CA1214805A - Method of rendering documents resistant to photocopying and anti-photocopying paper therefor - Google Patents
Method of rendering documents resistant to photocopying and anti-photocopying paper thereforInfo
- Publication number
- CA1214805A CA1214805A CA000434210A CA434210A CA1214805A CA 1214805 A CA1214805 A CA 1214805A CA 000434210 A CA000434210 A CA 000434210A CA 434210 A CA434210 A CA 434210A CA 1214805 A CA1214805 A CA 1214805A
- Authority
- CA
- Canada
- Prior art keywords
- light
- document
- millimicrons
- wavelength
- spectral response
- 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
Links
Classifications
-
- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
- G03G21/00—Arrangements not provided for by groups G03G13/00 - G03G19/00, e.g. cleaning, elimination of residual charge
- G03G21/04—Preventing copies being made of an original
- G03G21/043—Preventing copies being made of an original by using an original which is not reproducible or only reproducible with a different appearence, e.g. originals with a photochromic layer or a colour background
Landscapes
- General Physics & Mathematics (AREA)
- Physics & Mathematics (AREA)
- Paper (AREA)
- Non-Silver Salt Photosensitive Materials And Non-Silver Salt Photography (AREA)
- Credit Cards Or The Like (AREA)
- Printing Methods (AREA)
- Cleaning In Electrography (AREA)
- Pharmaceuticals Containing Other Organic And Inorganic Compounds (AREA)
- Inspection Of Paper Currency And Valuable Securities (AREA)
- Ink Jet Recording Methods And Recording Media Thereof (AREA)
- Compositions Of Oxide Ceramics (AREA)
- Medicines Containing Plant Substances (AREA)
- Saccharide Compounds (AREA)
- Acyclic And Carbocyclic Compounds In Medicinal Compositions (AREA)
Abstract
ABSTRACT OF THE DISCLOSURE
A document has information appearing thereon, with at least a portion of the information being located on a front face of a portion of the document. The front face portion has a colour with a sufficiently low reflection spectral response to render the document portion substan-tially incapable of being photocopied in an information-readable manner. The document portion is capable of trans-mitting visible light from the rear face to the front face to cause sufficient contrast between the relatively non-translucent information and the transmitted light to enable the information to be read by a human eye viewing the front face of the document when visible light is transmitted through the document from the rear face to the front face.
A document has information appearing thereon, with at least a portion of the information being located on a front face of a portion of the document. The front face portion has a colour with a sufficiently low reflection spectral response to render the document portion substan-tially incapable of being photocopied in an information-readable manner. The document portion is capable of trans-mitting visible light from the rear face to the front face to cause sufficient contrast between the relatively non-translucent information and the transmitted light to enable the information to be read by a human eye viewing the front face of the document when visible light is transmitted through the document from the rear face to the front face.
Description
~2~4l30S
This invention relates to rendering documents resistant to photocopying, and inter alia provides an extremely novel and useful anti-photocopying paper.
The present day ready availability of photo-copiers has given rise to the problem of rendering documents or portions thereof resistant to photocopying. It is now unduly easy for a person to make an anauthorized photocopy of a document carrying confidential information, unless the document is resistant to photocopying. Various attempts have been made to render documents resistant to photocopying by covering information on a document with a transparent film which permits the information to be seen by the human eye but which prevents an adequate photocopy being made. United States patents Nos. 3,887,742 and 4,118,122 disclose proposals of this kind but for one reason or another, neither of these proposals provides a satisfactory solution to the problem of rendering documents resistant to photocopying.
Our Canadian Patent No. 1,187,914 issued May 28, 1985 discloses and claims (inter alia) an antiphoto-copying paper which has substantial advantages over the prior art. The antiphotocopying paper which is the subject of Canadian Patent No. 1,187,914 has a colour with a reflection spectral response of less than about 10~ for light with a wavelength below about 600 millimicrons and yet which is sufficiently visually contrasting with in-formation, when the information is typed thereon or other-wise applied thereto, to enable the information to be read by the human eye when the paper is viewed under white light.
We have now discovered an even more improved manner - 1 - ~
, ~ .
~L21~&~?5 of rendering documents resistant to photocopying.
In accordance with this further invention, a docu-ment has information appearing thereon with at least a portion of the information being located on a front face of the por-tion of the document, and the front face portion has a colour with a sufficiently low reflection spectral response to render the document portion substantially incapable of being photo-copied in an information-readable manner, that is to say with the information having a similar low reflection spectral res-ponse, and said document portion being capable of transmittingvisible light from the rear face to the front face to cause sufficient contrast between the relatively non-translucent information and the transmitted light to enable the informa-tion to be read by a human eye viewing the front face of the document when visible light is transmitted through the docu-ment from the rear face to the front face thereof.
The reflection spectral response is advantageously substantially zero for light with a wavelength below about 625 millimicrons, preferably substantially zero for light with a wavelength below about 650 millimicrons, and more prefer-ably substantially zero for light with a wavelength below about 700 millimicrons.
The portion of the document carrying information which is not to be photocopied preferably has a transmission factor averaging 3~ in the visible light range. Advantageously, the transmission factor ranges from substantially zero for light with a wavelength of about 450 millimicrons to about 5%
for light with a wavelength of about 700 millimicrons. Usually, the information will be in a substantially black relatively non-translucent colour.
~L21~80~
Thus, in accordance with the present invention, the document is particularly resistant to photocopying since photocopiers require the document to have an adequate reflec-tion spectral response for light of wavelengths to which the photocopier responds. Most photocopiers do not respond to light with a wavelength above about 625 millimicrons, and are most unlikely to respond to light with a wavelength above about 650 millimicrons. A document in accordance with the present invention therefore is very effectively resistant to photocopying.
On the other hand, a document in accordance with the present invention can be very easily read by means of visible light transmitted through the document from the rear. The visible light may simply be daylight or other ambient light or may be a light which is specifically intended for reading a document in accordance with the present invention. The low reflection spectral response may be provided by applying a suitable ink to a suitable paper or by applying a sui-table pre-manufactured colour film to a suitable paper.
One embodiment of the present invention will now be described by way of example, with reference to the accompany-ing drawings, of which:
Figure 1 is a graph showing the reflection spectral response and transmission factor of anti-photocopying paper in accordance with one embodiment of the invention, and also show-ing the average spectral response of the human eye and a typical spectral response of a photocopier, and Figure 2 is a graph showing the readability of ~L2~4~QS
information on the paper when viewed by means of reflec~ed incident light and by means of transmitted light.
Referring first to Figure 1, a document comprises a sheet of coloured paper having a transmission factor indi-cated by the iine T and a reflection spectral response in-dicated by the line R. Figure 1 also shows the typical spectral response of the human eye by the line E and a pos-sible spectral response of a photocopier by the line P.
It will be noted that the line P indicates that the spectral response of the photocopier decreases to zero at a wavelength of about 650 millimicrons, with a cut-off at about 625 millimicrons, the term "cut-off" being usually applied to the wavelength at which the spectral response has fallen to less than about 10~.
The transmission factor T of the paper increases substantially linearly from zero at a wavelength of about 450 millimicrons to about 5% at a wavelength of about 700 millimicrons, therefore averaging about 3% over the visible light range encompassed by the line E. Above the visible light range, the transmission factor increases substantially linearly to about 10% for light with a wavelength of about 1,000 millimicrons.
The reflection spectral response R is very low (substantially zero) below about 700 millimicronst i.e. less than about 1%, and is also of this order at wavelengths above 700 millimicrons up to about 1,000 millimicrons.
The paper may for example be that sold by Kimberley Clark Corporation under the trade mark W ULTRA II covered on the front face with matt finished "black" ink (such as produced by Cal/Ink Limited or Sinclair & Valentine Limited) to give the required transmission factor.
Information is then typed, printed or otherwise applied in black or similar dark colour on the front face of the paper so that it is relatively non-translucent. Any kind of information may of course be applied, including printed, written or drawn text, graphs or illustrations.
Frequently, the information may be applied to the paper by means of a photocopier from an original document which is not resistant to photocopying. In such a case, anti-photo-copying paper in accordance with the invention will be used as the copy paper in a photocopying machine, with the result that the information will appear on the paper as baked black carbon deposits.
If an attempt is made to photocopy the resultant document, the photocopy will be unreadable because the information on the photocopy will not be distinguishable from the background. In other words, the photocopy will show the background in the same colour as the information since the reflection spectral response of the paper is sub-stantially zero below about 700 millimicrons.
On the other hand, if the document is illustrated from behind, either by positioning the document so that ambient daylight or artificial light or special artificial light passes therethrough from behind, the information can be easily read by the human eye when viewed from the front because the black or substantially black information will be sufficiently contrasting with the background which is lightened by the transmitted light.
Figure 2 shows the relative eye response when i21~
viewing the document. Line 1 shows the eye response to view-ing by light transmitted through the paper, and line 2 shows the eye response to viewing by reflected incident light. When viewing by transmitted light, the transmitted light is easily seen in contrast to the information, particularly at wave-lengths to which the human eye is most responsive as indi-cated by line E in Figure 1. With reflected light, the eye merely perceives the paper to be substantially black and sub-stantially indistinguishable from the information.
The invention is of course applicable to any security documents, including lottery tickets, show and sports events tickets, postal and fiscal stamps, stock shares and bond certificates, credit cards, person~l and bank cheques, travellers cheques and bank notes.
Other embodiments and examples of the invention will be readily apparent to a person skilled in the art, the scope of the invention being defined in the appended claims.
This invention relates to rendering documents resistant to photocopying, and inter alia provides an extremely novel and useful anti-photocopying paper.
The present day ready availability of photo-copiers has given rise to the problem of rendering documents or portions thereof resistant to photocopying. It is now unduly easy for a person to make an anauthorized photocopy of a document carrying confidential information, unless the document is resistant to photocopying. Various attempts have been made to render documents resistant to photocopying by covering information on a document with a transparent film which permits the information to be seen by the human eye but which prevents an adequate photocopy being made. United States patents Nos. 3,887,742 and 4,118,122 disclose proposals of this kind but for one reason or another, neither of these proposals provides a satisfactory solution to the problem of rendering documents resistant to photocopying.
Our Canadian Patent No. 1,187,914 issued May 28, 1985 discloses and claims (inter alia) an antiphoto-copying paper which has substantial advantages over the prior art. The antiphotocopying paper which is the subject of Canadian Patent No. 1,187,914 has a colour with a reflection spectral response of less than about 10~ for light with a wavelength below about 600 millimicrons and yet which is sufficiently visually contrasting with in-formation, when the information is typed thereon or other-wise applied thereto, to enable the information to be read by the human eye when the paper is viewed under white light.
We have now discovered an even more improved manner - 1 - ~
, ~ .
~L21~&~?5 of rendering documents resistant to photocopying.
In accordance with this further invention, a docu-ment has information appearing thereon with at least a portion of the information being located on a front face of the por-tion of the document, and the front face portion has a colour with a sufficiently low reflection spectral response to render the document portion substantially incapable of being photo-copied in an information-readable manner, that is to say with the information having a similar low reflection spectral res-ponse, and said document portion being capable of transmittingvisible light from the rear face to the front face to cause sufficient contrast between the relatively non-translucent information and the transmitted light to enable the informa-tion to be read by a human eye viewing the front face of the document when visible light is transmitted through the docu-ment from the rear face to the front face thereof.
The reflection spectral response is advantageously substantially zero for light with a wavelength below about 625 millimicrons, preferably substantially zero for light with a wavelength below about 650 millimicrons, and more prefer-ably substantially zero for light with a wavelength below about 700 millimicrons.
The portion of the document carrying information which is not to be photocopied preferably has a transmission factor averaging 3~ in the visible light range. Advantageously, the transmission factor ranges from substantially zero for light with a wavelength of about 450 millimicrons to about 5%
for light with a wavelength of about 700 millimicrons. Usually, the information will be in a substantially black relatively non-translucent colour.
~L21~80~
Thus, in accordance with the present invention, the document is particularly resistant to photocopying since photocopiers require the document to have an adequate reflec-tion spectral response for light of wavelengths to which the photocopier responds. Most photocopiers do not respond to light with a wavelength above about 625 millimicrons, and are most unlikely to respond to light with a wavelength above about 650 millimicrons. A document in accordance with the present invention therefore is very effectively resistant to photocopying.
On the other hand, a document in accordance with the present invention can be very easily read by means of visible light transmitted through the document from the rear. The visible light may simply be daylight or other ambient light or may be a light which is specifically intended for reading a document in accordance with the present invention. The low reflection spectral response may be provided by applying a suitable ink to a suitable paper or by applying a sui-table pre-manufactured colour film to a suitable paper.
One embodiment of the present invention will now be described by way of example, with reference to the accompany-ing drawings, of which:
Figure 1 is a graph showing the reflection spectral response and transmission factor of anti-photocopying paper in accordance with one embodiment of the invention, and also show-ing the average spectral response of the human eye and a typical spectral response of a photocopier, and Figure 2 is a graph showing the readability of ~L2~4~QS
information on the paper when viewed by means of reflec~ed incident light and by means of transmitted light.
Referring first to Figure 1, a document comprises a sheet of coloured paper having a transmission factor indi-cated by the iine T and a reflection spectral response in-dicated by the line R. Figure 1 also shows the typical spectral response of the human eye by the line E and a pos-sible spectral response of a photocopier by the line P.
It will be noted that the line P indicates that the spectral response of the photocopier decreases to zero at a wavelength of about 650 millimicrons, with a cut-off at about 625 millimicrons, the term "cut-off" being usually applied to the wavelength at which the spectral response has fallen to less than about 10~.
The transmission factor T of the paper increases substantially linearly from zero at a wavelength of about 450 millimicrons to about 5% at a wavelength of about 700 millimicrons, therefore averaging about 3% over the visible light range encompassed by the line E. Above the visible light range, the transmission factor increases substantially linearly to about 10% for light with a wavelength of about 1,000 millimicrons.
The reflection spectral response R is very low (substantially zero) below about 700 millimicronst i.e. less than about 1%, and is also of this order at wavelengths above 700 millimicrons up to about 1,000 millimicrons.
The paper may for example be that sold by Kimberley Clark Corporation under the trade mark W ULTRA II covered on the front face with matt finished "black" ink (such as produced by Cal/Ink Limited or Sinclair & Valentine Limited) to give the required transmission factor.
Information is then typed, printed or otherwise applied in black or similar dark colour on the front face of the paper so that it is relatively non-translucent. Any kind of information may of course be applied, including printed, written or drawn text, graphs or illustrations.
Frequently, the information may be applied to the paper by means of a photocopier from an original document which is not resistant to photocopying. In such a case, anti-photo-copying paper in accordance with the invention will be used as the copy paper in a photocopying machine, with the result that the information will appear on the paper as baked black carbon deposits.
If an attempt is made to photocopy the resultant document, the photocopy will be unreadable because the information on the photocopy will not be distinguishable from the background. In other words, the photocopy will show the background in the same colour as the information since the reflection spectral response of the paper is sub-stantially zero below about 700 millimicrons.
On the other hand, if the document is illustrated from behind, either by positioning the document so that ambient daylight or artificial light or special artificial light passes therethrough from behind, the information can be easily read by the human eye when viewed from the front because the black or substantially black information will be sufficiently contrasting with the background which is lightened by the transmitted light.
Figure 2 shows the relative eye response when i21~
viewing the document. Line 1 shows the eye response to view-ing by light transmitted through the paper, and line 2 shows the eye response to viewing by reflected incident light. When viewing by transmitted light, the transmitted light is easily seen in contrast to the information, particularly at wave-lengths to which the human eye is most responsive as indi-cated by line E in Figure 1. With reflected light, the eye merely perceives the paper to be substantially black and sub-stantially indistinguishable from the information.
The invention is of course applicable to any security documents, including lottery tickets, show and sports events tickets, postal and fiscal stamps, stock shares and bond certificates, credit cards, person~l and bank cheques, travellers cheques and bank notes.
Other embodiments and examples of the invention will be readily apparent to a person skilled in the art, the scope of the invention being defined in the appended claims.
Claims (30)
1. A document having information appearing thereon, with at least a portion of the information being located on a front face of a portion of the document, said front face portion having a colour with a sufficiently low reflection spectral response to render said document portion substan-tially incapable of being photocopied in an information-readable manner, and said document portion being capable of transmitting visible light from the rear face to the front face to cause sufficient contrast between the rela-tively non-translucent information and the transmitted light to enable the information to be read by a human eye viewing the front face of the document when visible light is transmitted through the document from the rear face to the front face thereof.
2. A document according to claim 1 wherein said re-flection spectral response is substantially zero for light with a wavelength below about 625 millimicrons
3. A document according to claim 1 wherein said re-flection spectral response is substantially zero for light with a wavelength below about 700 millimicrons.
4. A document according to claim 1 wherein said docu-ment portion has a transmission factor averaging about 3%
in the visible light range.
in the visible light range.
5. A document according to claim 1 wherein said docu-ment portion has a transmission factor ranging from substan-tially zero for light with a wavelength of about 450 milli-microns to about 5% for light with a wavelength of about 700 millimicrons.
6. A document according to claim 1 wherein said informa-tion is of a substantially black relatively non-translucent colour, and said reflection spectral response is substantially zero for light with a wavelength below about 625 millimicrons.
7. A document according to claim 6 wherein said document port on has a transmission factor averaging about 3% in the visible light range.
8. A document according to claim 6 wherein said reflec-tion spectral response is substantially zero for light with a wavelength below about 700 millimicrons.
9. A document according to claim 8 wherein said trans-mission factor ranges from substantially zero for light with a wavelength about 450 millimicrons to about 5% for light with a wavelength about 700 millimicrons.
10. A method of rendering a document with information thereon resistant to photocopying, said method comprising providing said information on a front face of a document having a colour with a sufficiently low reflection spectral response to render the document substantially incapable of being photocopied in an information-readable manner and which is capable of transmitting visible light from a rear face to the front face to cause sufficient contract between the rela-tively non-translucent information and the transmitted light to enable the information to be read by a human eye viewing the front face of the document when visible light is trans-mitted through the document from the rear face to the front face thereof.
11. A method according to claim 10 wherein said re-flection spectral response is substantially zero for light with a wavelength below about 625 millimicrons.
12. A method according to claim 10 wherein said re-flection spectral response is substantially zero for light with a wavelength below about 700 millimicrons.
13. A method according to claim 10 wherein said docu-ment portion has a transmission factor averaging about 3%
in the visible light range.
in the visible light range.
14. A method according to claim 10 wherein said docu-ment portion has a transmission factor ranging from substan-tially zero for light with a wavelength of about 450 milli-microns to about 5% for light with a wavelength of about 700 millimicrons.
15. A method according to claim 10 wherein said informa-tion is of a substantially black relatively non-translucent colour and said reflection spectral response is substantially zero for light with a wavelength below about 625 millimicrons.
16. A method according to claim 15 wherein said docu-ment portion has a transmission factor averaging about 3% in the visible light range.
17. A method according to claim 15 wherein said reflec-tion spectral response is substantially zero for light with a wavelength below about 700 millimicrons.
18. A method according to claim 17 wherein said trans-mission factor ranges from substantially zero for light with a wavelength about 450 millimicrons to about 5% for light with a wavelength about 700 millimicrons.
19. Anti-photocopying paper having a front face having a colour with sufficiently low reflection spectral response to render the document substantially incapable of being photocopies in an information readable manner, after informa-tion has been typed or otherwise applied to said front face, and said paper being capable of transmitting visible light from a rear face to the front face to cause sufficient contrast between the relatively non-translucent information and the transmitted light to enable the information to be read by a human eye viewing the front face of the document when visible light is transmitted through the document from the rear face to the front face thereof.
20. Paper according to claim 19 wherein said reflec-tion spectral response is substantially zero for light with a wavelength below about 625 millimicrons.
21. Paper according to claim 19 wherein said reflec-tion spectral response is substantially zero for light with a wavelength below about 700 millimicrons.
22. Paper according to claim 19 wherein said docu-ment portion has a transmission factor averaging about 3%
in the visible light range.
in the visible light range.
23. Paper according to claim 19 wherein said docu-ment portion has a transmission factor ranging from substan-tially zero for light with a wavelength of about 450 milli-microns to about 5% for light with a wavelength of about 700 millimicrons.
24. Paper according to claim 19 wherein said informa-tion is of a substantially black relatively non-translucent colour, and said reflection spectral response is substan-tially zero for light with a wavelength below about 625 millimicrons.
25. Paper according to claim 24 wherein said document portion has a transmission factor averaging about 3% in the visible light range.
26. Paper according to claim 24 wherein said reflec-tion spectral response is substantially zero for light with a wavelength below about 700 millimicrons.
27. Paper according to claim 26 wherein said trans-mission factor ranges from substantially zero for light with a wavelength about 450 millimicrons to about 5% for light with a wavelength about 700 millimicrons.
28. A document according to claim 1 wherein said reflection spectral response is substantially zero for light with a wavelength below about 1000 millimicrons.
29. A method according to claim 10 wherein said reflection spectral response is substantially zero for light with a wavelength below about 1000 millimicrons.
30. Paper according to claim 19 wherein said reflec-tion spectral response is substantially zero for light with a wavelength below about 1000 millimicrons.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US06/475,791 US4632429A (en) | 1981-05-25 | 1983-03-16 | Method of rendering documents resistant to photocopying and anti-copying paper therefor |
| US475,791 | 1983-03-16 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1214805A true CA1214805A (en) | 1986-12-02 |
Family
ID=23889168
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000434210A Expired CA1214805A (en) | 1983-03-16 | 1983-08-09 | Method of rendering documents resistant to photocopying and anti-photocopying paper therefor |
Country Status (12)
| Country | Link |
|---|---|
| EP (1) | EP0119344B1 (en) |
| JP (1) | JPS59174870A (en) |
| AT (1) | ATE32274T1 (en) |
| AU (1) | AU560208B2 (en) |
| CA (1) | CA1214805A (en) |
| DE (1) | DE3375527D1 (en) |
| DK (1) | DK243283A (en) |
| FI (1) | FI79671C (en) |
| HK (1) | HK98688A (en) |
| NO (1) | NO171099C (en) |
| NZ (1) | NZ205794A (en) |
| ZA (1) | ZA833659B (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP4951163B2 (en) * | 2008-07-03 | 2012-06-13 | 美津濃株式会社 | Sports gloves |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3852088A (en) * | 1972-03-20 | 1974-12-03 | Ibm | Security document system and method |
| US3887742A (en) * | 1972-04-13 | 1975-06-03 | Richard E Reinnagel | Copy resistant documents |
| FR2247067A5 (en) * | 1973-10-04 | 1975-05-02 | Arjomari Prioux | Non-photocopiable security document - allows markings to be read by eye but reflects uniform light when illuminated |
| JPS55100587A (en) * | 1979-01-29 | 1980-07-31 | Toppan Printing Co Ltd | Image forming material |
| GB2096055B (en) * | 1979-09-17 | 1985-02-27 | Auken John A Van | Anti-copying systems for copying machines |
-
1983
- 1983-05-20 ZA ZA833659A patent/ZA833659B/en unknown
- 1983-05-26 FI FI831891A patent/FI79671C/en not_active IP Right Cessation
- 1983-05-27 NO NO831896A patent/NO171099C/en unknown
- 1983-05-30 DK DK243283A patent/DK243283A/en not_active Application Discontinuation
- 1983-08-09 CA CA000434210A patent/CA1214805A/en not_active Expired
- 1983-08-17 DE DE8383304762T patent/DE3375527D1/en not_active Expired
- 1983-08-17 AT AT83304762T patent/ATE32274T1/en not_active IP Right Cessation
- 1983-08-17 EP EP83304762A patent/EP0119344B1/en not_active Expired
- 1983-08-18 AU AU18110/83A patent/AU560208B2/en not_active Ceased
- 1983-08-22 JP JP58151755A patent/JPS59174870A/en active Granted
- 1983-09-28 NZ NZ205794A patent/NZ205794A/en unknown
-
1988
- 1988-12-08 HK HK986/88A patent/HK98688A/en not_active IP Right Cessation
Also Published As
| Publication number | Publication date |
|---|---|
| AU560208B2 (en) | 1987-04-02 |
| DK243283D0 (en) | 1983-05-30 |
| EP0119344B1 (en) | 1988-01-27 |
| NZ205794A (en) | 1987-02-20 |
| DK243283A (en) | 1984-09-17 |
| FI831891L (en) | 1984-09-17 |
| ATE32274T1 (en) | 1988-02-15 |
| FI79671B (en) | 1989-10-31 |
| JPH0513318B2 (en) | 1993-02-22 |
| JPS59174870A (en) | 1984-10-03 |
| HK98688A (en) | 1988-12-16 |
| EP0119344A1 (en) | 1984-09-26 |
| AU1811083A (en) | 1984-09-20 |
| NO171099C (en) | 1993-01-27 |
| FI831891A0 (en) | 1983-05-26 |
| FI79671C (en) | 1990-02-12 |
| NO831896L (en) | 1984-09-17 |
| DE3375527D1 (en) | 1988-03-03 |
| NO171099B (en) | 1992-10-19 |
| ZA833659B (en) | 1984-10-31 |
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