JPS5699358A - Tape for preventing document from copying - Google Patents

Tape for preventing document from copying

Info

Publication number
JPS5699358A
JPS5699358A JP239280A JP239280A JPS5699358A JP S5699358 A JPS5699358 A JP S5699358A JP 239280 A JP239280 A JP 239280A JP 239280 A JP239280 A JP 239280A JP S5699358 A JPS5699358 A JP S5699358A
Authority
JP
Japan
Prior art keywords
tape
layer
copying
refractive index
difference
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.)
Granted
Application number
JP239280A
Other languages
Japanese (ja)
Other versions
JPS6311671B2 (en
Inventor
Yohei Ikezu
Shuichi Karasawa
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Ricoh Co Ltd
Original Assignee
Ricoh Co Ltd
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Ricoh Co Ltd filed Critical Ricoh Co Ltd
Priority to JP239280A priority Critical patent/JPS5699358A/en
Publication of JPS5699358A publication Critical patent/JPS5699358A/en
Publication of JPS6311671B2 publication Critical patent/JPS6311671B2/ja
Granted legal-status Critical Current

Links

Landscapes

  • Exposure Or Original Feeding In Electrophotography (AREA)

Abstract

PURPOSE:To perfectly prevent secret documents from copying without hindrance in observing them directly with naked eyes, by applying a tape with a glass bead layer formed to the whole surface of them or a part of them. CONSTITUTION:Copy preventing tape 1 is wounded around proper reel 2, and a necessary length of tape 1, when needed, is drawn out and applied to the secret document copying of which has to be prevented. The second transparent adhesive layer 7 is formed to stick glass bead layer 6 onto transparent base 5. Glass beads (b) of layer 6 have 60mum mean sphere diameter and >=1.9 refractive index, and the greater the difference of refractive index between layer 7 and beads (b), the better, and it is preferable that the difference is approximate to 1.0 as closely as possible.
JP239280A 1980-01-12 1980-01-12 Tape for preventing document from copying Granted JPS5699358A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP239280A JPS5699358A (en) 1980-01-12 1980-01-12 Tape for preventing document from copying

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP239280A JPS5699358A (en) 1980-01-12 1980-01-12 Tape for preventing document from copying

Publications (2)

Publication Number Publication Date
JPS5699358A true JPS5699358A (en) 1981-08-10
JPS6311671B2 JPS6311671B2 (en) 1988-03-15

Family

ID=11527956

Family Applications (1)

Application Number Title Priority Date Filing Date
JP239280A Granted JPS5699358A (en) 1980-01-12 1980-01-12 Tape for preventing document from copying

Country Status (1)

Country Link
JP (1) JPS5699358A (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS58138670U (en) * 1982-03-12 1983-09-17 凸版印刷株式会社 Copy protection documents
JPH07172035A (en) * 1994-06-24 1995-07-11 Dainippon Printing Co Ltd Copy preventive medium
JPH08339138A (en) * 1996-06-25 1996-12-24 Dainippon Printing Co Ltd Copy-preventing medium

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS58138670U (en) * 1982-03-12 1983-09-17 凸版印刷株式会社 Copy protection documents
JPH0213178Y2 (en) * 1982-03-12 1990-04-12
JPH07172035A (en) * 1994-06-24 1995-07-11 Dainippon Printing Co Ltd Copy preventive medium
JPH08339138A (en) * 1996-06-25 1996-12-24 Dainippon Printing Co Ltd Copy-preventing medium

Also Published As

Publication number Publication date
JPS6311671B2 (en) 1988-03-15

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