Refrigerated display case having a transparent insulating glazing unit

• US 7,976,916 B2
• Filed: 05/26/2005
• Issued: 07/12/2011
• Est. Priority Date: 05/25/1999
• Status: Expired due to Fees

• Current Assignee: Saint-Gobain Glass France (Compagnie De Saint-Gobain)
• Original Assignee: Saint-Gobain Vitrage
• Inventors: Hebert, Anne-Sophie, Grussaute Nghiem, Hélène, Florentin, Jean-Michel, Riblier, Luc-Michel, Messere, Rino
• Primary Examiner(s): Dye; Rena L
• Assistant Examiner(s): YAGER, JAMES C
• Application Number:
  US11/137,373
• Publication Number:
  US 20060005484A1
• Time in Patent Office: 2,238 Days
• Field of Search: 428/34.1, 428/34.7
• US Class Current: 428/34.7
• CPC Class Codes: A47F 3/0434 Glass or transparent panels
• CPC Class Codes: E06B 3/677 Evacuating or filling the gap between the panes ; Equilibration of inside and outside pressure; Preventing condensation in the gap between the panes by means of spacing elements E06B3/663; Cleaning the gap between the panes
• CPC Class Codes: Y10T 428/13 Hollow or container type article [e.g., tube, vase, etc.]
• CPC Class Codes: Y10T 428/1321 Polymer or resin containing [i.e., natural or synthetic]

Abstract

A refrigerated display case having a transparent insulating glazing unit for displaying cold or frozen products. The glazing unit has an antifrosting absorbent layer that inhibits the formation of visible condensation or frost.

Claims

1. A refrigerated display case comprising:

a refrigerated enclosure constructed and arranged to contain cold or frozen products;

a door constructed and arranged to seal the refrigerated enclosure when in a closed position, the door having a transparent insulating glazing unit comprising at least two glass substrates; and

an antifrosting adsorbent layer disposed on a surface of a glass substrate facing an interior of the refrigerated enclosure and formed from at least one hydrophilic polymer, wherein the transparent insulating glazing unit inhibits the formation of condensation on a surface of the glass substrate in contact with the ambient atmosphere and the antifrosting adsorbent layer inhibits the formation of water crystals on the surface of the glass substrate facing the interior of the refrigerated enclosure when the door is opened, wherein the hydrophilic polymer is combined with an organic or inorganic absorbent material.

2. A refrigerated display case according to claim 1, wherein the hydrophilic polymer is crosslinked.

3. A refrigerated display case according to claim 1, wherein the hydrophilic polymer is selected from the group consisting of a polyvinylpyrrolidone of a poly(N-vinyl-2-pyrrolidone) or poly(1-vinylpyrrolidone) polymer, a polyvinylpyridine of a poly(N-vinyl-2-pyridine) polymer, of a poly(N-vinyl-3-pyridine) polymer or of a poly(N-vinyl-4-pyridine) polymer, a polyacrylate of a poly(2-hydroxyethyl acrylate) polymer, a polyacrylamide of a poly(N′

,N-hydroxyacrylamide) polymer, a polyvinyl acetate, a polyacrylonitrile, a polyvinyl alcohol, a polyacrolein, a polyethylene glycol or a polyoxyethylene, and copolymers based on two or more of the polymers listed.

4. A refrigerated display case according to claim 1, wherein the hydrophilic polymer combined with an organic or inorganic absorbent material forms a polymeric porous three-dimensional network.

5. A refrigerated display case according to claim 4, wherein the hydrophilic polymer combined with an organic or inorganic absorbent material comprises polyvinylpyrrolidone and polyurethane.

6. A refrigerated display case according to claim 1, wherein the absorbent material is porous.

7. A display case according to claim 6, wherein the porous absorbent material has a porosity of between 0.1 and 1000 cm³/g, and a mean diameter of pores between 0.05 and 50 microns.

8. A refrigerated display case according to claim 7, wherein the porous absorbent material has porosity between 200 and 1000 cm³/g when the material is a mesoporous.

9. A refrigerated display case according to claim 6, wherein the porous absorbent material comprises at least one material selected from the group consisting of mesoporous materials, orthosilicate hydrolysis condensation products, and silicon derivatives.

10. A refrigerated display case according to claim 6, wherein the porous absorbent material is a polymeric material.

11. A refrigerated display case according to claim 6, wherein the porous absorbent material has porosity between 0.1 and 100 cm³/g when the material is a polymeric material.

12. A refrigerated display case according to claim 11, wherein the porous absorbent material has porosity between 0.1 and 20 cm³/g.

13. A refrigerated display case according to claim 1, wherein the transparent insulating glazing unit comprises two glass substrates having a vacuum between the two glass substrates.

14. A refrigerated display case according to claim 1, wherein the thickness of the antifrosting adsorbent layer is less than 100 microns.

15. A refrigerated display case according to claim 1, wherein the thickness of the antifrosting adsorbent layer is less than 50 microns.

16. A refrigerated display case according to claim 1, wherein the thickness of the antifrosting adsorbent layer is less than 35 microns.

17. A refrigerated display case according to claim 1, wherein the thickness of the antifrosting adsorbent layer is less than 25 microns.

18. A refrigerated display case according to claim 1, wherein the thickness of the antifrosting adsorbent layer is less than 20 microns.

19. A refrigerated display case according to claim 7, wherein the mean diameter of the pores of the absorbent material is between 0.1 and 20 microns.

20. A refrigerated display case according to claim 7, wherein the mean diameter of the pores of the absorbent material is between 1 and 15 microns.

21. A refrigerated display case according to claim 1, wherein the antifrosting adsorbent layer is disposed on one side a polycarbonate film and another side of the polycarbonate film is bonded to the glass substrate.

22. A refrigerated display case according to claim 1, wherein the insulating glazing unit and antifrosting coating are constructed and arranged such that when a temperature of −

28°

C. is maintained within the refrigerated enclosure and an ambient temperature is 25°

C. no visible frost or condensation forms after 12 seconds of the door being in an open position.

23. A refrigerated display case according to claim 1, wherein the insulating glazing unit comprises three glass substrates.

24. A refrigerated display case according to claim 1, further comprising a low-emission coating disposed on at least one surface of said glass substrates.

25. A refrigerated display case according to claim 23, further comprising a low-emission coating disposed on at least one surface of said glass substrates.

26. A refrigerated display case according to claim 24, further comprising at least one gas disposed between the glass substrates, said gas being selected from the group consisting of argon, krypton and xenon.

27. A refrigerated display case according to claim 25, further comprising at least one gas disposed between at least two of the glass substrates, said gas being selected from the group consisting of argon, krypton and xenon.

28. A refrigerated display case according to claim 26, the insulating glazing unit has a thermal conductivity coefficient U of less than 1.15 W/m².K, with at least 85% of said gas filling, a light transmission ratio of at least 75% and an external light reflection factor of below 12%.

29. A refrigerated display case according to claim 27, the insulating glazing unit has a thermal conductivity coefficient U of less than 1.1 W/m².K, with at least 85% of said gas filling, a light transmission ratio of at least 67% and a light reflection factor of below 18%.

30. A refrigerated display case according to claim 1, further comprising a spacer disposed between the glass substrates, the spacer comprising a first sealing barrier comprising a body made of thermoplastic polymer mixed with reinforcing fibres and a metal sheet at least partly covering the thermoplastic polymer, and a second sealing barrier against liquids and vapour.

31. A refrigerated display case according to claim 1, further comprising a spacer secured to the edges of the substrates, the spacer constituting also a sealing barrier against gases, dust and liquids.

33. A refrigerated display case according to claim 1, wherein the insulating glazing unit has no heating element.

32. A refrigerated display case comprising:

a refrigerated enclosure constructed and arranged to contain cold or frozen products;

a door constructed and arranged to seal the refrigerated enclosure when in a closed position, the door having a transparent insulating glazing unit comprising at least two glass substrates; and

an antifrosting adsorbent layer disposed on a surface of a glass substrate facing an interior of the refrigerated enclosure, the antifrosting adsorbent layer being further an absorbent layer which is porous to allow condensation to absorb therein, wherein the transparent insulating glazing unit inhibits the formation of condensation on a surface of the glass substrate in contact with the ambient atmosphere and the antifrosting adsorbent layer inhibits the formation of water crystals on the surface of the glass substrate facing the interior of the refrigerated enclosure when the door is opened.