Electrochromic element, method for manufacturing same, and window device including same

A window device, comprising:

• a frame;
• a window mounted on the frame;
• and
• an electrochromic element disposed in the window,
• wherein the electrochromic element comprises:
• a first substrate;
• a first transparent electrode disposed on the first substrate;
• a first discoloration layer disposed on the first transparent electrode;
• an electrolyte layer disposed on the first discoloration layer;
• a second discoloration layer disposed on the electrolyte layer;
• a second transparent electrode disposed on the second discoloration layer;
• and
• a second substrate disposed on the second transparent electrode,
• wherein a coloring transmittance deviation after a twist test, measured by a measurement method below, is less than 0.4:
• [Measurement Method]
• 1) The electrochromic element is cut to a size of 20 cm in length and 4 cm in width.
• 2) Opposite ends of the cut electrochromic element are gripped.
• 3) The gripped opposite ends of the electrochromic element are pulled with a force of 1 N.
• 4) The pulled opposite ends of the electrochromic element are twisted at an angle of 15° to each other.
• 5) The twisted state of the electrochromic element is maintained for 1 minute, and then released, thus completing a twist test.
• 6) A driving voltage is applied to the electrochromic element that has been subjected to the twist test, and the electrochromic element is colored.
• 7) In the colored electrochromic element, a central region of 16 cm in length and 3 cm in width is defined.
• 8) A first transmittance of each measurement region of 1 cm×1 cm in the central region is measured.
• 9) The coloring transmittance deviation is a value obtained by dividing a difference between a maximum transmittance and minimum transmittance among the first transmittances of the measurement regions by an average transmittance of the first transmittances of the measurement regions.