Document with covert security features and method of manufacturing it

Abstract

A passport, or other ID or security document, (1) comprises a plurality of bound pages including a cover page (10) and at least one further page which is a security page (20), e.g. the passport's data page, bound immediately adjacent the cover page (10) and overlayable therewith, the security page (20) including a first face (22) which faces the cover page (10) when the cover and security pages (10, 20) are in their overlaid relationship, wherein: the security page (20) includes at least a first optical security feature, e.g. a hologram, (25) on its first face (22), the cover page (10) includes within its structure a window (12) of at least partially optically transparent material through which the first optical security feature (25) on the first face (22) of the security page (20) is visible or detectable when the cover and security pages (10, 20) are in their overlaid relationship, and at least one of the window (12) and / or the cover page (10) itself is / are provided with a, or a component of, a second optical security feature (35), the second optical security feature (35) being visible or detectable only once the cover and security pages (10, 20) have been brought into their overlaid relationship and is not so visible or detectable when the cover and security pages (10, 20) are in other than their overlaid relationship.

Description

[0001] DOCUMENT WITH COVERT SECURITY FEATURES AND METHOD OF MANUFACTURING IT

[0002] TECHNICAL FIELD

[0003] This invention relates to covert security features in documents, more particularly (though not exclusively) ID (identification) or security documents such as passports. The invention is especially applicable to such documents of a booklet type which comprise a plurality of pages. The invention also relates to such documents themselves, and to methods for their manufacture.

[0004] BACKGROUND OF THE INVENTION AND PRIOR ART

[0005] Passports and other booklet-type ID (identification) or other security documents are conventionally designed and manufactured so as to have a collection of various different security features incorporated into them. Some such security features are applied to the surfaces of various pages of the document / booklet, whereas other security features may be incorporated within the material of selected pages or even into the internal structure of parts of the document / booklet itself. However, with ever increasing instances and risks of counterfeiting and identity fraud, and ever increasing abilities of counterfeiters and fraudsters to copy or circumvent known security features, the demands placed on designers and manufacturers of passports and like documents / booklets by governments and security agencies / services to devise and introduce ever better and ever more secure and reliable security features therein are likewise ever increasing.

[0006] Booklet-type passports in particular are one type of security document which, because of its multi-page structure, is ripe for further improvement in this respect. Modern passports issued by most governments around the world generally comprise a booklet with a plurality of pages, including a data or security page - which is usually the first page in the passport and carries much of the holder’s personal data in printed, engraved or otherwise stored format - and a typically relatively stiff opaque front cover or outer binding page. The basic task of the cover is to protect the inner pages of the passport, and also to readily communicate the citizenship of the holder. In some cases, the cover is also a vehicle for containing RFID tags or electronics therewithin, i.e. as is the case in modern biometric passports.

[0007] In current passport structures and designs, because of hitherto limited permissible options for the materials and constructional techniques usable for passport covers / outer binding pages, up to now there have been very limited possibilities for integrating the design of the passport cover into the overall design concept of the passport itself. Indeed, in the art of passport manufacture there has up to now been no way to reliably and safely incorporate - without compromising security features inherent in such a cover / binding page or elsewhere in the passport - visual features into the cover / binding page’s construction that contribute to or tie in with an overall unique concept / theme of the passport, as modern passport aesthetics are increasingly being pressured to provide.

[0008] More recently, new developments in materials processing and passport assembly techniques have in principle brought about new possibilities for the design and manufacture of passports and similar booklet-style multi-page ID and other security documents. However, hitherto these have not found their way into practical applications that provide real-world improvements to passport aesthetics, especially of their covers / binding pages, whilst not compromising security features integrated into the pages and other parts of the passport itself. This means that passport covers / binding pages are not being used to their full technical and aesthetic potential, which also means that opportunities for enhanced security features inherent in such covers / binding pages are being missed too.

[0009] It is therefore a primary object of the present invention to address the above shortcomings and limitations of the known art and provide new possibilities for enhanced security features, especially coupled with enhanced aesthetics, of passports and similar booklet-style multipage ID and other security documents.

[0010] SUMMARY OF THE INVENTION

[0011] Accordingly, in a first aspect the present invention provides a document, especially an ID or security document, comprising a plurality of bound pages including a cover page and at least one further page which is a security page bound immediately adjacent the cover page and overlayable therewith, the security page including a first face which faces the cover page when the cover and security pages are in their overlaid relationship, wherein: the security page includes at least a first optical security feature on its first face, the cover page includes within its structure a window of at least partially optically transparent material through which the first optical security feature on the first face of the security page is visible or detectable when the cover and security pages are in their overlaid relationship, and at least one of the window and / or the cover page is / are provided with a, or a component of, a second optical security feature, the second optical security feature being visible or detectable only once the cover and security pages have been brought into their overlaid relationship and is not so visible or detectable when the cover and security pages are in other than their overlaid relationship.

[0012] In a second aspect the present invention provides a method of manufacturing a document, especially an ID or security document, comprising a plurality of pages including a cover page and at least one further page adjacent the cover page and overlayable therewith, the method comprising: providing a security page which is to constitute the said further page and which includes a first face, for facing the cover page when the cover and security pages are in their overlaid relationship, and having at least a first optical security feature thereon; providing a said cover page having preformed within its structure a window of at least partially optically transparent material through which the first optical security feature on the first face of the security page will be visible or detectable when the cover and security pages have been brought into their overlaid relationship, wherein at least one of the window and / or the cover page is / are provided with a, or a component of, a second optical security feature, the second optical security feature being such that it will be visible or detectable only once the cover and security pages have been brought into their overlaid relationship and will not be so visible or detectable when the cover and security pages are in other than their overlaid relationship; and binding the pages of the document together along a lateral edge thereof, with the security page being bound immediately adjacent the cover page and overlayable therewith when the pages of the document are closed together.

[0013] Embodiments of the invention in its various aspects may be applicable to documents of various kinds that take the form of a booklet comprising a plurality of bound pages. Embodiments of the invention are especially applicable to ID or security documents, in particular ID or security documents in bound multi-page booklet form. Passports in particular are an especially useful type of such document that embodiments of the invention are especially applicable to.

[0014] In many embodiments of the invention the cover page may be a front cover page of the document, and may thus if desired or appropriate carry or have applied or printed on a front face thereof one or more indicia or groups of indicia for indicating a general name and purpose of the document in question, e.g. in the case of a passport, the fact that it is a passport and the name of the country which has issued it.

[0015] In many embodiments of the invention the security page may be a data page which carries thereon or therein personal or other data, especially data relating uniquely to and identifying the owner or holder of the document, in printed, engraved or otherwise stored format, that data being carried (i) on a second face of the data page opposite the said first face thereof, or (ii) within its structure, or (iii) a combination of (i) and (ii).

[0016] In many practical such embodiments the personal or other data may be carried at least in part on the said second face of the data page, i.e. on the rear face of the data page opposite the front face thereof which is provided with the said first optical security feature and which faces the cover page when the cover and security pages assume their overlaid relationship.

[0017] In many practical embodiments of the invention, the first optical security feature may be provided on or applied to a portion or region only (i.e. less than the whole thereof) of the first face of the security page, that portion or region being located on the first face of the security page such that it is visible or detectable through the window in the cover page when the cover and security pages are in their overlaid relationship. That portion or region of the first face of the security page, on which the first optical security feature is provided or applied, and / or the first optical security feature itself, may be greater or smaller in size than the window in at least one lateral dimension. However, in some embodiments the dimensions of that portion or region, and / or the first optical security feature itself, may be such that the first optical security feature fits wholly within the boundaries or periphery of the window in the cover page when the cover and security pages are in their overlaid relationship.

[0018] In practical embodiments of the invention, the first optical security feature may be visible or detectable through the window in the cover page by means of light in any suitable region or wavelength / frequency band or range of the electromagnetic spectrum. Light in the visible region of the spectrum may be especially preferred. Alternatively, however, light which includes at least a portion that falls outside the visible region of the spectrum, e.g. infrared or ultraviolet light, may be used instead, if desired.

[0019] In many such embodiments, therefore, the window of the cover page may be of a material which is at least partially transparent to the light by which the first optical security feature is visible or detectable therethrough.

[0020] Likewise, in practical embodiments of the invention, the second optical security feature, which is visible or detectable only once the cover and security pages have been brought into their overlaid relationship and is not so visible or detectable when the cover and security pages are in other than their overlaid relationship, may independently be so visible or detectable by means of light in any suitable region or wavelength / frequency band or range of the electromagnetic spectrum. Light in the visible region of the spectrum may again be particularly preferred. However, as an alternative, for the purpose of providing enhanced security functions and capabilities, the light by which the second optical security feature is visible or detectable may instead fall, or may include at least a portion that falls, outside the visible region of the spectrum, e.g. in the infrared or ultraviolet regions of the spectrum.

[0021] In practical embodiments of the invention, the main body of the cover page, i.e. that / those part(s) of its structure other than the window therein, may broadly speaking be formed with a general structure and of materials that are the same as are already known for the cover or outer binding (or bounding) pages of known passports and like multi-page ID or security documents. The cover page may also incorporate within its structure a conventional RFID tag or other electronic component(s) for storing accessible personal or biometric data in a corresponding manner to known modern biometric passports and the like.

[0022] In embodiments of the invention the window in the cover page, through which the first optical security feature on the first face of the security page is visible or detectable when the cover and security pages are in their overlaid relationship, may be at least partially optically transparent by virtue of the window being either (i) formed of or filled with the optically transparent material, e.g. in the form of a sheet, film, web or patch thereof, which is bonded to the surrounding material of the cover page’s main body, especially to the portions of the cover page’s main body that surround or are adjacent the window therein, or (ii) entirely open and devoid of being composed of any material, i.e. the window is an empty region (e.g. a cutout, hole or void) formed in the main body of the cover page. Thus, in the latter case (ii) of the window being entirely open, the “transparent material” which, according to the above broad definitions of the invention, forms the window is to be understood as being atmospheric air or simply a void in space, which is indeed, or is tantamount to being, an “optically transparent” medium given that light can pass readily through it.

[0023] In embodiments of the invention the window in the cover page may be of any suitable shape, for example circular, elliptical, rectangular, square, polygonal, or indeed any regular or irregular or symmetrical or asymmetrical shape that may be desired for giving the document particular aesthetics to its front face or contributing to its overall design. The window may have linear sides, edges or walls with either substantially straight or gently (or evenly) curving arcuate or other curved sides, edges or walls, or it may have sides, edges or walls of any alternative non-linear or irregular or asymmetrical shape. In particular, in some embodiments the shape of the window in the cover page may be one feature of the document that is important for contributing to or providing a component of the second optical security feature, as is discussed further below.

[0024] In embodiments of the invention the first optical security feature may comprise any of a wide range of optical security features, and in particular it may be applied to or carried on or incorporated into the structure of the security page (especially the first face thereof) by any suitable means, e.g. various forms of printing, engraving, etching, embossing or some other recording technique such as an optical recording technique (e.g. using a laser or other light source).

[0025] In some such embodiments the first optical security feature may consist of or comprise an optically recreatable 2-dimensional or 3-dimensional recorded or encoded image, which image may be recreated or viewed or detected by any of optical transmission, reflection, refraction or diffraction, or any combination of any two more of the aforesaid optical phenomena.

[0026] More particularly, in some such embodiments the first optical security feature may comprise a hologram, e.g. one or more holographic (e.g. rainbow or achromatic) images recorded holographically within an optical material forming part of or being an additional layer (e.g. in the form of a film, foil, sheet, web or patch) applied to at least a portion of the first face of the security page, and which image(s) is / are recreatable under appropriate transmitted and / or reflected light. Such a hologram may thus be applied and bonded directly or indirectly to the surface of the first face of the security page or it may, at least in part, be incorporated into the internal structure of the security page.

[0027] Alternatively, in some other such embodiments the first optical security feature may comprise or be based on one or more images recorded in the form of an optical relief pattern, especially an optical micro- or nano-scale relief pattern applied to the surface of at least a portion of the first face of the security page. Suitable optical relief patterns may include those based on diffractive relief, or alternatively non-diffractive, e.g. refractive, relief, which image(s) may again be recreatable under appropriate transmitted and / or reflected light.

[0028] Further alternatively, in some yet other such embodiments the first optical security feature may comprise or be based on one or more optically visible / observable or detectable features formed by various types of surface printing or embossing or stamping or nano-imprinting lithography, e.g. visible surface printing using various colours in the visible region of the electromagnetic spectrum, IR-visible (infra-red-visible) printing, or UV-visible (ultraviolet- visible) printing, as well as possibly other such examples thereof.

[0029] For practising various embodiments of the invention, suitable methods, techniques and apparatuses that may be used for forming or recording or applying any of above types or examples of the first optical security feature to the first face of the security page will be well- known in the art and will be widely available and well understood by persons skilled in the art.

[0030] In accordance with the present invention the second optical security feature is visible or detectable only once the cover and security pages have been brought into their overlaid relationship, and is not so visible or detectable when the cover and security pages are in other than their overlaid relationship, e.g. when the passport or other document is open, with its cover and security pages opened apart and not overlaying one another. To achieve this, at least one of the window and / or the cover page is / are provided with a, or a component of, the second optical security feature.

[0031] In principle, in embodiments of the invention the second optical security feature may comprise any of a wide range of optical security features, which may - independently of the type or identity of the first security feature - be any of the same types and examples of optical security features as defined and discussed above in the context of the first optical security feature. Thus, such general possibilities for the second optical security feature are reiterable here and incorporated here again by reference to that disclosure earlier hereinabove.

[0032] In one species of such embodiments the second optical security feature may be formed so as to be visible or detectable by a physical combining together in an overlaid relationship of the cover page itself and the first optical security feature on the first face of the security page. Furthermore, the second optical security feature may only become so visible or detectable upon that overlaid relationship of the cover and security pages being adopted, and it may remain non-visible or non-detectable whilst those two pages are not in that overlaid relationship or have not yet been brought into that overlaid relationship. For this purpose, in such embodiments, at least one of the window and / or the cover page - preferably the cover page itself, and more preferably a front face of the cover page - may be provided with a first component of the second optical security feature, and a second (or at least one other) component of the second optical security feature may be provided by the first optical security feature and visible or detectable through the window in the cover page when the cover and security pages have been brought into their overlaid relationship, whereby the complete second optical security feature is created and visible or detectable by (and only upon) the combining together of those first and second (or other) components once the cover and security pages have been brought into their overlaid relationship.

[0033] For example, the first and second components of the second optical security feature - which are provided, respectively, on (in many such embodiments) the front face of the cover page and the front face of the security page - may each independently of the other be selected from a portion or component of, which is less or smaller than the whole of, a printed, engraved, etched, embossed or optically recorded image, design, picture, logo, indicia, emblem, pattern, artistic work, combination of one or more alphanumeric characters, or other object (especially for example one that is suitably unique and / or complex in its composition) that can be designed to be unique to the document in question, so as to serve its unique security, ID, authentication or other like purpose. At least one of the first and second components of the second optical security feature may be a hologram or holographically recorded image, design, picture, logo, indicia, emblem, pattern, artistic work, combination of one or more alphanumeric characters, or other suitably unique or complex object. Thus, it is only upon both the first and second components of the second optical security feature coming together and being visible / detectable in their totality upon the cover and security pages being brought into their overlaid relationship, that the whole of the image, design, logo or indicia forming the second optical security feature is created (or recreated) and recognisable as such.

[0034] However, in another species of such embodiments the second optical security feature may be formed so as to be visible or detectable by an optically functional combining together in a physically overlaid relationship of the window in the cover page and the first optical security feature on the first face of the security page. Again, therefore, the second optical security feature may only become so visible or detectable upon that optically functional overlaid relationship of the cover and security pages being adopted, and it may remain non-visible or non-detectable whilst those two pages are not in that optically functional overlaid relationship or have not yet been brought into that optically functional overlaid relationship. For this purpose, in such embodiments, the window in the cover page may be formed of an at least partially optically transparent yet optically active material which has incorporated or recorded therein or applied to a surface thereof a first optically functional component of the second optical security feature, and a second (or at least one other) optically functional component of the second optical security feature may be provided by (or constitutes or is formed as a part or component of) the first optical security feature on the front face of the security page and visible or detectable through the window in the cover page when the cover and security pages have been brought into their overlaid relationship, whereby the complete second optical security feature may be created and visible or detectable by (and only upon) the combining together of that / those first and second (or other) components once the cover and security pages have been brought into their overlaid relationship.

[0035] Thus, in such embodiments the first and second (or at least one other) optically functional components of the second optical security feature may be constituted or provided by different respective layers of the document in the manner of a plural-layer optical security feature whose respective layers each comprise a respective component of the second optical security feature and which plural layers act or function optically together to form or create or recreate or render visible or detectable the second optical functional security feature only when or once the cover and security pages have been brought into their overlaid relationship, and preferably not before, and the second optical security feature disappears from view or visibility or detectability when the cover and security pages are mutually displaced from their overlaid relationship.

[0036] Thus, in simple practical terms, in such embodiments where a first optically functional component of the second optical security feature is provided by the window in the cover page and a second (or at least one other) optically functional component of the second optical security feature is provided by (or constitutes or is formed as a part or component of) the first optical security feature on the front face of the security page, the window in the cover page may act as a “reader” of one or more security elements hidden in or on the security page, especially in or on the first face thereof, either in the first optical security feature itself or in some other region or portion of that first face of the security page or in some other or additional security feature provided on that first face.

[0037] As one example, the first and second optically functional components of the second optical security feature - which are provided, respectively, in or on the window in the cover page and the front face of the security page (by virtue of constituting or forming a part or component of the first optical security feature on the front face of the security page) - may each independently of the other be selected from an optical grating or relief-type optically functional element or feature which acts by refraction or diffraction (or a combination thereof) so as to form or produce, in combination with the other one thereof, the second optical security feature by a moire effect, e.g. a holographic moire effect. Such a moire effect may be designed to produce as the second optical security feature any suitable form of image, design, picture, logo, indicia, emblem, pattern, artistic work, combination of one or more alphanumeric characters, or other object (especially for example one that is suitably unique and / or complex in its composition) that can be designed to be unique to the document in question, so as to serve its unique security, ID, authentication or other like purpose. Moire optical effects and how they may be created to produce a wide range of visual or detectable images or static or moving optical effect are well-known in the art.

[0038] As another example, the first and second optically functional components of the second optical security feature - which are provided, respectively, in or on the window in the cover page and the front face of the security page (by virtue of constituting or forming a part or component of the first optical security feature on the front face of the security page) - may each independently of the other be selected from an optical polarizing element, e.g. an optically polarizing filter element or layer (e.g. film), which acts to polarize light passing therethrough in a respective specific axis, direction, shape or pattern so as to form or produce, in combination with the other one thereof, the second optical security feature by a combined optical polarization effect. Such optical polarizing elements may for example take the form of transparent polarization films, which may even be locally variable in terms of their transparency or type of polarization effect or function, so that particular combined polarization effects (e.g. possibly complex ones) may be produced. As with moire effects, such combined optical polarization effects may also be designed to produce as the second optical security feature any suitable form of image, design, picture, logo, indicia, emblem, pattern, artistic work, combination of one or more alphanumeric characters, or other object (especially for example one that is suitably unique and / or complex in its composition) that can be designed to be unique to the document in question, so as to serve its unique security, ID, authentication or other like purpose. Specific practical examples of optical polarizing filters or layer / film elements (e.g. based on liquid crystals or special inks, as just two examples) are well-known in the art and readily commercially available.

[0039] As yet another example, the first and second optically functional components of the second optical security feature - which are provided, respectively, in or on the window in the cover page and the front face of the security page (by virtue of constituting or forming a part or component of the first optical security feature on the front face of the security page) - may each independently of the other be selected from an optical element with selectively locally varying transparency and / or selectively locally varying diffraction properties, which acts to create, in combination with the locally varying transparency and / or locally varying diffraction properties of the other one thereof, certain specific optical effects characteristic of such combined locally varying transparency and / or diffraction properties, so as to form or produce, when the two optically functional components are applied or combined together, the second optical security feature. Such optical elements with selectively locally varying transparency and / or selectively locally varying diffraction properties may for example take the form of an optical element with locally varying transparency of a diffractive surface (e.g. a surface with diffractive surface relief) created by a specific diffractive surface relief profile in combination with specific locally varying surface over-printing (e.g. with a suitable ink) or selective metallization (e.g. by a coating layer of a suitable metal, such as Ni, Cu, Al, Ag, Cr among possibly other metals) of that surface, e.g. portion(s) of the surface is / are partially demetallized (or non-metallized) or is / are specially metallized under a certain angle (i.e. angle of the relief features) or with some other specific locally varying metallization pattern or arrangement, so that the metallized surface has locally varying transparency properties. As with moire and combined polarization effects, such combined locally varying transparency and / or diffraction property effects may also be designed to produce as the second optical security feature any suitable form of image, design, picture, logo, indicia, emblem, pattern, artistic work, combination of one or more alphanumeric characters, or other object (especially for example one that is suitably unique and / or complex in its composition) that can be designed to be unique to the document in question, so as to serve its unique security, ID, authentication or other like purpose. Specific practical examples of optical element which exhibit combined locally varying transparency and / or diffraction properties are well-known in the art and readily commercially available.

[0040] Of course, other examples of second optical security features of other types, which are (re)creatable by a combining together of the first and second optically functional components thereof in / on the window of the cover page and the front face of the security page may be possible in yet other embodiments.

[0041] Thus, in such embodiments relying on moire, combined optical polarization or combined locally varying transparency and / or diffraction property effects, or even other optically functional effects, to form or produce the second optical security feature, it is again only upon the cover and security pages being brought into their overlaid relationship that the image, design, picture, logo, indicia, emblem, pattern, artistic work, combination of one or more alphanumeric characters, or other suitably unique or complex object, forming the second optical security feature is created (or recreated) and becomes visible / detectable and recognisable as such.

[0042] In some embodiments of the invention the first face of the security page may even include or carry or have applied thereto / thereon one or more additional or tertiary optical security features, independent of the first optical security feature itself, or of a second (or at least one other) optically functional component of the second optical security feature which is provided by (or constitutes or is formed as a part or component of) the first optical security feature on the front face of the security page, which additional or tertiary optical security feature may or may not be visible / detectable though the window in the cover page when the cover and security pages are or have been brought into their overlaid relationship and thus which may or may not further contribute to the overall security functions of the first and second optical security features, or may constitute an independent additional (or tertiary) security feature in its own right. Practical examples of such additional or tertiary security features may include any of those defined above for the first optical security feature.

[0043] In manufacturing passports or other ID or security documents in accordance with practical embodiments of the invention, any suitable techniques, materials and methods may be used as are already well-known in the art for constructing the main multi-page bound structure of the document itself. In particular, the manner in which the plurality of pages, including the cover page and the at least one further page which is a security page (e.g. the data page), optionally together with one or more further pages (e.g. visa pages), are bound together - especially along one lateral edge - to form a booklet-type document may be according to conventional techniques in the art of passport and like ID / security documents manufacturing.

[0044] Thus, many embodiments of the present invention may provide for the introduction of new and improved ID or security documents such as (and especially) passports, and like bookletstyle plural-paged documents, which may be designed to have a markedly improved range or security and aesthetic properties. These may be derived at least in part from recent developments in materials processing and passport (or like documents) assembly techniques, as well as new approaches to designing passports and like documents which have improved aesthetic as well as security features. For instance, by use of embodiments of the invention a passport (or like document) cover may host and visualize a range of ideas unique to or indicative of a general concept inherent in the passport (or like document). Such a cover may carry any printed (or otherwise applied) pattern(s), e.g. from trivial solid colours to sophisticated security printed (or otherwise applied) elements and may also have integrated therein one or more other optical or electronic security features, and even RFID tag(s). Thus, all the conventional physical and mechanical protective functions required from a passport (or like document) cover are preserved. However, by use of embodiments of the present invention it is now possible for architects and designers of passports (and like documents) to introduce a range of other and more advanced security features thereto which may confer on such documents enhanced types and degrees of optical-based security features / parameters, especially via their integration into the overall design and security parameters of the document (e.g. passport). Thus, in the case of passports in particular, the aesthetics and overall enhanced collection of integrated security features of booklet-type such documents may help border personnel and security officials to better authenticate passports and identify their holders with enhanced levels of security yet by no more complicated or time-consuming procedures, and even at the same time encourage passport holders to deepen their citizenship awareness.

[0045] Within the scope of this specification it is envisaged that the various aspects, embodiments, examples, features and alternatives, and in particular the individual constructional, configurational or operational features thereof, set out in the preceding paragraphs, in the claims and / or in the following description and accompanying drawings, may be taken independently or in any combination of any number of same. For example, individual features described in connection with one particular embodiment, or described singly or in combination with another feature in any one or more embodiments, are applicable on their own or in combination with one or more other features to all embodiments and may be found and used in combination with any other feature in any given embodiment, unless expressly stated otherwise or such features are incompatible.

[0046] BRIEF DESCRIPTION OF THE DRAWINGS

[0047] One or more embodiments of the invention will now be described in detail, by way of example only, with reference to the accompanying drawings, in which:

[0048] FIGURE 1 is a front face-on view of one example of a booklet-type passport document according to an embodiment of the present invention, showing the passport with its various pages closed up and the front cover page overlying the second data page, in which closed condition the special unique second security feature formed by the combined overlaid front cover and first face of the data page is visible; and

[0049] FIGURE 2 is a perspective view inside the passport of FIG. 1 , with its pages opened up and looking in between the front cover page and front face of the second data page, in which open condition the normally transparent window in the front cover page and the first optical security feature on the first face of the data page are visible, but the second security feature is not yet visible.

[0050] DETAILED DESCRIPTION OF EMBODIMENTS

[0051] Referring to FIGS. 1 and 2, the passport 1 is in the form of a booklet with a plurality of bound pages, hingedly bound in a convention manner along a left-hand lateral edge 3. The passport includes a relative stiff front outer cover page 10, which extends around the passport to form also its rear cover (not shown). As well as providing a site for a printed or embossed indicator of the fact that the passport is such a document, the front cover page 10 also has incorporated into its structure a RFID tag or chip 9, which stores electronically-readable personal data of the passport 1’s holder, so that the passport can constitute a so-called “biometric” passport 1. The first inner page of the passport 1 is a security page 20, which in most practical examples is the passport’s main data page 20 (e.g. of polycarbonate material or layered therewith) carrying in either printed or coded format and typically on the second, rearward-facing face of the data page 20 (i.e. that rearward-facing face not visible in FIG. 2) the personal data of the passport’s holder.

[0052] Carried on the first, i.e. forward-facing, face 22 of the data page 20 is a security hologram 25, which forms a main, first, optical security feature. Such a hologram 25 comprises any suitable ornate or complex security image, such as a 2-dimensional or 3-dimensional recorded or encoded image which is viewable under reflected visible light, and is applied by any appropriate known technique to the surface of the first face 22 of the data page 20. By way of example, the hologram 25 may comprise a holographic (e.g. rainbow or achromatic) image recorded holographically within an optical material forming part of or applied as an additional layer (e.g. in the form of a film, foil, sheet, web or patch) to a portion of the first face 22 of the data page 20. Of course, other known types of hologram and other methods for format and application to the first face 22 of the data page 20 are possible.

[0053] The cover page 10 contains an elliptical window 12 of what for most practical purposes and to a casual viewer - especially when the passport pages are open (as they are in FIG. 2) and the pages are being inspected individually - is an optically substantially transparent material, e.g. an optically substantially transparent polymer material, of which the art contains many suitable practical examples. The main first optical security hologram 25 is visible through the window 12 in the cover page 10, so that the hologram 25 itself provides an authentication / security function, by virtue of its ability to be resistant to copying or fraudulent reproduction and whose verisimilitude can be checked by any suitable known means appropriate for that hologram.

[0054] However, formed in a “hidden” manner within (i) the material of the window 12 and (ii) the hologram 25 itself are first and second components of a second optical security feature 35, which in this illustrated example is in the form of indicia being the letters “IQ”. These “hidden” letters 35 are formed in this example by a moire effect, produced by an overlaying of a first, optical micro- or nano-scale grating component feature formed within the layer of material forming the window 12 in the cover page 10, with a second, optical micro- or nano-scale relief component feature formed within the hologram 25 on the first face 22 of the data page 20. These first and second micro- or nano-scale grating and relief component features are designed, constructed and formed in their respective substrate materials by well-known techniques and methods for the construction of moire type holographic images. The first and second micro- or nano-scale grating and relief component features are thus to most practical intents and purposes - and to the casual viewer - invisible under conditions where the passport pages are open and the pages are being inspected individually (as they are in FIG. 2), but they combine together to create and render visible the “hidden” indicia 35 constituting the second optical security feature only once the cover and data pages 10, 20 are brought into their overlaid relationship once the passport pages have been closed, as they are in FIG. 1.

[0055] Thus, in this manner, by appropriate design of the “hidden” moire features (which constitute the second optical security feature 35) which form each of the first and second optical micro- or nano-scale grating and relief component features formed, respectively, within the layer of material forming the window 12 in the cover page 10 and within the hologram 25 on the first face 22 of the data page 20, an enhanced degree of security and authentication reliability can be achieved.

[0056] Of course, other types of “hidden” second optical security features (e.g. 35) formed by the combining or bringing together of the first and second component features formed within the layer of material forming the window 12 in the cover page 10 and within the hologram 25 on the first face 22 of the data page 20 may be possible in other example embodiments, by appropriate choice and design of the optical functions of the first and second component features in question, as will be well within the purview and practical knowledge and skill of persons skilled in the present art. For example, similar “hidden” second optical security features (e.g. 35) may be formed by the first and second component features thereof being either (a) respective optical polarizing elements, especially optically polarizing filter elements, layers or films, which act to polarize light passing therethrough in respective specific axes, directions, shapes or patterns so as to form or produce, in combination with each other, the second optical security feature by a combined optical polarization effect, or (b) respective optical elements with respective selectively locally varying transparency and / or selectively locally varying diffraction properties, which act to create, in combination with the locally varying transparency and / or locally varying diffraction properties of each other, certain specific optical effects characteristic of such combined locally varying transparency and / or diffraction properties, so as to form or produce, when the two optically functional components are applied or combined together, the second optical security feature. Such alternative first and second component features of types (a) and (b) for forming such alternative “hidden” second optical security features, as well as some specific practical examples thereof, are described in further detail hereinabove.

[0057] Throughout the description and claims of this specification, the words “comprise” and “contain” and linguistic variations of those words, for example “comprising” and “comprises”, mean “including but not limited to”, and are not intended to (and do not) exclude other moieties, additives, components, elements, integers or steps.

[0058] Throughout the description and claims of this specification, the singular encompasses the plural unless expressly stated otherwise or the context otherwise requires. In particular, where the indefinite article is used, the specification is to be understood as contemplating plurality as well as singularity, unless expressly stated otherwise or the context requires otherwise.

[0059] Throughout the description and claims of this specification, features, components, elements, integers, characteristics, properties, compounds, chemical moieties or groups described in conjunction with a particular aspect, embodiment or example of the invention are to be understood to be applicable to any other aspect, embodiment or example described herein unless incompatible therewith or expressly stated otherwise.

[0060] Furthermore, it is expressly envisaged in this disclosure of the present invention that the various aspects, embodiments, examples, features and alternatives, and in particular the individual constructional, configurational or operational features thereof, set out in the preceding paragraphs, in the claims and / or in the following description and accompanying drawings, may be taken independently or in any combination of any number of same. For example, individual features described in connection with one particular embodiment, or described singly or in combination with another feature in any one or more embodiments, are applicable on their own or in combination with one or more other features to all embodiments and may be found and used in combination with any other feature in any given embodiment, unless expressly stated otherwise or such features are incompatible.

Claims

CLAIMS1. A document, optionally an ID or security document, comprising a plurality of bound pages including a cover page and at least one further page which is a security page bound immediately adjacent the cover page and overlayable therewith, the security page including a first face which faces the cover page when the cover and security pages are in their overlaid relationship, wherein: the security page includes at least a first optical security feature on its first face, the cover page includes within its structure a window of at least partially optically transparent material through which the first optical security feature on the first face of the security page is visible or detectable when the cover and security pages are in their overlaid relationship, and at least one of the window and / or the cover page is / are provided with a, or a component of, a second optical security feature, the second optical security feature being visible or detectable only once the cover and security pages have been brought into their overlaid relationship and is not so visible or detectable when the cover and security pages are in other than their overlaid relationship.

2. A document according to claim 1 , which is a passport.

3. A document according to claim 1 or claim 2, wherein the cover page is a front cover page of the document, and carries or has applied or printed on a front face thereof one or more indicia or groups of indicia for indicating a general name and purpose of the document in question, and optionally in the case of a passport the fact that it is a passport and the name of the country which has issued it.

4. A document according to any one of claims 1 to 3, wherein the security page is a data page which carries thereon or therein personal or other data, optionally data relating uniquely to and identifying the owner or holder of the document, in printed, engraved or otherwise stored format, that data being carried (i) on a second face of the data page opposite the said first face thereof, or (ii) within its structure, or (iii) a combination of (i) and (ii).

5. A document according to claim 4, wherein the personal or other data is carried at least in part on the said second face of the data page, i.e. on the rear face of the data page opposite the front face thereof which is provided with the said first optical security feature and which faces the cover page when the cover and security pages assume their overlaid relationship.

6. A document according to any preceding claim, wherein the first optical security feature is provided on or applied to a portion or region only (i.e. less than the whole thereof) of the first face of the security page, that portion or region being located on the first face of the security page such that it is visible or detectable through the window in the cover page when the cover and security pages are in their overlaid relationship, and wherein that portion or region of the first face of the security page, on which the first optical security feature is provided or applied, and / or the first optical security feature itself, is greater or smaller in size than the window in at least one lateral dimension.

7. A document according to claim 6, wherein the dimensions of the said portion or region of the first face of the security page, and / or the first optical security feature itself, are such that the first optical security feature fits wholly within the boundaries or periphery of the window in the cover page when the cover and security pages are in their overlaid relationship.

8. A document according to any preceding claim, wherein the first optical security feature is visible or detectable through the window in the cover page by means of light in the visible region of the electromagnetic spectrum, and the window of the cover page is of a material which is at least partially transparent to visible light.

9. A document according to any preceding claim, wherein the second optical security feature, which is visible or detectable only once the cover and security pages have been brought into their overlaid relationship and is not so visible or detectable when the cover and security pages are in other than their overlaid relationship, is so visible or detectable by means of light in the visible region of the electromagnetic spectrum.

10. A document according to any preceding claim, wherein the window in the cover page, through which the first optical security feature on the first face of the security page is visible or detectable when the cover and security pages are in their overlaid relationship, is at least partially optically transparent by virtue of the window being either (i) formed of or filled with the optically transparent material, optionally in the form of a sheet, film, web or patch thereof, which is bonded to the surrounding material of the cover page’s main body, or (ii) entirely open and devoid of being composed of any material, i.e. the window is an empty region formed in the main body of the cover page.

11. A document according to any preceding claim, wherein the first optical security feature consists of or comprises an optically recreatable 2-dimensional or 3-dimensionalrecorded or encoded image, which image is recreatable or viewable or detectable by any of optical transmission, reflection, refraction or diffraction, or any combination of any two more of the aforesaid optical phenomena.

12. A document according to claim 11 , wherein the first optical security feature comprises a hologram, wherein the hologram one or more holographic images recorded holographically within an optical material forming part of or being an additional layer applied to at least a portion of the first face of the security page, and which image(s) is / are recreatable under appropriate transmitted and / or reflected light.

13. A document according to claim 11 or claim 12, wherein the first optical security feature comprises or is based on one or more images recorded in the form of an optical relief pattern applied to the surface of at least a portion of the first face of the security page.

14. A document according to any one of claims 11 to 13, wherein the first optical security feature comprises or is based on one or more optically visible / observable or detectable features formed by a technique selected from surface printing, embossing, stamping or nanoimprinting lithography.

15. A document according to any one of claims 1 to 14, wherein the second optical security feature is formed so as to be visible or detectable by a physical combining together in an overlaid relationship of the cover page itself and the first optical security feature on the first face of the security page, optionally further wherein the second optical security feature only becomes so visible or detectable upon that overlaid relationship of the cover and security pages being adopted, and it remains non-visible or non-detectable whilst those two pages are not in that overlaid relationship or have not yet been brought into that overlaid relationship.

16. A document according to claim 15, wherein at least one of the window and / or the cover page, optionally the cover page itself and further optionally a front face of the cover page, is provided with a first component of the second optical security feature, and a second or at least one other component of the second optical security feature is provided by the first optical security feature and visible or detectable through the window in the cover page when the cover and security pages have been brought into their overlaid relationship, whereby the complete second optical security feature is created and visible or detectable by, and only upon, the combining together of those first and second (or other) components once the cover and security pages have been brought into their overlaid relationship.

17. A document according to claim 16, wherein the first and second components of the second optical security feature are provided, respectively, on the front face of the cover page and the front face of the security page, and are each independently of the other selected from a portion or component of, which is less or smaller than the whole of, a printed, engraved, etched, embossed or optically recorded image, design, picture, logo, indicia, emblem, pattern, artistic work, combination of one or more alphanumeric characters, or other object that is designed to be unique to the document in question so as to serve a unique security, ID or authentication purpose therefor.

18. A document according to claim 17, wherein at least one of the first and second components of the second optical security feature is a hologram or holographically recorded image, design, picture, logo, indicia, emblem, pattern, artistic work, combination of one or more alphanumeric characters, or other suitably unique or complex object, whereby it is only upon both the first and second components of the second optical security feature coming together and being visible / detectable in their totality upon the cover and security pages being brought into their overlaid relationship, that the whole of the image, design, logo or indicia forming the second optical security feature is created (or recreated) and recognisable as such.

19. A document according to any one of claims 1 to 14, wherein the second optical security feature is formed so as to be visible or detectable by an optically functional combining together in a physically overlaid relationship of the window in the cover page and the first optical security feature on the first face of the security page, whereby the second optical security feature only becomes so visible or detectable upon that optically functional overlaid relationship of the cover and security pages being adopted, and it remains non- visible or non-detectable whilst those two pages are not in that optically functional overlaid relationship or have not yet been brought into that optically functional overlaid relationship.

20. A document according to claim 19, wherein the window in the cover page is formed of an at least partially optically transparent yet optically active material which has incorporated or recorded therein or applied to a surface thereof a first optically functional component of the second optical security feature, and a second or at least one other optically functional component of the second optical security feature is provided by, or constitutes or is formed as a part or component of, the first optical security feature on the front face of the security page and visible or detectable through the window in the cover page when the cover and security pages have been brought into their overlaid relationship, whereby the completesecond optical security feature is creatable and visible or detectable by, and only upon, the combining together of that / those first and second (or at least one other) components once the cover and security pages have been brought into their overlaid relationship, optionally wherein the first and second (or at least one other) optically functional components of the second optical security feature are constituted or provided by different respective layers of the document in the manner of a plural-layer optical security feature whose respective layers each comprise a respective component of the second optical security feature and which plural layers act or function optically together to form or create or recreate or render visible or detectable the second optical functional security feature only when or once the cover and security pages have been brought into their overlaid relationship, and preferably not before, and further preferably the second optical security feature disappears from view or visibility or detectability when the cover and security pages are mutually displaced from their overlaid relationship.

21. A document according to claim 20, wherein the first and second optically functional components of the second optical security feature are provided, respectively, in or on the window in the cover page and the front face of the security page (by virtue of constituting or forming a part or component of the first optical security feature on the front face of the security page), and are each independently of the other selected from:(i) an optical grating or relief-type optically functional element or feature which acts by refraction or diffraction, or a combination thereof, to form or produce, in combination with the other one thereof, the second optical security feature by a moire effect, optionally a holographic moire effect; or(ii) an optical polarizing element, optionally an optically polarizing filter element or layer, which acts to polarize light passing therethrough in a respective specific axis, direction, shape or pattern so as to form or produce, in combination with the other one thereof, the second optical security feature by a combined optical polarization effect; or(iii) an optical element with selectively locally varying transparency and / or selectively locally varying diffraction properties, which acts to create, in combination with the locally varying transparency and / or locally varying diffraction properties of the other one thereof, certain specific optical effects characteristic of such combined locally varying transparency and / or diffraction properties, so as to form or produce, when the two optically functional components are applied or combined together, the second optical security feature.

22. A document according to claim 21 , wherein the (i) moire effect or (ii) combined optical polarization effect or (iii) combined locally varying transparency and / or diffraction property effects, as the case may be, is designed to produce as the second optical security featurean image, design, picture, logo, indicia, emblem, pattern, artistic work, combination of one or more alphanumeric characters, or other object that is designed to be unique to the document in question so as to serve a unique security, ID or authentication purpose therefor.

23. A document according to any preceding claim, wherein the first face of the security page includes or carries or has applied thereto / thereon one or more tertiary optical security features, independent of the first optical security feature itself, or of a second (or at least one other) optically functional component of the second optical security feature which is provided by (or constitutes or is formed as a part or component of) the first optical security feature on the front face of the security page, which additional or tertiary optical security feature is or is not visible / detectable though the window in the cover page when the cover and security pages are or have been brought into their overlaid relationship.

24. A method of manufacturing a document, optionally an ID or security document, comprising a plurality of pages including a cover page and at least one further page adjacent the cover page and overlayable therewith, the method comprising: providing a security page which is to constitute the said further page and which includes a first face, for facing the cover page when the cover and security pages are in their overlaid relationship, and having at least a first optical security feature thereon; providing a said cover page having preformed within its structure a window of at least partially optically transparent material through which the first optical security feature on the first face of the security page will be visible or detectable when the cover and security pages have been brought into their overlaid relationship, wherein at least one of the window and / or the cover page is / are provided with a, or a component of, a second optical security feature, the second optical security feature being such that it will be visible or detectable only once the cover and security pages have been brought into their overlaid relationship and will not be so visible or detectable when the cover and security pages are in other than their overlaid relationship; and binding the pages of the document together along a lateral edge thereof, with the security page being bound immediately adjacent the cover page and overlayable therewith when the pages of the document are closed together.

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