CA2247974C - A security element for documents and a method for its fabrication - Google Patents
A security element for documents and a method for its fabrication Download PDFInfo
- Publication number
- CA2247974C CA2247974C CA002247974A CA2247974A CA2247974C CA 2247974 C CA2247974 C CA 2247974C CA 002247974 A CA002247974 A CA 002247974A CA 2247974 A CA2247974 A CA 2247974A CA 2247974 C CA2247974 C CA 2247974C
- Authority
- CA
- Canada
- Prior art keywords
- volume hologram
- security element
- local areas
- substrate
- document
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
- 238000000034 method Methods 0.000 title claims description 16
- 238000004519 manufacturing process Methods 0.000 title description 4
- 230000000694 effects Effects 0.000 claims abstract description 12
- 239000000758 substrate Substances 0.000 claims abstract description 10
- 230000003287 optical effect Effects 0.000 claims abstract description 9
- 230000008961 swelling Effects 0.000 claims description 5
- 230000000699 topical effect Effects 0.000 description 5
- 239000000463 material Substances 0.000 description 3
- 230000001427 coherent effect Effects 0.000 description 2
- 230000006978 adaptation Effects 0.000 description 1
- 239000003086 colorant Substances 0.000 description 1
- 239000006185 dispersion Substances 0.000 description 1
- 238000005286 illumination Methods 0.000 description 1
- 238000001228 spectrum Methods 0.000 description 1
Classifications
-
- G—PHYSICS
- G07—CHECKING-DEVICES
- G07D—HANDLING OF COINS OR VALUABLE PAPERS, e.g. TESTING, SORTING BY DENOMINATIONS, COUNTING, DISPENSING, CHANGING OR DEPOSITING
- G07D7/00—Testing specially adapted to determine the identity or genuineness of valuable papers or for segregating those which are unacceptable, e.g. banknotes that are alien to a currency
- G07D7/003—Testing specially adapted to determine the identity or genuineness of valuable papers or for segregating those which are unacceptable, e.g. banknotes that are alien to a currency using security elements
- G07D7/0032—Testing specially adapted to determine the identity or genuineness of valuable papers or for segregating those which are unacceptable, e.g. banknotes that are alien to a currency using security elements using holograms
-
- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03H—HOLOGRAPHIC PROCESSES OR APPARATUS
- G03H1/00—Holographic processes or apparatus using light, infrared or ultraviolet waves for obtaining holograms or for obtaining an image from them; Details peculiar thereto
- G03H1/02—Details of features involved during the holographic process; Replication of holograms without interference recording
- G03H1/024—Hologram nature or properties
- G03H1/0244—Surface relief holograms
-
- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03H—HOLOGRAPHIC PROCESSES OR APPARATUS
- G03H1/00—Holographic processes or apparatus using light, infrared or ultraviolet waves for obtaining holograms or for obtaining an image from them; Details peculiar thereto
- G03H1/02—Details of features involved during the holographic process; Replication of holograms without interference recording
- G03H1/024—Hologram nature or properties
- G03H1/0248—Volume holograms
-
- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03H—HOLOGRAPHIC PROCESSES OR APPARATUS
- G03H1/00—Holographic processes or apparatus using light, infrared or ultraviolet waves for obtaining holograms or for obtaining an image from them; Details peculiar thereto
- G03H1/0005—Adaptation of holography to specific applications
- G03H1/0011—Adaptation of holography to specific applications for security or authentication
- G03H2001/0027—Being copy-protected against fraudulent replication, e.g. by layering a filter rejecting laser lines
-
- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03H—HOLOGRAPHIC PROCESSES OR APPARATUS
- G03H1/00—Holographic processes or apparatus using light, infrared or ultraviolet waves for obtaining holograms or for obtaining an image from them; Details peculiar thereto
- G03H1/04—Processes or apparatus for producing holograms
- G03H1/18—Particular processing of hologram record carriers, e.g. for obtaining blazed holograms
- G03H2001/186—Swelling or shrinking the holographic record or compensation thereof, e.g. for controlling the reconstructed wavelength
-
- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03H—HOLOGRAPHIC PROCESSES OR APPARATUS
- G03H1/00—Holographic processes or apparatus using light, infrared or ultraviolet waves for obtaining holograms or for obtaining an image from them; Details peculiar thereto
- G03H1/04—Processes or apparatus for producing holograms
- G03H1/20—Copying holograms by holographic, i.e. optical means
- G03H2001/207—Copying holograms by holographic, i.e. optical means with modification of the nature of the hologram, e.g. changing from volume to surface relief or from reflection to transmission
-
- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03H—HOLOGRAPHIC PROCESSES OR APPARATUS
- G03H1/00—Holographic processes or apparatus using light, infrared or ultraviolet waves for obtaining holograms or for obtaining an image from them; Details peculiar thereto
- G03H1/22—Processes or apparatus for obtaining an optical image from holograms
- G03H1/2249—Holobject properties
- G03H2001/2263—Multicoloured holobject
Landscapes
- Engineering & Computer Science (AREA)
- Computer Security & Cryptography (AREA)
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Holo Graphy (AREA)
- Credit Cards Or The Like (AREA)
- Compositions Of Oxide Ceramics (AREA)
- Medicines Containing Antibodies Or Antigens For Use As Internal Diagnostic Agents (AREA)
- Adornments (AREA)
- Forging (AREA)
- Feeding, Discharge, Calcimining, Fusing, And Gas-Generation Devices (AREA)
Abstract
A document consists of a substrate (1) and a security element which comprises an optical grating. In order to enhance the copying security, the optical grating is a volume hologram (2) into which a kinetic effect has been introduced (Fig. 2).
Description
A Security Element For Documents and A Method For Its Fabrication Field of the Invention The invention relates to a document with a substrate and a security element which comprises an optical grating and to a security element for such a document.
The invention further relates to a method for the fabrication of such a document or security element.
Background of the Invention With documents of the most varied type, for example with bank notes, securities or similar documents, a security element is often required which is intended to provide protection against copying. Security elements of this type which comprise an optical grating are well known in the art. In the solutions previously known, optical gratings are used which are designed as surface reliefs. However, the copy protection obtained in this way is not sufficient in all cases.
It is therefore the object of the invention to improve the copy protection in documents with a security element.
Summary of the Invention The present invention relates to an optical grating comprising a volume hologram into which a kinetic effect is introduced. In this way, a substantially greater copy protection can be achieved.
In the fabrication of a volume hologram, a film or another grain-free, translucent, photosensitive medium is irradiated with coherent light, in particular with laser light.
Due to interference in the film material, Bragg network planes are created which embody the information written in the hologram.
(Dne advantageous embodiment is characterised in that the volume hologram has been fabricated with two or more different wavelengths. In this way, a controlled multi-colour effect can be achieved. The controlled multi-colour effect can be obtained with the use of only two different wavelengths. When at least three different wavelengths are used vvhich correspond to the colours in the colour triangle, a controlled fast-colour effect can be achieved. This cannot be obtained with the previously known surface relief structures as the colour dispersion is fixed by the physical principles of the diffraction grating.
With a surface relief, therefore, a rainbow colour spectrum is always generated in the reconstruction with white light. In accordance with the advantageous embodiment of the method of the present invention, controlled colour effects are possible in contrast to those of the prior art methods.
The document or security element can be fabricated in that a volume hologram is fabricated from a surface relief by means of an optical copying process. The surface relied is used as the so-called master. The volume hologram is fabricated from this by means of an optical copying process. But it is also possible to fabricate the volume hologram by means of direct irradiation.
The improved copy protection of the volume holograms is based on the one hand by such volume hologram being able to be reconstructed only in monochrome form. If, therefore, an attempt is made to copy a volume hologram, this can only be successful if exactly the same wavelength of coherent light or laser light is used as in the recording of the volume liologram. Even the, the copying process will only be successful if there is no topical shrinking or swelling in the film material after the recording of the volume hologram.
Based on this, an additional copy protection can be obtained by topical region of the volume hologram which are otherwise not recognisable being shrunk and/or swollen after the recording of the volume hologram so that the Bragg network planes in these regions change correspondingly. A copy of such a volume hologram could only be made with liolographic means by an adaptation of the wavelength, but this is not possible as the topical regions in which the Bragg network planes have been changed are not recognisable to the outside. This means that with an only topical or inhomogeneous shrinking or swelling of the layers (network planes), the volume hologram can only be
The invention further relates to a method for the fabrication of such a document or security element.
Background of the Invention With documents of the most varied type, for example with bank notes, securities or similar documents, a security element is often required which is intended to provide protection against copying. Security elements of this type which comprise an optical grating are well known in the art. In the solutions previously known, optical gratings are used which are designed as surface reliefs. However, the copy protection obtained in this way is not sufficient in all cases.
It is therefore the object of the invention to improve the copy protection in documents with a security element.
Summary of the Invention The present invention relates to an optical grating comprising a volume hologram into which a kinetic effect is introduced. In this way, a substantially greater copy protection can be achieved.
In the fabrication of a volume hologram, a film or another grain-free, translucent, photosensitive medium is irradiated with coherent light, in particular with laser light.
Due to interference in the film material, Bragg network planes are created which embody the information written in the hologram.
(Dne advantageous embodiment is characterised in that the volume hologram has been fabricated with two or more different wavelengths. In this way, a controlled multi-colour effect can be achieved. The controlled multi-colour effect can be obtained with the use of only two different wavelengths. When at least three different wavelengths are used vvhich correspond to the colours in the colour triangle, a controlled fast-colour effect can be achieved. This cannot be obtained with the previously known surface relief structures as the colour dispersion is fixed by the physical principles of the diffraction grating.
With a surface relief, therefore, a rainbow colour spectrum is always generated in the reconstruction with white light. In accordance with the advantageous embodiment of the method of the present invention, controlled colour effects are possible in contrast to those of the prior art methods.
The document or security element can be fabricated in that a volume hologram is fabricated from a surface relief by means of an optical copying process. The surface relied is used as the so-called master. The volume hologram is fabricated from this by means of an optical copying process. But it is also possible to fabricate the volume hologram by means of direct irradiation.
The improved copy protection of the volume holograms is based on the one hand by such volume hologram being able to be reconstructed only in monochrome form. If, therefore, an attempt is made to copy a volume hologram, this can only be successful if exactly the same wavelength of coherent light or laser light is used as in the recording of the volume liologram. Even the, the copying process will only be successful if there is no topical shrinking or swelling in the film material after the recording of the volume hologram.
Based on this, an additional copy protection can be obtained by topical region of the volume hologram which are otherwise not recognisable being shrunk and/or swollen after the recording of the volume hologram so that the Bragg network planes in these regions change correspondingly. A copy of such a volume hologram could only be made with liolographic means by an adaptation of the wavelength, but this is not possible as the topical regions in which the Bragg network planes have been changed are not recognisable to the outside. This means that with an only topical or inhomogeneous shrinking or swelling of the layers (network planes), the volume hologram can only be
2 copied point by point or pixel by pixel; but this requires such a great effort that it is no longer interesting for economic reasons.
On the other hand, the increased copy protection is achieved by the diffraction gratings being very angle-selective in the volume holograms. This means that the volume hologram can only be copied if exactly the same irradiation angle is used as in the recording. Even then, the volume hologram can only be copied with the greatest difficulty - if at all - if it has been applied to a surface which is not exactly smooth; if, fhr example, it has been applied to a document made from paper or to any other not exactly smooth surface. In this way, topical partial regions of the surface possesses angles which differ slightly from one another with only small angle differences being sufficient to make copying impossible. Due to the angle differences which are created by the surface rouglmess, the whole hologram cannot be reconstructed with a plane wave. In the event of attempted copying, this has the result that only parts of the volume hologram are copied and that at those points where no reconstruction of the volume hologram was performed the copied hologram remains unirradiated or that at least a clear colour difference or variation in brightness occurs.
A kinetic or kinematographic effect is introduced or written into the volume hologram.
To generate such kinetic effects, the diffraction structure in the volume hologram is such that patterns which occur at a given direction of illumination and observation move with regard to a coordinate system in a fixed connection with the substrate along a pre-determined path at a predetermined speed when the substrate is moved preferable in its plane, for example is turned in a certain direction of rotation and at a certain speed. By the introduction of such kinetic effects into volume holograms, the copying of these holograms can be made more difficult. Furthermore, in this way a greater recognition value can be provided. In addition, by means of different single irradiations, individual data can be irradiated into the volume hologram as well whereby the security value of the security element in enhanced even further.
On the other hand, the increased copy protection is achieved by the diffraction gratings being very angle-selective in the volume holograms. This means that the volume hologram can only be copied if exactly the same irradiation angle is used as in the recording. Even then, the volume hologram can only be copied with the greatest difficulty - if at all - if it has been applied to a surface which is not exactly smooth; if, fhr example, it has been applied to a document made from paper or to any other not exactly smooth surface. In this way, topical partial regions of the surface possesses angles which differ slightly from one another with only small angle differences being sufficient to make copying impossible. Due to the angle differences which are created by the surface rouglmess, the whole hologram cannot be reconstructed with a plane wave. In the event of attempted copying, this has the result that only parts of the volume hologram are copied and that at those points where no reconstruction of the volume hologram was performed the copied hologram remains unirradiated or that at least a clear colour difference or variation in brightness occurs.
A kinetic or kinematographic effect is introduced or written into the volume hologram.
To generate such kinetic effects, the diffraction structure in the volume hologram is such that patterns which occur at a given direction of illumination and observation move with regard to a coordinate system in a fixed connection with the substrate along a pre-determined path at a predetermined speed when the substrate is moved preferable in its plane, for example is turned in a certain direction of rotation and at a certain speed. By the introduction of such kinetic effects into volume holograms, the copying of these holograms can be made more difficult. Furthermore, in this way a greater recognition value can be provided. In addition, by means of different single irradiations, individual data can be irradiated into the volume hologram as well whereby the security value of the security element in enhanced even further.
3 In a first aspect, the present invention seeks to provide a method of producing a security element for a document comprising the steps of: recording a volume hologram onto a substrate;
introducing a kinetic effect into the volume hologram; performing an operation selected from shrinking local areas of the volume hologram to change Bragg network planes in the local areas, or swelling local areas of the volume hologram to change Bragg network planes in the local areas, and combinations thereof.
According to a first broad aspect of an embodiment of the present invention, there is disclosed a method of producing a security element for a document comprising the steps of (a) recording a volume hologram onto a substrate;
(b) introducing a kinetic effect into the volume hologram;
(c) performing an operation selected from shrinking local areas of the volume hologram to change Bragg network planes in the local areas and swelling local areas of the volume hologram to change Bragg network planes in the local areas.
Brief Description of the Drawings Fig. 1 shows a hologram designed as a surface relief according to the present invention;
Fig. 2 shows a section through a volume hologram of the present invention.
Detailed Description of the Drawings The surface relief shown in Fig. 1 can be applied to a document as a security element. The information in the hologram is stored in the surface structure.
Fig. 2 shows a document with a substrate 1 onto which a volume hologram 2 has been applied.
By means of irradiation, there are created in the film material Bragg network planes nl, n2, etc., which are located at a distance of a/2 (where k is. the wavelength of the light used) and which contain the holographic information.
introducing a kinetic effect into the volume hologram; performing an operation selected from shrinking local areas of the volume hologram to change Bragg network planes in the local areas, or swelling local areas of the volume hologram to change Bragg network planes in the local areas, and combinations thereof.
According to a first broad aspect of an embodiment of the present invention, there is disclosed a method of producing a security element for a document comprising the steps of (a) recording a volume hologram onto a substrate;
(b) introducing a kinetic effect into the volume hologram;
(c) performing an operation selected from shrinking local areas of the volume hologram to change Bragg network planes in the local areas and swelling local areas of the volume hologram to change Bragg network planes in the local areas.
Brief Description of the Drawings Fig. 1 shows a hologram designed as a surface relief according to the present invention;
Fig. 2 shows a section through a volume hologram of the present invention.
Detailed Description of the Drawings The surface relief shown in Fig. 1 can be applied to a document as a security element. The information in the hologram is stored in the surface structure.
Fig. 2 shows a document with a substrate 1 onto which a volume hologram 2 has been applied.
By means of irradiation, there are created in the film material Bragg network planes nl, n2, etc., which are located at a distance of a/2 (where k is. the wavelength of the light used) and which contain the holographic information.
4
Claims (5)
1. A method of producing a security element for a document comprising the steps of:
(a) recording a volume hologram onto a substrate;
(b) introducing a kinetic effect into the volume hologram;
(c) performing an operation selected from shrinking local areas of the volume hologram to change Bragg network planes in the local areas and swelling local areas of the volume hologram to change Bragg network planes in the local areas.
(a) recording a volume hologram onto a substrate;
(b) introducing a kinetic effect into the volume hologram;
(c) performing an operation selected from shrinking local areas of the volume hologram to change Bragg network planes in the local areas and swelling local areas of the volume hologram to change Bragg network planes in the local areas.
2. A method according to claim 1, wherein the volume hologram is recorded onto the substrate from a surface relief by an optical copying process.
3. A method according to claim 2, wherein the volume hologram is recorded using direct light exposure.
4. A method according to claim 3, wherein the volume hologram is recorded using direct light with two or more wavelengths.
5. A document comprising a substrate and a security element produced by the method of any one of claims 1 to 4.
Applications Claiming Priority (4)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE19752704 | 1997-11-27 | ||
| DE19752704.3 | 1997-11-27 | ||
| DE19810134.1 | 1998-03-09 | ||
| DE19810134A DE19810134A1 (en) | 1997-11-27 | 1998-03-09 | Security element for documents and processes for its manufacture |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CA2247974A1 CA2247974A1 (en) | 1999-05-27 |
| CA2247974C true CA2247974C (en) | 2007-09-04 |
Family
ID=26041974
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA002247974A Expired - Lifetime CA2247974C (en) | 1997-11-27 | 1998-09-23 | A security element for documents and a method for its fabrication |
Country Status (9)
| Country | Link |
|---|---|
| EP (1) | EP0919961B1 (en) |
| JP (1) | JPH11240280A (en) |
| CN (1) | CN1113277C (en) |
| AT (1) | ATE242902T1 (en) |
| CA (1) | CA2247974C (en) |
| DK (1) | DK0919961T3 (en) |
| ES (1) | ES2201382T3 (en) |
| HK (1) | HK1020924A1 (en) |
| PT (1) | PT919961E (en) |
Families Citing this family (19)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2801246B1 (en) | 1999-11-19 | 2002-01-25 | Hologram Ind | SECURING DOCUMENTS OR PRODUCTS BY APPOSITION OF AN OPTICALLY ACTIVE COMPONENT FOR AUTHENTICITY VERIFICATION |
| GB0013379D0 (en) | 2000-06-01 | 2000-07-26 | Optaglio Ltd | Label and method of forming the same |
| US7387249B2 (en) | 2000-06-05 | 2008-06-17 | Optaglio Limited | Product verification and authentication system and method |
| GB0016359D0 (en) | 2000-07-03 | 2000-08-23 | Optaglio Ltd | Optical apparatus |
| GB0016354D0 (en) * | 2000-07-03 | 2000-08-23 | Optaglio Ltd | Optical security device |
| GB0016358D0 (en) | 2000-07-03 | 2000-08-23 | Optaglio Ltd | Optical device |
| GB0016356D0 (en) | 2000-07-03 | 2000-08-23 | Optaglio Ltd | Optical structure |
| EP1179810A1 (en) * | 2000-08-11 | 2002-02-13 | European Central Bank, Directorate Banknotes, RDDO | Security documents data exchange system |
| US7576898B2 (en) | 2004-02-17 | 2009-08-18 | E. I. Du Pont De Nemours And Company | Method for using a deep image hologram as a security device and a deep image hologram |
| DE102004012787A1 (en) * | 2004-03-15 | 2005-10-06 | Bundesdruckerei Gmbh | Data carrier and method for producing a data carrier |
| DK1765600T4 (en) † | 2004-06-30 | 2015-05-26 | Kxo Ag | Antiforfalsknings security object and the method for manufacturing and verifying the same |
| DE102007019837A1 (en) | 2007-04-25 | 2008-11-13 | Hologram Industries Research Gmbh | Volume hologram, master for the production of the standard elements of the volume hologram and method for the subsequent hologram individualization when applied to personnel and value documents |
| DE102007025907A1 (en) | 2007-06-01 | 2008-12-11 | Hologram Industries Research Gmbh | Method for producing a multicolor volume hologram, document with such a hologram and volume hologram master |
| DE102007052951B4 (en) | 2007-10-31 | 2021-11-18 | Bundesdruckerei Gmbh | Verification device for a hologram |
| US8742369B2 (en) | 2010-11-01 | 2014-06-03 | Honeywell International Inc. | Value documents and other articles having taggants that exhibit delayed maximum intensity emissions, and methods and apparatus for their authentication |
| RU2015109872A (en) * | 2012-08-23 | 2016-10-10 | Байер Матириальсайенс Аг | PROTECTED DOCUMENT AND / OR SECURITIES CONTAINING A VISUALLY CHANGE HOLOGRAM WINDOW |
| DE102012020257A1 (en) | 2012-10-16 | 2014-04-17 | Giesecke & Devrient Gmbh | Optically variable surface pattern |
| DE102013217291A1 (en) | 2013-08-29 | 2015-03-05 | Bundesdruckerei Gmbh | Method for decentralizing a security document |
| DE102022206277A1 (en) | 2022-06-22 | 2023-12-28 | Carl Zeiss Jena Gmbh | MASTER PLATE FOR HOLOGRAM REPLICATION |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| AU584035B2 (en) * | 1985-03-01 | 1989-05-11 | Kenneth John Hayden | Holographic security devices and systems |
| US4832445A (en) * | 1986-05-16 | 1989-05-23 | American Bank Note Holographics, Inc. | Security diffraction devices difficult to exactly duplicate |
| ATE98795T1 (en) * | 1988-09-30 | 1994-01-15 | Landis & Gyr Business Support | DIFFRACTION ELEMENT. |
| US5221957A (en) * | 1990-01-12 | 1993-06-22 | Physical Optics Corporation | Nonuniform holographic filter in a spectroscopic system |
-
1998
- 1998-08-31 AT AT98116431T patent/ATE242902T1/en active
- 1998-08-31 EP EP98116431A patent/EP0919961B1/en not_active Expired - Lifetime
- 1998-08-31 DK DK98116431T patent/DK0919961T3/en active
- 1998-08-31 ES ES98116431T patent/ES2201382T3/en not_active Expired - Lifetime
- 1998-08-31 PT PT98116431T patent/PT919961E/en unknown
- 1998-09-23 CA CA002247974A patent/CA2247974C/en not_active Expired - Lifetime
- 1998-10-10 CN CN98124631A patent/CN1113277C/en not_active Expired - Lifetime
- 1998-11-09 JP JP31769198A patent/JPH11240280A/en active Pending
-
1999
- 1999-12-15 HK HK99105900A patent/HK1020924A1/en not_active IP Right Cessation
Also Published As
| Publication number | Publication date |
|---|---|
| JPH11240280A (en) | 1999-09-07 |
| EP0919961B1 (en) | 2003-06-11 |
| EP0919961A2 (en) | 1999-06-02 |
| CA2247974A1 (en) | 1999-05-27 |
| CN1113277C (en) | 2003-07-02 |
| CN1222455A (en) | 1999-07-14 |
| ES2201382T3 (en) | 2004-03-16 |
| DK0919961T3 (en) | 2003-09-08 |
| ATE242902T1 (en) | 2003-06-15 |
| HK1020924A1 (en) | 2000-05-26 |
| PT919961E (en) | 2003-10-31 |
| EP0919961A3 (en) | 2000-01-12 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| EEER | Examination request | ||
| MKEX | Expiry |
Effective date: 20180924 |