HK1071871B - Security element for security papers and valuable documents - Google Patents

Description

Security element for security papers and documents of value

Technical Field

The invention relates to a security element for security paper, value documents, identity cards or the like, which is of self-supporting design and has two different optically variable security features. The invention furthermore relates to a security paper and to a value document having such a security element.

Background

WO95/10420 describes a value document, which is produced by punching a through-hole, which is then closed on one side by a cover foil which projects beyond the through-hole on all sides. At least a partial area of the cover foil is transparent, so that if there is an attempt to copy the value document, the background is fully displayed and correspondingly reproduced by the copy machine. Furthermore, the cover foil may have a security feature like a hologram.

Disclosure of Invention

The invention proposes a security element, a security paper and a value document which have a higher resistance to forgery than the prior art.

This problem is solved by the features of the independent claims. The object of protection is further developed by the dependent claims.

The security element according to the invention has two security features arranged on opposite sides of the security element, at least one of the security features being optically variable. Optically variable means that the security feature has a different visually recognizable appearance, such as color interlacing from different viewing angles and/or different information.

The optically variable security feature may be, for example: the diffractive structures, optically variable impressions which are observable in reflected light are based exclusively on a rough grid structure of reflective features, thin-film elements or optically variable prints, the printing ink used containing at least one optically variable pigment, such as a liquid crystal pigment or an interference layer pigment. The security element can have any combination of optically variable security features.

The further security feature according to the invention may be any printed image, a translucent or shielded metal layer or the like. The printed image may be formed using any ink, which may also have machine-detectable properties such as luminescent, magnetic or electrically conductive properties.

It is also within the scope of the invention if the security feature comprises readable information which can be read out on the correct side (true to side) on both sides of the security element.

The security element of the invention preferably has two different optically variable security features which are arranged on opposite sides of the security element, so that only one of the optically variable security features is identifiable when the security element is viewed from one side.

The use of the security element according to the invention in security papers or value documents having a through-opening is particularly advantageous. In the document of value described in WO95/10420 according to the prior art, which has a security feature only in the region of the opening, the security feature can be viewed and fully viewed on the correct side only on one side. Viewed from the rear, the security feature cannot be identified at all or is only mirror-symmetrical. However, if the security element according to the invention is arranged in the opening region, a complete and correct security feature can be identified from both sides. This increases the protection against counterfeiting, since the opening, if produced by simple stamping, can be easily manufactured by a counterfeiter. In contrast, the double-sided security feature cannot be simply copied. Especially if there is a textual relationship between the two security features or if the security features represent different views of the same pattern.

For example, the first optically variable security feature may represent a front view of the pattern, such as the face of a eagle or portrait, and the second optically variable security feature may represent the back of the eagle or the back of the head of the portrait. And the two security features are preferably arranged in unison so that a counterfeiter must overcome the additional problem of aligning them. The security feature of the invention provides particular advantages if the security feature comprises readable information, preferably both security features are identical and since the two-layer structure of the security element can always be read from the correct side.

And a machine-detectable layer can be arranged between the security features. This may be at least one infrared absorbing, electrically conducting or magnetic layer. A plurality of such layers may also be arranged between the security features. Moreover, the intermediate layer need not be integral but may be designed to encode or otherwise convey information. In certain cases, it may also be advantageous to arrange an integral color layer, preferably a black layer, between the security features, so that only certain security features are visible from each side of the security element.

According to a preferred embodiment, the security element comprises a plastic foil provided with at least one opaque coating on each side of the plastic foil. Each of the opaque coatings has a discontinuity thereon, preferably in the form of a character, pattern, logo or the like. The discontinuities are arranged offset from one another. That is, in one of the regions having an intermittent opaque coating, the opposite opaque coating is made entirely. This ensures that the security element has only identifiable information on the correct side of each side. The opaque coating is preferably a metal layer, but other coatings such as a colored layer may be used. It is also possible to combine the first security feature consisting of a metallic layer of any colour with the second security feature consisting of an opaque coloured layer or an optically variable printed layer or film coating. Layers or printing inks that appear differently coloured from top and through viewing may also be used.

The metals used may also have different colors and/or be designed to be translucent. If at least one of the layers is translucent, the discontinuity in the opposing layer may also be identifiable under emitted light. This translucency can be created by the thickness of the layer or by using a mask. These possible embodiments of the metal layer can also be used in all other examples of metal layers mentioned hereinafter. The metal layers used are, for example, aluminum, iron, copper, gold, nickel. The term "metal" also refers to any alloy within the scope of the present invention.

The discontinuity may be created by any method, such as laser irradiation, etching methods or cleaning methods.

The provision of such interruptions and their arrangement can of course also be transferred to all other security features with metal layers or other vapor-deposited layers, such as diffractive structures or thin-film elements. Such gaps can also be produced by negative printing if printing inks are used for producing the security features.

According to a further preferred embodiment, when a translucent metal layer is deposited on one side of the security element, the security element can also have a coating with the above-mentioned slits only on the other side.

According to a further preferred embodiment, the security element has two plastic layers in which the diffractive structure is embossed. At least one of the plastic layers is provided with a metal layer, so that the diffractive structure can be observed in reflected light. The second plastic layer may similarly be provided with a metal layer or a dielectric layer with a high reflectivity. If the second plastic layer is also provided with a metal layer, the latter may have a different inherent colour from the first metal layer.

The security element according to the invention does not of course have to be deposited in the region of the opening but can be used advantageously in any position where it can be detected from both sides without being damaged. The location may be, for example, a completely transparent area on the value document, such as a plastic banknote or the like.

Likewise, the security elements according to the invention can be used as security threads, which are incorporated, for example, in so-called "pendulum (pendulum)" window security papers. In the "window area" of such security papers, where the security thread is directly accessible to the surface of the security paper and thus verifiable, it is alternatively provided in front of or behind the paper.

As is well known, it is not always ensured that the security thread is embedded on the correct side of the paper during the paper making process. For a security thread which is wound and combined in a laterally reversed manner (thus being readable), characters, writings, etc. are thus usually provided alternately on the correct side and with the sides reversed. Therefore, regardless of the location of the security thread, a portion is always readable.

In order to reduce this problem, the security element according to the invention can of course also be used even if the security paper has a window area on one side.

The security element can further be used not only to protect security paper or value documents but also to protect any object from being imitated. The same applies to the security paper and/or value document with the security element according to the invention.

The security element can have any contour, for example circular, oval, rectangular, trapezoidal, star-shaped or strip-shaped.

If a security element in the form of a strip is arranged on an open region of a document of value or security paper, a security feature is recognizable over the entire length of the strip, while the second is visible only in the region of the open region.

The production of the security feature is carried out, for example, on a self-supporting carrier element, such as a transparent plastic foil, which is then used as a label material. However, in particular when using diffractive structures as security features, it is either expedient to produce a hot stamped foil, so that the finished layer structure of the security element is produced on a carrier material and then transferred under the action of pressure and heat into at least certain regions of the document of value or security paper. The carrier material is then preferably removed.

The individual security features can also be produced on separate carriers which are then laminated or connected to one another via an adhesive layer.

Drawings

Various embodiments of the present invention will be described in detail below with reference to the following figures, wherein:

figure 1 shows a value document according to the invention;

figure 2 shows a whole cross-sectional view of a value document along the line a-a;

FIG. 3 shows a security element according to one embodiment of the invention;

FIGS. 4-12 illustrate a security element according to further embodiments of the present invention;

FIG. 13 shows a value document according to a further embodiment of the invention;

FIG. 14 shows an example of security paper of the present invention;

fig. 15 shows a cross-sectional view of a security paper taken along line D-D.

Detailed Description

Figure 1 shows a front view of a value document according to the invention. The example represented relates to a banknote 1. The banknote 1 has a through-opening 2 but is covered by a security element 3.

Figure 2 shows a cross-section of the banknote 1 along line a-a. The opening 2 can be clearly identified here. In the example shown, the edges 4 of the opening 2 are shown as smooth, manufactured in a method of punching or cutting the banknote 1. However, if the opening 2 is made in the production of a paper roll for the banknote 1, the edges 4 are irregular and fibrous. Since such an edge cannot be produced later on the paper, the fibrous edge 4 constitutes an additional authenticity feature.

The opening 2 is closed on one side by a security element 3 according to the invention. In the example shown, the security element 3 is arranged in a recess of the banknote around the opening 2. This provides the banknote 1 with a continuous smooth surface which facilitates handling of the banknote, in particular stacking of the banknotes.

According to the invention, the security element 3 has a different appearance when viewed from direction B and when viewed from direction C. In the simplest case, the security element 3 represents different patterns, letters, alphanumeric symbols, figures or combinations of these elements on each side.

However, in order to hinder the imitation of such a security element 3, the two appearances of the security element 3 have a recognizable relationship to one another. For example, both sides may display the same information of the correct side, which is particularly useful in the case of text information, since in this case the text can be read out from both sides as the correct side. Different appearances may also exist if the same information is identified from both sides, which in each case are the correct side.

Alternatively, the security element 3 may also represent different views of a pattern. For example, if a front view of an eagle can be identified from direction B, the back of the eagle can be identified in direction C. The two appearances are preferably in an overprinted arrangement. Likewise, parts of the overall information that complement each other can be arranged overprinted on both sides. Preferably symmetrical information is chosen which is also perceived from the correct side of each side.

By combining two different security features which are arranged in the security element 3 and only one of which is visible to the observer depending on the viewing direction, the security element 3 is given a different appearance.

Fig. 3 shows a security element 3 according to a first embodiment of the invention. It is composed of two different security features 6, 7, each of which in the present case is composed of a diffractive element. The security feature 6 has two plastic layers 8, 9, between which the diffractive structure is arranged in the form of a rugged structure 15. An additional metal layer 12 is provided between the plastic layers 8, 9 to ensure that the information stored in the diffractive structure is identifiable in reflected light. The metal layer may have discontinuities 16 which may have graphical, textual or other alphanumeric characters. The security feature 7 is of similar construction and is composed of two plastic layers 10, 11 with a diffraction structure 17 and a metal layer 13 arranged therebetween. The metal layer 13 may also have discontinuities 18 in the form of any graphic or alphanumeric characters.

If the discontinuities 16, 18 are provided in the metal layers 12, 13, an intermediate layer 23 is preferably provided, which is designed to be opaque, for example white or black, to contrast the metal layers and prevent the mirror-symmetrical properties of the rear side from being seen through. However, the discontinuities may be equally arranged.

The two security features 6, 7 may be interconnected by an adhesive layer or laminated together without an adhesive layer. The security element 3 is finally connected to the banknote 1 by means of an adhesive layer 4.

The plastic layers 9, 11 essentially act as protective layers and are optional. In particular when the overall layer structure is produced on a carrier foil for a transfer material, no plastic layer is required. The carrier foil is in this case covered with a plastic layer 8, which is optionally pre-treated according to its desired release characteristics. The diffractive structure 15 is embossed in said plastic layer 8 and the embossed relief structure 15 is covered by a metal layer 12 preferably formed by a vacuum deposition method. The plastic layer 10 is then overlaid on the metal layer 12 and similarly embossed. The metal layer 13 is preferably applied to the plastic layer 10 by means of vapour deposition to provide the diffractive structure 17. The adhesive layer is applied on the metal layer 13 for transfer to the target substrate. If the metal layers 12, 13 have discontinuities, additional steps using special methods like laser removal, etching or cleaning are required.

The asperities 15 are designed to allow the front face of the eagles to be visible, for example when viewed from direction B, which changes color when the banknote 1 is tilted. However, the diffractive structure 17 produces the described visual effect of the back of a eagle, which also changes colour when the banknote 1 is tilted. Alternatively or additionally, the diffractive structure itself can also contain readable information, which on both sides is the correct side to be readable.

Fig. 4 shows a variant of the security element 3 shown in fig. 3, in which the security features 6, 7 are connected to one another by means of an adhesive layer 19 and metal layers 12, 13 with gaps 16, 18. Adhesive layer 19 may have machine detectable characteristics. It may be, for example, mixed with electrically conductive or magnetic pigments.

Fig. 5 shows a further embodiment of a security element 3 according to the invention. Here again, each security feature 6, 7 consists of two plastic layers 8, 9; 10. 11 with diffractive structures 15, 17 in the form of asperity structures between the plastic layers. But in this case the diffractive structures 15, 17 do not incorporate an opaque metal layer. Instead, the plastic layers 8, 9; 10. 11 have a dielectric layer 20 in between them; 21, said dielectric layer having a dielectric layer with said plastic layer 8, 9; 10. 11 so that the diffractive structures 15, 17 are also visible in reflected light. Since the dielectric layers 20, 21 are transparent, an additional layer must be inserted between the thin-film features 6, 7 to ensure that only one of the thin-film security features 6, 7 is observed in each case. In the example shown, which is an example of black, a black layer 23, since it absorbs the propagating light while increasing the brightness of the visual image of the diffractive structure 15, 17. In the example shown, the security element 3 additionally has an adhesive layer 19 which connects the two security features 6, 7 to one another.

Depending on the adhesive properties or lamination characteristics of the layer 23, the adhesive layer 19 may be omitted.

Instead of the black layer 23, a black magnetic layer can be used to provide the same optical effect and additionally to ensure the machine readability of the security element 3. In addition to the colored layer, the magnetic layer may also be provided to prevent the magnetic layer from being found in transmitted light.

In the variant of the security element 3 shown in fig. 6, the security features 6, 7 are designed differently. The security feature 6 is still comprised of diffractive elements as described in the above figures. In this case, however, the forgery-preventing functional member 7 is composed of a thin film structure 22 which is placed in a certain area and expresses a certain pattern, figure or alphanumeric character. In order to ensure that the two security features 6, 7 are distinguished from one another visually, a black layer 23 is also arranged between the two security features 6, 7. Said layer additionally has the function of increasing the optical effect of the thin-film structure 22 here.

The information represented by the thin-film structure 22 may correspond to the information represented by the diffractive structure 15, supplement it or, as mentioned above, represent different views of the same pattern.

Other performance layers or printing inks containing performance pigments may be used in place of the film structure. The efficiency layer or efficiency pigments can be, for example, luminescent or light-absorbing substances, in particular infrared-absorbing, or liquid-crystal pigments, etc. Ordinary inks are also possible.

Fig. 7 finally shows an embodiment of the security element 3 according to the invention, in which the two security features 6, 7 each consist of an optically variable print 25, 26. The printing inks used therein have at least liquid crystal or interference layer pigments. Different optically variable pigments may be used for the two prints 25, 26.

If in any case only one of the prints 25, 26 is visible, an opaque carrier 24 is used. The carrier 24 is preferably a plastic foil, which is preferably black colored.

Each of the examples shown comprises an adhesive layer 14 which secures the security element 3 to the banknote 1. However, adhesive layer 14 is optional. Instead, the adhesive layer may also be applied on the document itself or a different selected fastening means.

Fig. 8 shows an alternative embodiment of a security element 3 according to the invention. Here, the security feature 6 is arranged on one side of the carrier material 33, which is preferably a transparent plastic foil, and the security feature 7 is arranged on the other side. In the example shown, the security feature 6, 7 consists of a structure which is diffractive in reflected light. The diffractive structure is present in the form of a relief structure on the plastic layers 36, 37, on which the metal layers 35, 38 are respectively provided. Finally, the metal layers 35, 38 are covered with protective layers 34, 39.

In the simplest case, the plastic layers 36, 37 are provided with the same diffractive structure and the security features 6, 7 differ only in the color on the respective metal layer 35, 38. The different colored metal layers 35, 38 may be produced by using special metals having different intrinsic colors. For example, metal layer 35 may be comprised of a layer of silver aluminum and metal layer 38 is comprised of a layer of copper. However, the effect of the different colors of the metal layers can also be produced with the aid of the protective layers 34, 39. In this case, the same material is used for the metal layers 35, 38 and the protective layers 34, 39 are colored with corresponding translucent different colors. Alternatively or additionally, different diffractive structures can also be selected for the security features 6, 7.

Fig. 9 shows a further embodiment of a security element 3 according to the invention, in which different security features 6, 7 are used. The security feature 6 corresponds to the security feature using a diffractive structure on the carrier material 33 as explained above with reference to fig. 8. The security feature 7 is arranged on the opposite side of the carrier material 33 and comprises a printed image 40 covered by a translucent layer 41. The translucent layer 41 may be a thin, translucent, entire metal layer or a shielded metal layer.

Alternatively, a multilayer structure can also be used, which has, for example, a diffractive structure like the security feature 6. In this case, however, the metal layer 35 must be replaced on the one hand by a dielectric transparent layer which embosses the imprint 40 and on the other hand produces a diffractive structure which is visible in reflected light. It is also convenient in this example to color the carrier foil 33 to visually separate the security features 6, 7 from each other. According to a further embodiment of the invention, shown in fig. 10, all layers of the unnecessary security feature are arranged on the same side of the carrier material 33. The translucent layer 41 can thus also be arranged on the same side of the carrier material as the security feature 6. In the example shown here, however, the metal layer 35 has any form of discontinuity. The discontinuity is in the form of a large area having any profile shape. Such as square, circular rectangular or the like. The discontinuity is identifiable in reflected light when the security element 3 is viewed from direction a. The translucent layer 41 arranged underneath the security feature 6 ensures that the print 40 cannot be actually recognized from this viewing direction. The print 40 is only apparent through the discontinuity 42 when viewed under emitted light. However, when the security element is viewed from the direction B, only the print 40 can be easily identified, since the security feature 6 is also hidden here by the translucent layer 41.

Fig. 11 shows a further embodiment of a security element 3 according to the invention. The security feature 6 in this case consists of a plastic layer with a diffraction structure and a metal layer 35 arranged at least in certain regions of the plastic layer. The security feature 7 consists of a print 40 that is visually separated from the security feature 6 by an opaque white printed layer 42.

Fig. 12 finally shows an embodiment of the security element according to the invention, wherein each security feature 6 and the security feature 7 comprises an opaque coating with discontinuities 44, 46 in certain areas. The basic principle is that the opaque coating 45 is free of discontinuities in the area of the discontinuity 44, i.e. it is made integrally in this area. Conversely, the opaque coating 43 is also made in one piece in the region of the discontinuity 46. This ensures that the information represented by the discontinuity 44 in each case is identifiable only from one side of the security element 3 and, in the present case, can always be measured in a correct reading. The opaque coatings 43, 45 may relate to layers of any color and/or metal. The layers 43, 45 can be of different colors, which can therefore also be produced by printing on a further translucent pigmented lacquer layer in the case of a metal layer. Optically variable printing inks or metallic inks can also be applied to the carrier material 33 in the form of a negative print.

If metal layers are used as the opaque coatings 43, 45, they may of course be combined with diffractive structures such as those described above.

In all embodiments using diffractive structures as security features, the structures can also be implemented with transparent diffractive elements by replacing the metal layer with a dielectric layer having a corresponding reflectivity. The dielectric layer can also potentially be a corresponding adhesive layer that serves as an element to attach other security features or the target substrate.

If the security feature has a metal layer, this metal layer can also be translucent or in the form of a barrier metal layer.

Figure 13 shows a further embodiment of the value document according to the invention. In this case, the opening 2 in the banknote 1 is closed by security features 27, 28 on each side. That is to say that in this case the security element 3 is not produced as a homogeneous layer structure and is then arranged in the region of the opening, but rather each individual part of the security element 3, that is to say the security features 27, 28, are arranged separately on one side of the opening. The same security features 6, 7 as described above can be used here. They also exhibit the same optical effect and also have a similar correlation with respect to each other, corresponding to the represented information.

The security element 3 shown in fig. 1 can have any contour, for example it can be round, oval, rectangular, star-shaped, trapezoidal or the like. The contour may be adapted to or match the contour of the opening 2.

Alternatively, the security element 3 can also be embodied in the form of a strip which extends over the entire width or length of the document of value. The use of the embodiment is particularly convenient if a security paper is used for producing the value document and the security element 3 has been applied to the security paper in a continuous form.

Fig. 14 shows a detailed front view of such a security paper 30. The security element 3 is applied at considerable intervals in the form of strips on the paper 30 by means of a continuous hot embossing process. The paper roll 30 is then printed and cut into individual documents in further processing steps.

Figure 15 shows a view through a section of the paper roll 30 along the line D-D. It can be seen that the paper roll 30 has openings 2 at a distance below the security element 3. The openings 2 are preferably cut such that each individual document has an opening 2 therein. Here, the opening 2 has been produced during the production of the roll 30 of paper, so that the edges 31 of said opening 2 are of irregular and fibrous form.

The anti-counterfeiting functional component can also be an anti-counterfeiting line embedded in anti-counterfeiting paper. The security paper in this case preferably has openings, referred to as windows, on both sides.

Claims (31)

1. A security element for security papers, value documents, having at least two different security features arranged on opposite sides of the security element, at least one of the security features being optically visible,

wherein the security features are arranged on the security element such that only one of the security features is identifiable when viewed from one side of the security element, the security features having an identifiable relationship to the represented information.

2. A security element as claimed in claim 1 wherein one of the security features is a printed image or a translucent layer.

3. A security element as claimed in claim 2 in which the translucent layer is a thin metal layer or a shielded metal layer.

4. A security element as claimed in claim 2 or claim 3 in which the printed image has infrared absorbing, luminescent, magnetic or conductive properties.

5. A security element as claimed in at least one of claims 2 to 3, characterized in that the printed image is a negative print.

6. Security element according to at least one of claims 1 to 3, characterized in that the two security features are optically visible security features.

7. A security element according to at least one of claims 1 to 3, characterized in that at least one optically variable security feature is a diffractive structure which is observable in reflected light.

8. A security element as claimed in at least one of claims 1 to 3, characterized in that at least one optically variable security feature is a thin-film element.

9. Security element according to at least one of claims 1 to 3, characterized in that the at least one optically variable security feature is an optically variable print and the printing ink used comprises at least one optically variable pigment.

10. A security element as claimed in claim 9 wherein the optically variable pigment is a liquid crystal pigment or an interference layer pigment.

11. A security element as claimed in at least one of claims 1 to 3, characterized in that a machine-detectable and/or visually detectable layer is arranged between the security features.

12. A security element as claimed in at least one of claims 1 to 3 wherein the visually detectable layer is a luminescent, infrared-absorbing, electrically conductive or magnetic layer.

13. Security element according to at least one of claims 1 to 3, characterized in that a colored layer is arranged between the security features.

14. A security element as claimed in claim 13, characterized in that the coloured layer is a black layer or a white layer

15. A security element as claimed in at least one of claims 1 to 3, characterized in that at least one of the security features has a layer with a discontinuity.

16. A security element as claimed in claim 15 in which the discontinuities are in the form of characters, graphics, logos.

17. A security element according to at least one of claims 1 to 3, characterized in that the security element comprises a structure of a multilayer foil and the different security features are two diffractive structures which are observable in reflected light to produce different optical images.

18. A security element according to claim 17, wherein the at least one diffractive structure observable in reflected light comprises a plastic layer and a metallic layer provided at least in certain areas, said plastic layer having the diffractive structure in the form of a relief structure.

19. A security element as claimed in claim 18, characterized in that the two security features have a plastic layer and a metal layer arranged at least in certain areas, which metal layers exhibit different colour effects.

20. A security element as claimed in claim 17, characterized in that the security element has two security features, between which a magnetic layer is arranged.

21. A security element according to claim 17, wherein at least one of the diffractive structures which is observable in reflected light comprises a plastic layer and a dielectric layer having a refractive index different from that of the plastic layer, whereby the diffractive structure in the form of a relief structure in the plastic layer is observable in reflected light.

22. A security element as claimed in claim 21 having two security features with a black layer disposed therebetween.

23. Security element according to at least one of claims 1 to 3, characterized in that the security feature displays different views under the same pattern.

24. A security element for security papers, value documents, having at least two different security features which are arranged on opposite sides of the security element, each of the security features having an opaque coating with a discontinuity and the opposite opaque coatings being integral in the region of the discontinuity, only one of the security features being identifiable when viewed from one side of the security element, the security features having an identifiable relationship to the represented information.

25. A security element as claimed in claim 24 in which the discontinuities are in the form of letters, graphics, logos.

26. A security element as claimed in claim 24 wherein at least one of the opaque coatings is a metal layer.

27. A security element as claimed in claim 24 or claim 26 in which the opacifying coatings are of different colours.

28. A security paper for the production of value documents, having at least one through-opening, which is closed on one side by a security element according to at least one of claims 1 to 27, so that the different security features are identifiable in the region of the opening.

29. A document of value having at least one through-opening, one side of which is closed by a security element according to at least one of claims 1 to 27, so that the different security features are identifiable in the region of the opening.

30. A value document having at least one through-opening, which is closed on one side by a first optically variable security element and on the opposite side by a second optically variable security element, the security features being different,

wherein the security features are arranged on the security element such that only one of the security features is identifiable when viewed from one side of the security element, the security features having an identifiable relationship to the represented information.

31. A document of value having a security element as claimed in at least one of claims 1 to 27.