Night Vision Light Filter

• US 20070273057A1
• Filed: 03/07/2005
• Published: 11/29/2007
• Est. Priority Date: 04/09/2004
• Status: Abandoned Application

• Current Assignee: 45, RUE DE VILLIERS
• Original Assignee: 45, RUE DE VILLIERS
• Inventors: Divay, Laurent, Le Barny, Pierre, Francoise, Soyer
• Application Number:
  US11/547,781
• Publication Number:
  US 20070273057A1
• Time in Patent Office: Days
• US Class Current: 264/1.380
• CPC Class Codes: C08F 2/44 Polymerisation in the presence of compounding ingredients, e.g. plasticisers, dyestuffs, fillers
• CPC Class Codes: C08F 2/50 with sensitising agents
• CPC Class Codes: C08F 222/1025 of aromatic dialcohols
• CPC Class Codes: G02B 23/12 with means for image conversion or intensification
• CPC Class Codes: G02B 5/208 for use with infrared or ultraviolet radiation, e.g. for separating visible light from infrared and/or ultraviolet radiation

Abstract

Process for the manufacture of a light filter compatible with night vision goggles having at least the following stages: preparation of a homogeneous solution comprising one monomer, one dye; one photoinitiator; photochemical crosslinking by ultraviolet radiation of the solution in the film form; annealing the photocrosslinked film.

Claims

1. A process for the manufacture of a light filter compatible with night vision goggles comprising:

preparation of a homogeneous solution (S) including

one monomer;

one dye;

one photoinitiator;

photochemical crosslinking by ultraviolet radiation of the solution in the film form;

annealing the photocrosslinked film.

15. The process for the manufacture of a filter as claimed in claim 1, wherein the monomer is chosen from the family (A) of the diacrylates with the following chemical structure:

R₁ being;

either CH₃ or H;

R₂ being;

(CH₂-CH₂—

O)_n;

R₃ being;

either CH₃ or H or CF₃;

R₄ being;

either CH₃ or H or CF₃;

n being an integer between 1 and 5

16. The process for the manufacture of a filter as claimed in claim 1, wherein the monomer is chosen from the family (B) of the diacrylates with the following chemical structure:

17. The process for the manufacture of a filter as claimed in claim 1, wherein the solution comprises monomers from different families.

18. The process for the manufacture of a filter as claimed in claim 17, wherein the amount of monomers from the two families is substantially identical.

19. The process for the manufacture of a filter as claimed in claim 1, wherein it is carried out by photocrosslinking a solution comprising:

a diacrylate, bisphenol A ethoxylate (1 EO/phenol) diacrylate;

two dyes, namely copper perchlorophthalocyanine and Epolight;

a photoinitiator, added to the solution in order to initiate the photocrosslinking.

20. The process for the manufacture of a filter as claimed in claim 19, wherein the bisphenol A ethoxylate (1 EO/phenol) diacrylate is a liquid difunctional monomer, the chemical structure (C) of which is represented below:

with M_n=424 g.mol<sup>−

1</sup>.

21. The process for the manufacture of a filter as claimed in claim 19, wherein the copper perchlorophthalocyanine is that which is provided in the form of a suspension in a relatively nonvolatile solvent.

22. The process for the manufacture of a filter as claimed in claim 19, wherein Epolight is a powder.

23. The process for the manufacture of a filter as claimed in claim 19, wherein the chemical structure of Darocure is:

24. The process for the manufacture of a filter as claimed in claim 18, wherein it comprises at least the following stages:

first stage;

preparation of a solution for producing a film with a thickness of 1 mm;

22.5 mg of Epolight 2057;

80 mg of a relatively nonvolatile solvent;

900 mg of photoinitiator;

g of bisphenol A ethoxylate (1 EO/phenol) diacrylate;

the solution being stirred using a magnetic bar until a homogeneous mixture is obtained;

second stage;

introduction of the solution by capillary action between two parallel glass slides (V1, V2) 1 mm apart;

third stage;

photochemical crosslinking by irradiation of the solution between the two glass sheets for 50 min with radiation emitted by two fluorescent tubes.

25. The process for the manufacture of a filter as claimed in claim 1, wherein the irradiation device comprises two rows of fluorescent tubes respectively positioned according to two parallel planes separated by a distance of 8 cm, the solution between the two glass sheets being positioned at an equal distance from the parallel planes and substantially towards the middle of the fluorescent tubes.

26. The process for the manufacture of a filter as claimed in claim 1, wherein the source of radiation is a lamp, the irradiation device comprising a support having an irradiation face supporting the glass sheets comprising the solution to be irradiated, the radiation being directed towards the irradiation face.

27. The process for the manufacture of a filter as claimed in claim 1, wherein, in a final stage which completes the process for the manufacture of the filter, the film resulting from the irradiation is heated at a temperature of 70°

C. for twelve hours.

2-14. -14. (canceled)