Electrochromic device
View Patent ↗The invention relates to an electrochromic device including a first non-tempered glass substrate (S 1 ), the linear thermal expansion coefficient of which is between 35 and 60·10 −7 /° C., said substrate (S 1 ) being coated with a stack including at least one transparent electrically conductive layer ( 2, 4 ), an electrochromic material layer (EC 2 ), an ion-conductive electrolyte layer (EL), and a counter electrode (EC 1 ).
1. An electrochromic device comprising a first substrate of untempered glass of which the linear thermal expansion coefficient is between about 35 and about 60×10 −7 /° C., said substrate being coated with a stack comprising at least one transparent electro-conductive layer, a layer of an electrochromic material, a layer of an ionic electrolytic conductor and a counter-electrode, and wherein said first substrate is laminated to a second substrate substantially the same size as said first substrate, and wherein said second substrate has a linear thermal expansion coefficient between about 35 and about 60×10 −7 /° C.
2. The device of claim 1 , wherein said first glass substrate possesses a linear thermal expansion coefficient less than or equal to about 50×10 −7 /° C., or less than or equal to about 45×10 −7 /° C.
3. The device of claim 1 , wherein said first glass substrate has a chemical composition comprising the following, within the mass limits defined hereunder:
SiO 2
about 50 through 82%
B 2 O 3
about 0 through 20%
Al 2 O 3
about 0 through 22%
MgO
about 0 through 10%
CaO
about 0 through 15%
SrO
about 0 through 5%
BaO
about 0 through 15%
CaO + MgO +
about 0 through 15%
BaO + SrO
Na 2 O
about 0 through 6%
K 2 O
about 0 through 8%, and
Na 2 O + K 2 O
about 0 through 8%.
4. The device of claim 1 , wherein said first glass substrate has a chemical composition comprising the following constituents, with the mass limits defined below:
SiO 2
about 50 through 60%
B 2 O 3
about 10 through 15%
Al 2 O 3
about 10 through 15%
MgO
about 2 through 5%
CaO
about 2 through 5%
SrO
about 0 through 1%
BaO
about 0 through 1%
CaO + MgO +
about 5 through 15%
BaO + SrO
Na 2 O
about 0 through 5%
K 2 O
about 0 through 5%, and
Na 2 O + K 2 O
about 1 through 6%.
5. The device of claim 1 , wherein said first substrate comprises, in order, starting from an initial substrate or in the reverse order:
a transparent electro-conductive layer,
a counter-electrode,
an ionic conductive electrolyte layer,
a layer of an electrochromic material, and
a second transparent electro-conductive layer.
6. The device of claim 1 , wherein the electrochromic material is based on a material selected from the group consisting of tungsten oxide and iridium oxide.
7. The device of claim 1 , wherein the counter-electrode comprises a material selected from the group consisting of tungsten, nickel, iridium, chromium, iron, cobalt, rhodium, and mixed oxides of at least two of these oxides.
8. The device of claim 1 , wherein the electrolyte comprises a mineral layer forming an ionic conductor that is electrically insulated.
9. A glazing for a building or vehicle partition, rear-view mirror or indicator board comprising the device of claim 1 .
10. The device of claim 7 , wherein said mixed oxide is selected from a mixed nickel and tungsten oxide.
11. The device of claim 1 , wherein a composition of said first substrate comprises the following
SiO 2
about 57 through 70.5%
B 2 O 3
about 0 through 10%
Al 2 O 2
about 10 through 14.6%
MgO
about 0.05 through 8%
CaO
about 2.5 through 17.5%
SrO
about 0 through 0.2%
BaO
about 0 through 13%;
and wherein said linear thermal expansion coefficient ranges from about 42 to about 50×10 −7 /° C.
12. The device of claim 1 , wherein a composition of said first substrate comprises the following
SiO 2
about 51.9 through 74.9%
B 2 O 3
about 3 through 18%
Al 2 O 2
about 1.7 through 20.5%
MgO
about 0.4 through 8.9%
CaO
about 0.6 through 11.4%
SrO
about 0 through 1.3%
BaO
about 0 through 5.1%;
and wherein said linear thermal expansion coefficient ranges from about 36 to about 48×10 −7 /° C.
13. The electrochromic device of claim 1 , wherein said electrochromic device further comprises a polymer sheet between said second substrate and an upper electro-conductive layer.
14. The electrochromic device of claim 1 , wherein said stack is laminated between said first and second substrates.
15. An electrochromic device comprising a first substrate of untempered glass of which the linear thermal expansion coefficient is between about 35 and about 60×10 −7 /° C., said substrate being coated with a stack comprising at least one transparent electro-conductive layer, a layer of an electrochromic material, a layer of an ionic electrolytic conductor and a counter-electrode, and wherein said first substrate is strengthened by combining it with a second substrate substantially the same size as said first substrate, and wherein said second substrate has a linear thermal expansion coefficient between about 35 and about 60×10 −7 /° C.