CA1295030C - Antipilferage systems - Google Patents
Antipilferage systemsInfo
- Publication number
- CA1295030C CA1295030C CA000591687A CA591687A CA1295030C CA 1295030 C CA1295030 C CA 1295030C CA 000591687 A CA000591687 A CA 000591687A CA 591687 A CA591687 A CA 591687A CA 1295030 C CA1295030 C CA 1295030C
- Authority
- CA
- Canada
- Prior art keywords
- coil
- field generator
- magnetic field
- coils
- detection
- 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
Classifications
-
- G—PHYSICS
- G08—SIGNALLING
- G08B—SIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
- G08B13/00—Burglar, theft or intruder alarms
- G08B13/22—Electrical actuation
- G08B13/24—Electrical actuation by interference with electromagnetic field distribution
- G08B13/2402—Electronic Article Surveillance [EAS], i.e. systems using tags for detecting removal of a tagged item from a secure area, e.g. tags for detecting shoplifting
- G08B13/2405—Electronic Article Surveillance [EAS], i.e. systems using tags for detecting removal of a tagged item from a secure area, e.g. tags for detecting shoplifting characterised by the tag technology used
- G08B13/2408—Electronic Article Surveillance [EAS], i.e. systems using tags for detecting removal of a tagged item from a secure area, e.g. tags for detecting shoplifting characterised by the tag technology used using ferromagnetic tags
-
- G—PHYSICS
- G08—SIGNALLING
- G08B—SIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
- G08B13/00—Burglar, theft or intruder alarms
- G08B13/22—Electrical actuation
- G08B13/24—Electrical actuation by interference with electromagnetic field distribution
- G08B13/2402—Electronic Article Surveillance [EAS], i.e. systems using tags for detecting removal of a tagged item from a secure area, e.g. tags for detecting shoplifting
- G08B13/2428—Tag details
- G08B13/2437—Tag layered structure, processes for making layered tags
-
- G—PHYSICS
- G08—SIGNALLING
- G08B—SIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
- G08B13/00—Burglar, theft or intruder alarms
- G08B13/22—Electrical actuation
- G08B13/24—Electrical actuation by interference with electromagnetic field distribution
- G08B13/2402—Electronic Article Surveillance [EAS], i.e. systems using tags for detecting removal of a tagged item from a secure area, e.g. tags for detecting shoplifting
- G08B13/2428—Tag details
- G08B13/2437—Tag layered structure, processes for making layered tags
- G08B13/2442—Tag materials and material properties thereof, e.g. magnetic material details
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
- H01F5/00—Coils
- H01F5/003—Printed circuit coils
Abstract
ABSTRACT
ANTIPILFERAGE SYSTEMS
An antipilferage system for the detection of magnetic tags comprise an assembly of spirally wound emitter and/or detector coils. This arrangement enables a tag to be detected regardless of its orientation.
ANTIPILFERAGE SYSTEMS
An antipilferage system for the detection of magnetic tags comprise an assembly of spirally wound emitter and/or detector coils. This arrangement enables a tag to be detected regardless of its orientation.
Description
1~35~
ANTIPILFERAGE SYSTEMS
This invention relates to antipilferage systems and to devices for use therein.
Antipilferage tags or markers are applied to articles of commerce ln order to protect them from theft at the point of sale premises. Typically, the tag is a magnetic medium which is deactivated when a shop assistant carriers out the routine procedure at the time of effecting a sale.
Such deactivation prevents detection of the magnetic tag when it (and the article to which it is attached) pass through a detection system, typically in the form of a walk-through framework which emits an alternating magnetic interrogation field. This field is designed to interact with a tag and to respond by, for example, emitting a warning signal in the event that detection of a non-deactivated tag ocaurs.
A problem which occurs ~requently with conventional antipilferage systems is that an adequate detection signal is only available if a non-deactivated tag passes through the interrogation gate in the correct orientation. Normal interrogating gates contain coils which generate a magnetic field principally alony the axis of the coil.
The magnetic tags are also usually unidirectionally sensitive. Thus generally, the major axis of the tag needs to be aligned perpendicularly with respect to the plane of the coils (i.e. along the coil axis~ which produce the interrogating field if the tag is to be detected. Consequently, it is by no means unusual for the antipilferage system to fail to detect certain items which are removed from the store without first having gone through the proper sales procedure simply because of the orientation of the tag on the article as it is moved through the interrogating field.
We have now devised an alternative to the usual interrogating gate system as employed at or near the point 3~
;~
of sale in stores. The principal element o~ this alternative system can be constructed as a walk-through framework, or as a hand-held item, the net response of which is not orientation-dependent. More particularly, according to one aspect of the present invention, there is provided an interrogating system for use in an antipilferage system, which is characterised in that the interrogating system comprises a magnetic field generator which is in the form of a substantially planar spirally wound coil or of a coil which is wound so as to approximate to a spiral. The system also includes means for detecting the response of a magnetic tag po~itioned within the effective field generated by said magnetic field generator, said detection means comprising one or more pairs of coils wound spirally or wound so as to approximate to a spiral winding, and positioned so as to overlay the maqnetic field generator coil. Such overlay should preferably be exactly symmetrical and the phasing of the windings such that the net signal coupled directly from the field generator coil is near to zero. This arrangement greatly simplifies the filtering normally required at the receiver input to prevent overloading by directly coupled signals. It also enables the overall sensitivity to be tailored such that it is similar for labels in any orientation.
Preferably, the magnetic field generator coil and/or the detection coils are formed by photolithographic techniques such as are used in the production of printed circuit boards. The use of these techniques allows very precise mutual orientation between the omitting coil (on one side of the card or device) and the detecting coils (on the other side of the card or device). An arrangement of generator coil and detection coils is hereinafter referred to as a coil assembly.
~L295~3() The whole system is preferably constructed as an array of such coll assemblies which, in use, is positioned close to a point of sale such that customers and/or items to be checked will pass close to the array. Alternatively, a hand-held unit based on a single coil assembly (magnetic field generator coil and detection coils) is moved over the person to locate any concealed items carrying non-deactivated tags.
As used herein, the term "spiral" is not restricted to circular spirals, but also encompass~s within its scope square, rectangular, oval and other simple spiral arrangements as well as more complicated shapes r provided that there is substantial adjacency in a common plane between successive turns or courses of the winding.
One particular advantage of a flat spiral coil configuration in accordance with this invention over a conventional pile-wound coil of constant radius :is its ease of automated manufacture. Another important advantage is that there is an improved magnetic field patternv In particular, there is much less curvature of the principal component of the field pattern in the area immediately above the windings. This improves the maximum coupling possible between the coils and a magnetic label in the vicinity of the coils. Since the overall sensitivity pattern of a generator/detector coil pair depends on their mutual arrangement, it is easy to arrange the areas and the overlaps o the two spiral windings to produce similar sensitivities for magnetic labels in any orientation.
With a detection device in accordance with this invention, a magnetic tag which has not been deactivated will give a response regardless of its orientation wit~
respect to the device, at least at one point in a plane parallel to the surface of the spiral. It is thus possible to configure adjacent rows of suitably ,~( ~2~ i313 dimensioned coil assemblies such that a tag in any orientation wh.ich moves in a plane parallel to the array will be detected at some point(s) in its travel over the plane.
In those embodiments of the invention which take the form of a hand-held device, a single coil assembly will detect a tag in any orientation if it is scanned in a suitable fashion in a plane parallel to that in which the tag lies. A suitable scan would be a simple meander with dimensions of the same order as the coil dimensions.
An exemplary embodiment of the present invention is shown in the accompanying drawings, in which:
Figure 1 is a plan view of a spirally wound 10emitter coil; and Figure 2 is a plan view of spirally wound detector coils.
In the preferred embodiment each coil assembly comprises a generator coil 1 as shown in Figure 1 which is formed by photolithographic techniques as a planar spiral on a card 2 and two detector coils 3a, 3b arranged on the other side of the card 2 so as to overlay the generator coil 1. Each detector coil is similarly formed as a planar spiral.
One particular type of EAS label utilises a strip of amorphous ferromagnetic alloy about 30cm long. For a hand-held detector application a coil assembly with a total dimension of 160mm x 160mm x lmm thick, with about 30 turns in the emitting coil, and 2 x 60 turns in the detecting coil has been fabricated frQm double sides copper~clad fibre-glass printed circuit board. Using a processing system based on detection of high-order harmonics of a low level 5KHz interrogating field, and simple band-pass filtering, detection of labels in all orientations at a maximum distance of 100 +10mm has been demonstrated.
X
.
ANTIPILFERAGE SYSTEMS
This invention relates to antipilferage systems and to devices for use therein.
Antipilferage tags or markers are applied to articles of commerce ln order to protect them from theft at the point of sale premises. Typically, the tag is a magnetic medium which is deactivated when a shop assistant carriers out the routine procedure at the time of effecting a sale.
Such deactivation prevents detection of the magnetic tag when it (and the article to which it is attached) pass through a detection system, typically in the form of a walk-through framework which emits an alternating magnetic interrogation field. This field is designed to interact with a tag and to respond by, for example, emitting a warning signal in the event that detection of a non-deactivated tag ocaurs.
A problem which occurs ~requently with conventional antipilferage systems is that an adequate detection signal is only available if a non-deactivated tag passes through the interrogation gate in the correct orientation. Normal interrogating gates contain coils which generate a magnetic field principally alony the axis of the coil.
The magnetic tags are also usually unidirectionally sensitive. Thus generally, the major axis of the tag needs to be aligned perpendicularly with respect to the plane of the coils (i.e. along the coil axis~ which produce the interrogating field if the tag is to be detected. Consequently, it is by no means unusual for the antipilferage system to fail to detect certain items which are removed from the store without first having gone through the proper sales procedure simply because of the orientation of the tag on the article as it is moved through the interrogating field.
We have now devised an alternative to the usual interrogating gate system as employed at or near the point 3~
;~
of sale in stores. The principal element o~ this alternative system can be constructed as a walk-through framework, or as a hand-held item, the net response of which is not orientation-dependent. More particularly, according to one aspect of the present invention, there is provided an interrogating system for use in an antipilferage system, which is characterised in that the interrogating system comprises a magnetic field generator which is in the form of a substantially planar spirally wound coil or of a coil which is wound so as to approximate to a spiral. The system also includes means for detecting the response of a magnetic tag po~itioned within the effective field generated by said magnetic field generator, said detection means comprising one or more pairs of coils wound spirally or wound so as to approximate to a spiral winding, and positioned so as to overlay the maqnetic field generator coil. Such overlay should preferably be exactly symmetrical and the phasing of the windings such that the net signal coupled directly from the field generator coil is near to zero. This arrangement greatly simplifies the filtering normally required at the receiver input to prevent overloading by directly coupled signals. It also enables the overall sensitivity to be tailored such that it is similar for labels in any orientation.
Preferably, the magnetic field generator coil and/or the detection coils are formed by photolithographic techniques such as are used in the production of printed circuit boards. The use of these techniques allows very precise mutual orientation between the omitting coil (on one side of the card or device) and the detecting coils (on the other side of the card or device). An arrangement of generator coil and detection coils is hereinafter referred to as a coil assembly.
~L295~3() The whole system is preferably constructed as an array of such coll assemblies which, in use, is positioned close to a point of sale such that customers and/or items to be checked will pass close to the array. Alternatively, a hand-held unit based on a single coil assembly (magnetic field generator coil and detection coils) is moved over the person to locate any concealed items carrying non-deactivated tags.
As used herein, the term "spiral" is not restricted to circular spirals, but also encompass~s within its scope square, rectangular, oval and other simple spiral arrangements as well as more complicated shapes r provided that there is substantial adjacency in a common plane between successive turns or courses of the winding.
One particular advantage of a flat spiral coil configuration in accordance with this invention over a conventional pile-wound coil of constant radius :is its ease of automated manufacture. Another important advantage is that there is an improved magnetic field patternv In particular, there is much less curvature of the principal component of the field pattern in the area immediately above the windings. This improves the maximum coupling possible between the coils and a magnetic label in the vicinity of the coils. Since the overall sensitivity pattern of a generator/detector coil pair depends on their mutual arrangement, it is easy to arrange the areas and the overlaps o the two spiral windings to produce similar sensitivities for magnetic labels in any orientation.
With a detection device in accordance with this invention, a magnetic tag which has not been deactivated will give a response regardless of its orientation wit~
respect to the device, at least at one point in a plane parallel to the surface of the spiral. It is thus possible to configure adjacent rows of suitably ,~( ~2~ i313 dimensioned coil assemblies such that a tag in any orientation wh.ich moves in a plane parallel to the array will be detected at some point(s) in its travel over the plane.
In those embodiments of the invention which take the form of a hand-held device, a single coil assembly will detect a tag in any orientation if it is scanned in a suitable fashion in a plane parallel to that in which the tag lies. A suitable scan would be a simple meander with dimensions of the same order as the coil dimensions.
An exemplary embodiment of the present invention is shown in the accompanying drawings, in which:
Figure 1 is a plan view of a spirally wound 10emitter coil; and Figure 2 is a plan view of spirally wound detector coils.
In the preferred embodiment each coil assembly comprises a generator coil 1 as shown in Figure 1 which is formed by photolithographic techniques as a planar spiral on a card 2 and two detector coils 3a, 3b arranged on the other side of the card 2 so as to overlay the generator coil 1. Each detector coil is similarly formed as a planar spiral.
One particular type of EAS label utilises a strip of amorphous ferromagnetic alloy about 30cm long. For a hand-held detector application a coil assembly with a total dimension of 160mm x 160mm x lmm thick, with about 30 turns in the emitting coil, and 2 x 60 turns in the detecting coil has been fabricated frQm double sides copper~clad fibre-glass printed circuit board. Using a processing system based on detection of high-order harmonics of a low level 5KHz interrogating field, and simple band-pass filtering, detection of labels in all orientations at a maximum distance of 100 +10mm has been demonstrated.
X
.
Claims (5)
1. An interrogating system for use in an antipilferage system, wherein the interrogating system comprises a magnetic field generator which is in the form of a substantially planar spirally wound coil and means for detecting the response of a magnetic tag positioned within the effective field generated by said magnetic field generator, said detection means comprising one or more pairs of coils wound spirally and positioned so as to overlay the magnetic field generator coil.
2. A system as claimed in claim 1 in which said overlay is exactly symmetrical and the phasing of the windings is such that the net signal coupled directly from the field generator coil is near to zero.
3. A system as claimed in claim 1 in which the magnetic field generator coil and/or the detection coils are formed by photolithographic techniques.
4. A system as claimed in claim 1, 2 or 3 which is constructed as an array of such coils and which, in use, is positioned close to a point of sale such that customers and/or items to be checked will pass close to the array.
5. A system as claimed in claim 1, 2 or 3 which comprises a hand-held unit based on a single coil assembly of magnetic field generator coil and detection coils.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GBGB8808933.9 | 1988-04-15 | ||
| GB888808933A GB8808933D0 (en) | 1988-04-15 | 1988-04-15 | Antipilferage system |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1295030C true CA1295030C (en) | 1992-01-28 |
Family
ID=10635253
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000591687A Expired - Lifetime CA1295030C (en) | 1988-04-15 | 1989-02-21 | Antipilferage systems |
Country Status (12)
| Country | Link |
|---|---|
| US (1) | US5049856A (en) |
| EP (1) | EP0338660B1 (en) |
| JP (1) | JP2604477B2 (en) |
| AT (1) | ATE95930T1 (en) |
| AU (1) | AU608431B2 (en) |
| BR (1) | BR8906849A (en) |
| CA (1) | CA1295030C (en) |
| DE (1) | DE68909830T2 (en) |
| DK (1) | DK637089D0 (en) |
| GB (1) | GB8808933D0 (en) |
| NO (1) | NO895036D0 (en) |
| WO (1) | WO1989009983A1 (en) |
Families Citing this family (18)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2662320B1 (en) * | 1990-05-18 | 1994-05-13 | Cemagref | CONTACTLESS CONNECTION DEVICE FOR CONNECTING SERIES BUS LINES. |
| JPH04245410A (en) * | 1991-01-30 | 1992-09-02 | Sharp Corp | Printed coil for double-tuned circuit use |
| ATE201787T1 (en) * | 1992-11-25 | 2001-06-15 | Simmonds Precision Products | DATA PROCESSING STRUCTURES AND METHODS |
| GB9305085D0 (en) * | 1993-03-12 | 1993-04-28 | Esselte Meto Int Gmbh | Electronic article surveillance system with enhanced geometric arrangement |
| US5581248A (en) * | 1993-06-14 | 1996-12-03 | Simmonds Precision Products, Inc. | Embeddable device for contactless interrogation of sensors for smart structures |
| US5433115A (en) * | 1993-06-14 | 1995-07-18 | Simmonds Precision Products, Inc. | Contactless interrogation of sensors for smart structures |
| US5515041A (en) * | 1993-06-14 | 1996-05-07 | Simmonds Precision Products Inc. | Composite shaft monitoring system |
| US5602540A (en) * | 1993-06-14 | 1997-02-11 | Simmonds Precision Products Inc. | Fluid gauging apparatus with inductive interrogation |
| DE19503896A1 (en) * | 1995-02-07 | 1996-08-08 | Esselte Meto Int Gmbh | Device for detecting an article provided with an electronic security element |
| US5508684A (en) * | 1995-03-02 | 1996-04-16 | Becker; Richard S. | Article tag |
| US5717381A (en) * | 1995-12-21 | 1998-02-10 | Eastman Kodak Company | Copyright protection for photos and documents using magnetic elements |
| US6060988A (en) * | 1997-02-03 | 2000-05-09 | Sensormatic Electronics Corporation | EAS marker deactivation device having core-wound energized coils |
| US5867101A (en) * | 1997-02-03 | 1999-02-02 | Sensormatic Electronics Corporation | Multi-phase mode multiple coil distance deactivator for magnetomechanical EAS markers |
| US6289141B1 (en) * | 1998-01-15 | 2001-09-11 | Morton F. Roseman | Apparatus for authenticating products and authorizing processes using the magnetic properties of a marker |
| GB9815118D0 (en) * | 1998-07-14 | 1998-09-09 | Clan Holdings Ltd | Security tag |
| EP1195714A1 (en) * | 2000-10-04 | 2002-04-10 | Sokymat S.A. | Transponder unit |
| US20060180094A1 (en) * | 2005-02-15 | 2006-08-17 | Viggiano Gregory R | Pet containment apparatus and method |
| KR102257892B1 (en) * | 2014-11-26 | 2021-05-28 | 삼성전자주식회사 | Advanced NFC Antenna and Electronic Device with the same |
Family Cites Families (23)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| AU451179B2 (en) * | 1973-03-23 | 1974-08-01 | Knogo Corporation | System for article theft detection |
| US4135183A (en) * | 1977-05-24 | 1979-01-16 | Minnesota Mining And Manufacturing Company | Antipilferage system utilizing "figure-8" shaped field producing and detector coils |
| US4263553A (en) * | 1978-05-30 | 1981-04-21 | Cook Kenneth M | Discriminating metal detector with compensation for ground minerals |
| JPS622733Y2 (en) * | 1978-09-11 | 1987-01-22 | ||
| US4305785A (en) * | 1980-02-26 | 1981-12-15 | The United States Of America As Represented By The United States Department Of Energy | Sensor for detecting changes in magnetic fields |
| GB2110825B (en) * | 1981-11-06 | 1986-04-30 | Outokumpu Oy | Apparatus for detecting metal objects |
| US4482874A (en) * | 1982-06-04 | 1984-11-13 | Minnesota Mining And Manufacturing Company | Method of constructing an LC network |
| US4623877A (en) * | 1983-06-30 | 1986-11-18 | Knogo Corporation | Method and apparatus for detection of targets in an interrogation zone |
| US4578654A (en) * | 1983-11-16 | 1986-03-25 | Minnesota Mining And Manufacturing Company | Distributed capacitance lc resonant circuit |
| US4598276A (en) * | 1983-11-16 | 1986-07-01 | Minnesota Mining And Manufacturing Company | Distributed capacitance LC resonant circuit |
| US4541559A (en) * | 1983-11-16 | 1985-09-17 | Minnesota Mining And Manufacturing Company | Method of making electrical connections between opposing metal foils having a flexible, insulating layer sandwiched therebetween |
| DK163151C (en) * | 1983-11-16 | 1992-06-22 | Minnesota Mining & Mfg | LABEL PLATE WITH LC RESONANCE CIRCUIT FOR USE IN ELECTRONIC OBJECT MONITORING SYSTEM, METHOD FOR MANUFACTURING BOTTLE PLATES, AND ELECTRONIC OBJECT MONITORING SYSTEM THEREOF. |
| US4583099A (en) * | 1983-12-27 | 1986-04-15 | Polyonics Corporation | Resonant tag circuits useful in electronic security systems |
| US4647917A (en) * | 1984-03-26 | 1987-03-03 | Allied Corporation | Article control system having coded magnetomechanical marker |
| US4618822A (en) * | 1984-04-18 | 1986-10-21 | Position Orientation Systems, Ltd. | Displacement sensing device utilizing adjustable tuned circuit |
| US4634975A (en) * | 1984-09-17 | 1987-01-06 | Progressive Dynamics, Inc. | Method and apparatus for producing electromagnetic surveillance fields |
| US4613843A (en) * | 1984-10-22 | 1986-09-23 | Ford Motor Company | Planar coil magnetic transducer |
| US4633250A (en) * | 1985-01-07 | 1986-12-30 | Allied Corporation | Coplanar antenna for proximate surveillance systems |
| US4658241A (en) * | 1985-09-17 | 1987-04-14 | Allied Corporation | Surveillance system including transmitter and receiver synchronized by power line zero crossings |
| US4769631A (en) * | 1986-06-30 | 1988-09-06 | Sensormatic Electronics Corporation | Method, system and apparatus for magnetic surveillance of articles |
| US4837568A (en) * | 1987-07-08 | 1989-06-06 | Snaper Alvin A | Remote access personnel identification and tracking system |
| US4866424A (en) * | 1988-01-11 | 1989-09-12 | Eg&G Astrophysics Research Corporation | Metal detector coil |
| US4791412A (en) * | 1988-01-28 | 1988-12-13 | Controlled Information Corporation | Magnetic article surveillance system and method |
-
1988
- 1988-04-15 GB GB888808933A patent/GB8808933D0/en active Pending
-
1989
- 1989-02-20 WO PCT/GB1989/000164 patent/WO1989009983A1/en unknown
- 1989-02-20 JP JP1503225A patent/JP2604477B2/en not_active Expired - Fee Related
- 1989-02-20 AU AU32881/89A patent/AU608431B2/en not_active Ceased
- 1989-02-20 BR BR898906849A patent/BR8906849A/en unknown
- 1989-02-20 EP EP89301644A patent/EP0338660B1/en not_active Expired - Lifetime
- 1989-02-20 DE DE89301644T patent/DE68909830T2/en not_active Expired - Fee Related
- 1989-02-20 AT AT89301644T patent/ATE95930T1/en not_active IP Right Cessation
- 1989-02-21 CA CA000591687A patent/CA1295030C/en not_active Expired - Lifetime
- 1989-12-04 US US07/445,765 patent/US5049856A/en not_active Expired - Lifetime
- 1989-12-14 NO NO895036A patent/NO895036D0/en unknown
- 1989-12-15 DK DK637089A patent/DK637089D0/en not_active Application Discontinuation
Also Published As
| Publication number | Publication date |
|---|---|
| NO895036L (en) | 1989-12-14 |
| DK637089A (en) | 1989-12-15 |
| JPH02504438A (en) | 1990-12-13 |
| DE68909830T2 (en) | 1994-02-10 |
| DE68909830D1 (en) | 1993-11-18 |
| US5049856A (en) | 1991-09-17 |
| EP0338660B1 (en) | 1993-10-13 |
| JP2604477B2 (en) | 1997-04-30 |
| AU608431B2 (en) | 1991-03-28 |
| BR8906849A (en) | 1990-12-04 |
| EP0338660A1 (en) | 1989-10-25 |
| WO1989009983A1 (en) | 1989-10-19 |
| NO895036D0 (en) | 1989-12-14 |
| GB8808933D0 (en) | 1988-05-18 |
| AU3288189A (en) | 1989-11-03 |
| DK637089D0 (en) | 1989-12-15 |
| ATE95930T1 (en) | 1993-10-15 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKLA | Lapsed |