientation of polymer extrusion as indicated by the further vertical arrows. The orientations of polymer extrusion are substantially parallel. Upon the label are placed indicia 22 such that the indicia may be viewed through a transparent wall in the body 12 of the bottle.

Figure 2 shows a bottle 10, containing a label 20, the bottle having a first orientation of polymer extrusion as indicated by the vertical arrow and the label having a second orientation of polymer extrusion as indicated by the horizontal arrows. The orientations of polymer extrusion are substantially perpendicular. Upon the label are placed indicia 24 such that the indicia may be viewed through a transparent wall in the body 14 of the bottle.

Figure 3 shows a notional polymer configuration, in the upper portion of the figure showing an unaligned polymer in which there is substantial irregularity in the chain, such polymers show minimum dichroic effects. Below that is a schematic of an aligned polymer, the polymer is not completely aligned as such, the material, is obtained by stretching, extruding or otherwise extending the polymeric material give rise to dichroic effects in terms of the present invention.

Figure 4 is a schematic of blow moulding a container for the present invention, initially a slug 6 is extruded, by elongation to form a closed two tubular structure 8, which is then pressed into the structure so that the structure expands and extends further, to provide a finished container 10. This is a preferred process for manufacturing a container suitable for the present invention, the preferred form of container being a bottle. A further preferred container is an elongate bottle.

Figure 5 shows a schematic of a label for use in the present invention, this particular form of label illustrated is of a combination type as described earlier in which both aspects of the invention are simultaneously present. The label comprises a first polymer film 22 having a vertical, (second), polymer alignment and a second polymer film 24 having a (third) polymer alignment perpendicular to that of the first film. Such a label is placed in a container (not shown) which will have a first polymer orientation/alignment. Between the polymer films is placed indicia (here shown as a smiley face). The indicia will be visible with minimal degradation visibility through a clear or substantially clear container 10 into which the label 20 is placed as the orientations of first and second polymer alignments are substantially parallel. However, the second polymer film having a substantially orthogonal alignment will be to some extent obscured. The illustrative indicia will be clearly visible from the rear through the second polymer film when the label is taken out of the bottle 10. The indicia may be placed on the film by transfer printing or may be present as a separate physical item, such as a piece of printed card (for example printed front and back) one equivalent piece of polymer film or sheet.

Figure 6 is a lateral view of the label and exploded form in which the label 20 comprises a front polymer sheet 22, a rear polymer sheet 24 and indicia 26 (here in physical form) present on a backing element (such as a sheet of polymer film) and having indicia on a front side 26F and indicia on a rearside 26B. This figure is to be read in conjunction with figure 5 and as such when looking through the front of the container in the invention, i.e. through body 12, indicia 26F will be clearly visible whereas when looking through the rear body 14 of the container indicia 26B will be less clearly visible and is preferably obscured. This form of label is preferably used in the present invention in combination with a fluid in the container having a degree of colouration, that degree of colouration coinciding with that of indicia 26B to make it less visible and deviating from that coloration in indicia 26F to make it more visible.

Claims (12)

1. CLAIMS: 1. An extruded plastics container having a mouth, a bottom and a continuous wall extending between the mouth and bottom defining a body, the container having a first orientation of polymer extrusion; and an internal label positioned internally within the body comprising a laminated plastics film, the laminated plastics film having at least one outer transparent plastics layer with a second orientation of polymer extrusion through which a visible indicia is viewable through the body and the at least one outer transparent plastics layer; wherein the first and second orientations of polymer extrusion are substantially parallel.
2. 2. The container of claim 1, wherein the container is formed by blow moulding.
3. 3. The container of claim 1 or claim 2, wherein the container is a bottle of extruded polyethylene terephthalate.
4. 4. The container of any of claim 1 to claim 3, wherein the container is a bottle comprising a fluid which is carbonated water.
5. 5. The container of claim 4, wherein the fluid comprises dissolved solids.
6. 6. The container of any preceding claim, wherein the dichroic ratio of the first and second orientations of polymer extrusion is 1.1 or greater.
7. 7. The container of any preceding claim, wherein the dichroic ratio of the first and second orientations of polymer extrusion is in the range 1.25 to 5.0.
8. 8. The container of any preceding claim, wherein the laminated plastics film has the same polymer orientation for each of the polymer layers.
9. 9. The container of any preceding claim, wherein the laminated plastics film comprises a first polymer layer, a visible printed indicia and a second polymer layer.
10. 10. The container of any preceding claim, wherein the laminated plastics film consists of a first polymer layer, a visible printed indicia and a second polymer layer.
11. 11. The container of any of claim 4 to claim 10, wherein the fluid is clear.
12. 12. The container of any of claim 4 to claim 11, wherein the fluid is the same or substantially the same colour as a part of the indicia.