Process for embossing a relief pattern into a thermoplastic information carrier

• US 4,223,050 A
• Filed: 10/03/1978
• Issued: 09/16/1980
• Est. Priority Date: 05/04/1976
• Status: Expired due to Term

• Current Assignee: LGZ Landis & Gyr Zug AG (Landis+Gyr Group AG)
• Original Assignee: LGZ Landis & Gyr Zug AG (Landis+Gyr Group AG)
• Inventors: Greenaway, David L., Nyfeler, Alex
• Primary Examiner(s): Lowe, James B.
• Application Number:
  US05/948,239
• Time in Patent Office: 714 Days
• Field of Search: 264/1, 264/2, 264/25, 264/284, 264/293, 264/134, 427/162, 427/163, 427/276, 427/277
• US Class Current: 427/163.1
• CPC Class Codes: B29C 2035/0211 resistance heating B29C2035/0811 takes precedence
• CPC Class Codes: B29C 59/02 by mechanical means, e.g. pressing B29C59/007 takes precedence; embossing expanded porous articles B29C44/5627
• CPC Class Codes: B41C 3/00 Reproduction or duplicating of printing formes
• CPC Class Codes: B41C 3/06 to produce printing blocks from plastics
• CPC Class Codes: G03G 5/022 Layers for surface-deformation imaging, e.g. frost imaging
• CPC Class Codes: G03H 1/0244 Surface relief holograms replicating hologram without interference recording G03H1/0276
• CPC Class Codes: G03H 1/028 by embossing
• CPC Class Codes: G03H 1/0476 Holographic printer G03H1/268 takes precedence
• CPC Class Codes: G06K 1/126 by photographic or thermographic registration recording apparatus for measuring instruments G01D15/00
• CPC Class Codes: G06K 1/128 by electric registration, e.g. electrolytic, spark erosion recording apparatus for measuring instruments G01D15/06; information storage in general G11
• CPC Class Codes: G06K 19/16 the marking being a hologram or diffraction grating
• CPC Class Codes: G07B 5/06 for preventing fraudulent operation
• CPC Class Codes: G11B 11/00 Recording on or reproducing from the same record carrier wherein for these two operations the methods are covered by different main groups of groups G11B3/00 - G11B7/00 or by different subgroups of group G11B9/00; Record carriers therefor driving or moving of heads G11B3/02, G11B5/48, G11B7/08, G11B21/02

Abstract

There is disclosed a method for embossing a relief pattern of high resolution into a thermoplastic information carrier by means of a heatable embossing matrix. The matrix, which exhibits the desired relief pattern, is pressed onto the thermoplastic information carrier, and is then heated by means of an electric current. After the electric current has ceased, the embossing pressure is maintained until the thermoplastic information carrier has hardened through cooling. Alternative methods permits selected variation of the relief pattern to be embossed by selectively altering the surface of the support member which supports the information carrier during the embossing operation or by selectively heating the embossing matrix.

Claims

1. A method for embossing a selected high-resolution diffraction phase relief pattern representing coded information into a thermoplastic information carrier, comprising:

placing the thermoplastic information carrier on a support member;

pressing a foil-shaped embossing matrix onto the thermoplastic information carrier, said embossing matrix having a diffraction phase relief pattern on the surface which is pressed onto the thermoplastic information carrier, and comprising a plurality of band-shaped branches each having a portion of said relief pattern contained thereon;

selectively heating the embossing matrix by passing an electric current impulse through selected said branches of said matrix while it is pressed onto the thermoplastic information carrier, to cause the portions of the relief pattern contained on said branches to be embossed into the thermoplastic information carrier; and

maintaining the embossing matrix pressed onto the thermoplastic information carrier after the electric current impulse has ceased, until the selected embossed relief pattern formed on the thermoplastic information carrier has hardened.

2. A method according to claim 1, wherein the thermoplastic information carrier has a coating of a thin metallic layer, and the selected relief pattern is embossed into the information carrier through said layer.

3. A method according to claim 1, wherein the selected relief pattern is a phase hologram or a phase diffraction grating.

4. A method for embossing a selected high-resolution diffraction phase relief pattern representing coded information into a thermoplastic information carrier, comprising:

placing the thermoplastic information carrier on a support member, said support member comprising a base plate having an essentially planar surface facing the thermoplastic information carrier, said surface having a plurality of recesses formed therein, said support member further comprising a plurality of movable sliding sections, each sliding section being movably mounted in one of the recesses in said support member for movement between a rest position and a depressed position, each sliding section having its uppermost surface in coplanar relationship to said surface of the base plate when the sliding section is in the rest position, and in a lowered, non-coplanar relationship when the sliding section is in the depressed position;

selectively altering the surface area of said support member by moving each of said sliding sections into either the rest position or the depressed position so that said thermoplastic information carrier is supported only by selected portions of said support member;

pressing a foil-shaped embossing matrix onto the thermoplastic information carrier;

said embossing matrix having a diffraction phase relief pattern on the surface which is pressed onto the thermoplastic information carrier;

heating the embossing matrix by passing an electric current impulse through said matrix while it is pressed onto the thermoplastic information carrier; and

maintaining the embossing matrix presssed onto the thermoplastic information carrier after the electric current impulse has ceased, until the selected embossed relief pattern formed on the thermoplastic information carrier has hardened.

5. A method according to claim 4, wherein said selected relief pattern is a phase hologram or a phase diffraction grating.

6. A method according to claim 4, wherein the thermoplastic information carrier has a coating of a thin metallic layer, and the selected relief pattern is embossed into the information carrier through said layer.

7. A method for embossing a high-resolution diffraction phase relief pattern into a thermoplastic information carrier, comprising:

coating the thermoplastic information carrier with a thin metallic layer;

placing the coated thermoplastic information carrier on a support member;

pressing a foil-shaped embossing matrix onto the coated thermoplastic information carrier by means of a punch, said embossing matrix having a diffraction phase relief pattern on the surface which is pressed onto the coated thermoplastic information carrier;

heating the embossing matrix by passing an electric current impulse through said matrix while it is pressed onto the coated thermoplastic information carrier; and

maintaining the embossing matrix pressed onto the coated thermoplastic information carrier after the electric current has ceased, until the relief pattern embossed through said metallic layer in said thermoplastic information carrier has hardened.

8. A method according to claim 7, wherein the embossed relief pattern is a phase hologram or a phase diffraction grating.

9. A method according to claim 7, wherein the distance between the lines of the relief pattern is a few microns or less.