Merchandisers having anti-fog coatings and methods for making the same
View Patent ↗A variety of refrigerators and merchandisers having glass or plastic substrates that are substantially fog-resistant are provided. For example, refrigerator doors having a substantially transparent substrate including an anti-fog coating on at least a portion thereof are provided. The portion of the substrate may substantially not fog when the portion has an initial surface temperature and is then exposed to a moist air ambient with a dewpoint temperature equal to or greater than the surface temperature for a period of time. The surface temperature may be less than about 0° C. and the period of time may be greater than about 6 seconds.
1. A refrigerator door comprising:
a substantially transparent substrate having an anti-fog coating on at least a portion thereof, the portion of the substrate substantially not fogging when the portion has an initial surface temperature and is then exposed to a moist air ambient with a dewpoint temperature equal to or greater than the surface temperature for a period of time, wherein the surface temperature is less than about 0° C. and the period of time is greater than about 6 seconds.
2. The refrigerator door of claim 1 , wherein the period of time is greater than about 10 seconds.
3. The refrigerator door of claim 1 , wherein the period of time is greater than about 30 seconds.
4. The refrigerator door of claim 1 , wherein the period of time is greater than about one minute.
5. The refrigerator door of claim 1 , wherein the period of time is greater than about five minutes.
6. The refrigerator door of claim 1 , wherein the period of time is greater than about fifteen minutes.
7. The refrigerator door of claim 1 , wherein the surface temperature is less than about −5° C.
8. The refrigerator door of claim 7 , wherein the period of time is greater than about ten seconds.
9. The refrigerator door of claim 7 , wherein the period of time is greater than about thirty seconds.
10. The refrigerator door of claim 7 , wherein the period of time is greater than about one minute.
11. The refrigerator door of claim 7 , wherein the period of time is greater than about five minutes.
12. The refrigerator door of claim 1 , wherein the initial surface temperature is less than about −10° C.
13. The refrigerator door of claim 12 , wherein the period of time is greater than about ten seconds.
14. The refrigerator door of claim 12 , wherein the period of time is greater than about thirty seconds.
15. The refrigerator door of claim 12 , wherein the period of time is greater than about one minute.
16. The refrigerator door of claim 12 , wherein the period of time is greater than about five minutes.
17. The refrigerator door of claim 1 , wherein the initial surface temperature is less than about −15° C.
18. The refrigerator door of claim 17 , wherein the period of time is greater than about ten seconds.
19. The refrigerator door of claim 17 , wherein the period of time is greater than about thirty seconds.
20. The refrigerator door of claim 17 , wherein the period of time is greater than about one minute.
21. The refrigerator door of claim 17 , wherein the period of time is greater than about five minutes.
22. The refrigerator door of claim 1 , wherein the initial surface temperature is less than about −18° C.
23. The refrigerator door of claim 22 , wherein the period of time is greater than about 10 seconds.
24. The refrigerator door of claim 22 , wherein the period of time is greater than about 30 seconds.
25. The refrigerator door of claim 22 , wherein the period of time is greater than about one minute.
26. The refrigerator door of claim 22 , wherein the period of time is greater than about five minutes.
27. The refrigerator door of claim 22 , wherein the period of time is greater than about fifteen minutes.
28. The refrigerator door of claim 1 , wherein the coating comprises a hydrophobic surface having a surface tension and a hydrophilic interior having a hydrophilicity.
29. The refrigerator door of claim 28 , wherein the surface tension of the hydrophobic surface is less than about 30 dynes/cm.
30. The refrigerator door of claim 29 , wherein the surface tension of the surface is less than about 20 dynes/cm.
31. The refrigerator door of claim 28 , wherein the hydrophilicity is between about 20% weight gain and about 150% weight gain when the coating is immersed in water for about 96 hours at about 20 to about 25° C.
32. The refrigerator door of claim 1 , wherein the coating has a taber haze of less than about 10% at 100 cycles with 500 gram load and a CS-10F load using ASTM D 4060 testing.
33. The refrigerator door of claim 1 , wherein the coating comprises a polyurethane.
34. The refrigerator door of claim 1 , wherein the coating is substantially free of chain extenders.
35. The refrigerator door of claim 1 , wherein the refrigerator door further comprises an additional substrate having a low-emissivity surface or low-emissivity coating thereon.
36. The refrigerator door of claim 35 , wherein the low-emissivity surface or coating does not emit radiation above about 0.7 microns.
37. The refrigerator door of claim 35 , wherein the low-emissivity surface or coating does not emit radiation between about 0.7 microns and about 2.7 microns.
38. The refrigerator door of claim 35 , wherein the low-emissivity surface or coating has a visible transmittance of about 70% to about 90%.
39. The refrigerator door of claim 1 , wherein the coating exhibits less than about 0.5% detective haze by hazemeter.
40. The refrigerator door of claim 1 , wherein the life of the coating is greater than about two years.
41. The refrigerator door of claim 40 , wherein the life of the coating is greater than about 5 years.
42. The refrigerator door of claim 1 , wherein the coating is substantially free of surfactants.
43. A refrigerator door comprising a substantially transparent substrate having an anti-fog coating on at least a portion thereof, the coating comprising a polyurethane and having a surface tension of less than about 60 dynes/cm.
44. The refrigerator door of claim 43 , wherein the surface tension is less than about 30 dynes/cm.
45. The refrigerator door of claim 43 , wherein the surface tension is less than about 25 dynes/cm.
46. The refrigerator door of claim 43 , wherein the surface tension is less than about 20 dynes/cm.
47. The refrigerator door of claim 43 , wherein the coating has an exterior portion that is hydrophobic and an interior portion that is hydrophilic.
48. The refrigerator door of claim 47 , wherein the hydrophilic portion gains between about 20% weight and about 150% weight when the coating is immersed in water for about 96 hours at about 20° to about 25° C.
49. The refrigerator door of claim 47 , wherein the hydrophilic portion gains between about 30% weight and about 140% weight when the coating is immersed in water for about 96 hours at about 20° to about 25° C.
50. The refrigerator door of claim 47 , wherein the hydrophilic portion is between about 35% weight and about 110% weight when the coating is immersed in water for about 96 hours at about 20° to about 25° C.
51. The refrigerator door of claim 43 , wherein the coating has a taber haze of less than about 10% at 100 cycles with 500 gram load and a CS-10F load using ASTM D 4060 testing.
52. The refrigerator door of claim 43 , wherein the coating has a taber haze of less than about 5% at 100 cycles with 500 gram load and a CS-10F load using ASTM D 4060 testing.
53. The refrigerator door of claim 43 , wherein the coating has a taber haze of less than about 1% at 100 cycles with 500 gram load and a CS-10F load using ASTM D 4060 testing.
54. The refrigerator door of claim 43 , wherein the coating exhibits a hardness of about 2H to about 8H using ASTM D 3363.
55. The refrigerator door of claim 54 , wherein the coating exhibits a hardness of about 4H to about 6H using ASTM D 3363.
56. The refrigerator door of claim 43 , wherein substantially no fog forms on the portion of the substrate having the coating thereon when the substrate has an initial surface temperature of less than about 0° C., and is then exposed to a moist air ambient with a dewpoint temperature equal to or greater than the surface temperature for a period of time, the period of time being greater than about 3 seconds.
57. The refrigerator door of claim 56 , wherein the period of time is greater than about 6 seconds.
58. The refrigerator door of claim 56 , wherein the period of time is greater than about 10 seconds.
59. The refrigerator door of claim 56 , wherein the period of time is greater than about 30 seconds.
60. The refrigerator door of claim 56 , wherein the period of time is greater than about one minute.
61. The refrigerator door of claim 56 , wherein the period of time is greater than about five minutes.
62. The refrigerator door of claim 43 , wherein substantially no fog forms on the portion of the substrate having the coating thereon when the substrate has an initial surface temperature of less than about −5° C., and is then exposed to a moist air ambient with a dewpoint temperature equal to or greater than the surface temperature for a period of time, the period of time being greater than about 3 seconds.
63. The refrigerator door of claim 62 , wherein the period of time is greater than about 6 seconds.
64. The refrigerator door of claim 62 , wherein the period of time is greater than about 10 seconds.
65. The refrigerator door of claim 62 , wherein the period of time is greater than about one minute.
66. The refrigerator door of claim 62 , wherein the period of time is greater than about five minutes.
67. The refrigerator door of claim 43 , wherein substantially no fog forms on the portion of the substrate having the coating thereon when the substrate has an initial surface temperature of less than about −10° C., and is then exposed to a moist air ambient with a dewpoint temperature equal to or greater than the surface temperature for a period of time, the period of time being greater than about 3 seconds.
68. The refrigerator door of claim 67 , wherein the period of time is greater than about 6 seconds.
69. The refrigerator door of claim 67 , wherein the period of time is greater than about 10 seconds.
70. The refrigerator door of claim 67 , wherein the period of time is greater than about one minute.
71. The refrigerator door of claim 67 , wherein the period of time is greater than about five minutes.
72. The refrigerator door of claim 43 , wherein substantially no fog forms on the portion of the substrate having the coating thereon when the substrate has an initial surface temperature of less than about −15° C., and is then exposed to a moist air ambient with a dewpoint temperature equal to or greater than the surface temperature for a period of time, the period of time being greater than about 6 seconds.
73. The refrigerator door of claim 72 , wherein the period of time is greater than about ten seconds.
74. The refrigerator door of claim 72 , wherein the period of time is greater than about thirty seconds.
75. The refrigerator door of claim 72 , wherein the period of time is greater than about one minute.
76. The refrigerator door of claim 72 , wherein the period of time is greater than about five minutes.
77. The refrigerator door of claim 43 , wherein substantially no fog forms on the portion of the substrate having the coating thereon when the substrate has an initial surface temperature of less than about −18° C., and is then exposed to a moist air ambient with a dewpoint temperature equal to or greater than the surface temperature for a period of time, the period of time being greater than about 6 seconds.
78. The refrigerator door of claim 77 , wherein the period of time is greater than about 10 seconds.
79. The refrigerator door of claim 77 , wherein the period of time is greater than about 30 seconds.
80. The refrigerator door of claim 77 , wherein the period of time is greater than about one minute.
81. The refrigerator door of claim 77 , wherein the period of time is greater than about five minutes.
82. The refrigerator door of claim 77 , wherein the period of time is greater than about fifteen minutes.
83. The refrigerator door of claim 43 , wherein the refrigerator door further comprises another substrate having a low-emissivity surface or a low-emissivity coating thereon.
84. The refrigerator door of claim 83 , wherein the low-emissivity surface or coating does not substantially emit radiation above about 0.7 microns.
85. The refrigerator door of claim 84 , wherein the low-emissivity surface or coating does not substantially emit radiation between about 0.7 and about 2.7 microns.
86. The refrigerator door of claim 83 , wherein the low-emissivity surface or coating has a visible transmittance of about 70% to about 90%.
87. The refrigerator door of claim 43 , wherein the substrate is transparent and the coating exhibits less than about 0.5% detectable haze by hazemeter.
88. The refrigerator door of claim 43 , wherein the life of the coating is greater than about two years.
89. The refrigerator door of claim 43 , wherein the life of the coating is greater than about 5 years.