Mask exposure method, transparent conductive metallization and pigment

Patent metadata

Field	Value
Publication number	US-12128704-B2
Application number	US-202218263787-A
Country	US
Kind code	B2
Filing date	Jan 10, 2022
Priority date	Feb 1, 2021
Publication date	Oct 29, 2024
Grant date	Oct 29, 2024

Abstract

The invention relates to a mask exposure method comprising the following steps: —the providing of a carrier substrate; the print application of a radiation-crosslinkable washable dye layer to the full area of the carrier substrate; —the exposure of the radiation-crosslinkable washable dye layer in defined regions to radiation by means of a radiation mask, such that the washable dye is cured in the defined regions; —the applying of a metallization over the full area; —the removing of the non-radiation-exposed washable dye outside the defined regions together with the metal present thereon with the aid of a solvent, such that the resultant carrier substrate has cured washable dye with metal applied thereto only in defined regions.

First claim

The invention claimed is:

1. A mask exposure method, comprising the following steps:
providing a carrier substrate;
applying a full-area, radiation-crosslinkable, washable ink layer to the carrier substrate;
irradiating the radiation-crosslinkable, washable ink layer in defined regions by means of a shadow mask, so that washable ink is cured in the defined regions;
applying a full-area metallization;
removing non-irradiated washable ink outside of the defined regions, together with metal present thereon, by means of a solvent, so that the carrier substrate obtained comprises cured washable ink with metal applied thereon only in the defined regions.

2. The mask exposure method according to claim 1 , wherein the carrier substrate obtained which only in defined regions comprises cured washable ink with metal applied thereon forms a transparent, conductive metallization in the form of a periodic, coherent network.

3. The mask exposure method according to claim 2 , wherein the shadow mask comprises a radiation-transparent material which in defined regions comprises a material impervious to the radiation; wherein a geometry of the metallization generated in the method, in the form of a periodic, coherent network, is determined by choice of parameters of a geometric structure of the radiation-impervious shadow mask material and of spacing of the radiation-impervious shadow mask material.

4. A transparent, conductive metallization in the form of a periodic, coherent network, obtainable by the method according to claim 2 .

5. The mask exposure method according to claim 1 , wherein the shadow mask comprises a radiation-transparent material which in defined regions comprises a material impervious to the radiation.

6. The mask exposure method according to claim 5 , wherein the shadow mask has a cylindrical shape, and the radiation-transparent material comprises glass or quartz.

7. The mask exposure method according to claim 6 , wherein the step of irradiating the radiation-crosslinkable, washable ink layer in defined regions by means of the cylindrical shadow mask, so that the washable ink is cured in the defined regions, is carried out such that a web speed of the carrier substrate, present in the form of a substrate web, coincides with a rotary speed of the cylindrical shadow mask.

8. The mask exposure method according to claim 1 , wherein the radiation-crosslinkable, washable ink layer comprises a composition which comprises a photoinitiator and a binder.

9. The mask exposure method according to claim 8 , wherein the binder is a polymer selected from the group consisting of hydroxyethylcellulose, hydroxypropylcellulose, carboxymethylcellulose, polyvinyl alcohol, polyvinylpyrrolidone, polyethylene glycol and casein.

10. The mask exposure method according to claim 8 , wherein the composition of the radiation-crosslinkable, washable ink layer further comprises a reactive diluent.

11. The mask exposure method according to claim 1 , wherein after the step of the removal of the non-irradiated washable ink outside of the defined regions, together with the metal present thereon, by means of a solvent, the step of isolation of the metal removed takes place, in order thus to obtain platelet-shaped pigments.

12. A platelet-shaped pigment obtainable by the method according to claim 11 .

Assignees

• Giesecke & Devrient Currency Technology Gmbh

Inventors

• Hoffmuller Winfried
• Sobol Michael
• Rauch Andreas

Classifications

• B42D25/445

  using chemical means, e.g. etching · CPC title

• B42D25/373 Primary

  Metallic materials · CPC title

• H10K71/621

  Providing a shape to conductive layers, e.g. patterning or selective deposition · CPC title

• B42D25/41 Primary

  using electromagnetic radiation (B42D25/435 takes precedence) · CPC title