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EP-4737996-A1 - LIGHT CONTROL MEMBER AND LAMINATED PLATE

EP4737996A1EP 4737996 A1EP4737996 A1EP 4737996A1EP-4737996-A1

Abstract

A light modulating member (20) includes a first member (30), a second member (40), a liquid crystal layer (50), a plurality of first bead spacers (60), and a plurality of second bead spacers (70). The first member (30) includes a first base member (31). The second member (40) includes a second base member (41) that is opposed to the first base member (31). The liquid crystal layer (50) is located between the first member (30) and the second member (40). The plurality of first bead spacers (60) and the plurality of second bead spacers (70) are provided between the first member (30) and the second member (40) so as to maintain a thickness of the liquid crystal layer (50). An average particle diameter of the second bead spacers (70) is larger than an average particle diameter of the first bead spacers (60). The second bead spacers (70) are softer than the first bead spacers (60).

Inventors

  • IKEZAWA, TAKAO
  • TAMAKI, ATSUSHI
  • SHIRAISHI, Isamu
  • URIMOTO, Hideaki
  • ASAI, TOSHIAKI

Assignees

  • Dai Nippon Printing Co., Ltd.

Dates

Publication Date
20260506
Application Date
20240627

Claims (20)

  1. A light modulating member comprising: a first member including a first base member; a second member including a second base member opposed to the first base member; a liquid crystal layer located between the first member and the second member; and a plurality of first bead spacers and a plurality of second bead spacers that are provided between the first member and the second member so as to maintain a thickness of the liquid crystal layer, wherein an average particle diameter of the second bead spacers is larger than an average particle diameter of the first bead spacers, and the second bead spacers are softer than the first bead spacers.
  2. The light modulating member according to claim 1, wherein in a case where an amount of deformation of the first bead spacers and an amount of deformation of the second bead spacers are measured by applying a load to the first bead spacers and the second bead spacers up to 5 mN at a speed of 0.29 mN/sec by using a 50-µm square flat indenter, a ratio of the amount of deformation of the second bead spacers to the amount of deformation of the first bead spacers is equal to or more than 3.21 and equal to or less than 4.49.
  3. A light modulating member comprising: a first member including a first base member; a second member including a second base member opposed to the first base member; a liquid crystal layer located between the first member and the second member; and a plurality of first bead spacers and a plurality of second bead spacers that are provided between the first member and the second member so as to maintain a thickness of the liquid crystal layer, wherein an average particle diameter of the second bead spacers is larger than an average particle diameter of the first bead spacers, and in a case where an amount of deformation of the first bead spacers and an amount of deformation of the second bead spacers are measured by applying a load to the first bead spacers and the second bead spacers up to 5 mN at a speed of 0.29 mN/sec by using a 50-µm square flat indenter, a ratio of the amount of deformation of the second bead spacers to the amount of deformation of the first bead spacers is equal to or more than 3.21 and equal to or less than 4.49.
  4. The light modulating member according to claim 1 or 3, wherein an amount of deformation of the second bead spacers measured by applying a load to the second bead spacers up to 5 mN at a speed of 0.29 mN/sec by using a 50-µm square flat indenter is equal to or more than 2.38 µm and equal to or less than 3.32 µm.
  5. A light modulating member comprising: a first member including a first base member; a second member including a second base member opposed to the first base member; a liquid crystal layer located between the first member and the second member; and a plurality of first bead spacers and a plurality of second bead spacers that are provided between the first member and the second member so as to maintain a thickness of the liquid crystal layer, wherein an average particle diameter of the second bead spacers is larger than an average particle diameter of the first bead spacers, and an amount of deformation of the second bead spacers measured by applying a load to the second bead spacers up to 5 mN at a speed of 0.29 mN/sec by using a 50-µm square flat indenter is equal to or more than 2.38 µm and equal to or less than 3.32 µm.
  6. The light modulating member according to any one of claims 1, 3, and 5, wherein in a case where a load is applied to the second bead spacers up to 5 mN at a speed of 0.29 mN/sec by using a 50-µm square flat indenter, an amount by which the second bead spacers are deformed during five seconds where the load is maintained after the load reaches 5 mN is equal to or less than 0.04 µm.
  7. The light modulating member according to any one of claims 1, 3, and 5, wherein the average particle diameter of the second bead spacers is equal to or more than 110% and equal to or less than 130% of the average particle diameter of the first bead spacers.
  8. The light modulating member according to any one of claims 1, 3, and 5, wherein the number of second bead spacers is larger than the number of first bead spacers.
  9. The light modulating member according to any one of claims 1, 3, and 5, wherein a color of the first bead spacers and a color of the second bead spacers are black.
  10. The light modulating member according to any one of claims 1, 3, and 5, wherein the second bead spacers have adhesiveness.
  11. A laminated plate comprising: a first substrate and a second substrate that are opposed to each other; and the light modulating member according to any one of claims 1, 3, and 5 that is located between the first substrate and the second substrate.
  12. The laminated plate according to claim 11, further comprising: a first joining layer that joins the first substrate and the light modulating member to each other; and a second joining layer that joins the second substrate and the light modulating member to each other.
  13. The laminated plate according to claim 12, wherein a thickness of the first joining layer and a thickness of the second joining layer are uniform within a plane.
  14. The laminated plate according to claim 12, wherein the first joining layer and the second joining layer are connected to each other by an insertion member.
  15. The laminated plate according to claim 14, wherein a material of the insertion member is polyethylene terephthalate, polycarbonate, or an OCR.
  16. The laminated plate according to claim 12, wherein an outer periphery fixation member is provided along outer peripheries of the first substrate, the first joining layer, the light modulating member, the second joining layer, and the second substrate.
  17. The laminated plate according to claim 12, wherein a gap layer is provided between the first joining layer and the light modulating member.
  18. The laminated plate according to claim 17, wherein a reflection prevention layer is provided so as to face the gap layer.
  19. The laminated plate according to claim 18, wherein the first substrate is tint glass.
  20. The laminated plate according to claim 17, wherein the first substrate has an anti reflection function.

Description

Technical Field The present disclosure relates to a light modulating member and a laminated plate. Background Art A light modulating member that can regulate visible light transmittance, such as the one disclosed in Patent Literature 1, is known. The light modulating member disclosed in Patent Literature 1 includes, for example, a liquid crystal layer containing liquid crystal molecules. The light modulating member including a liquid crystal layer can change visible light transmittance upon application of a voltage. The light modulating member including a liquid crystal layer is advantageous in that the change in the visible light transmittance is fast. The light modulating member is, for example, used for a transparent part of a partition member such as a window. The liquid crystal layer is located between one pair of plate-shaped members each including a base member. Bead spacers are further located between the one pair of plate-shaped members. The bead spacers are in contact with the one pair of plate-shaped members. The bead spacers appropriately maintain a thickness of the liquid crystal layer. The bead spacers suppress movement of the liquid crystal molecules in the liquid crystal layer. Citation List Patent Literature PTL 1: Japanese Unexamined Patent Application Publication No. 2018-5040 Summary of Invention Technical Problem When the light modulating member is exposed to a high temperature, the liquid crystal layer expands due to heat. This increases a gap between the bead spaces and the plate-shaped members. The liquid crystal molecules can move in the liquid crystal layer between the bead spacers and the plate-shaped members. In a case where the light modulating member including the liquid crystal layer is placed obliquely with respect to a horizontal direction, the liquid crystal molecules can move in the liquid crystal layer and shift downward in the vertical direction due to gravity. The concentrated liquid crystal molecules are visibly conspicuous from an outside of the light modulating member. This may degrade outer appearance of the light modulating member. An object of the present disclosure is to suppress degradation of outer appearance of a light modulating member caused by uneven distribution of liquid crystal molecules. Solution to Problem An embodiment of the present disclosure relates to the following [1] to [20]. [1] A light modulating member including: a first member including a first base member; a second member including a second base member opposed to the first base member; a liquid crystal layer located between the first member and the second member; and a plurality of first bead spacers and a plurality of second bead spacers that are provided between the first member and the second member so as to maintain a thickness of the liquid crystal layer, in which an average particle diameter of the second bead spacers is larger than an average particle diameter of the first bead spacers, and the second bead spacers are softer than the first bead spacers.[2] The light modulating member according to [1], in which in a case where an amount of deformation of the first bead spacers and an amount of deformation of the second bead spacers are measured by applying a load to the first bead spacers and the second bead spacers up to 5 mN at a speed of 0.29 mN/sec by using a 50-µm square flat indenter, a ratio of the amount of deformation of the second bead spacers to the amount of deformation of the first bead spacers is equal to or more than 3.21 and equal to or less than 4.49.[3] A light modulating member including: a first member including a first base member; a second member including a second base member opposed to the first base member; a liquid crystal layer located between the first member and the second member; and a plurality of first bead spacers and a plurality of second bead spacers that are provided between the first member and the second member so as to maintain a thickness of the liquid crystal layer, in which an average particle diameter of the second bead spacers is larger than an average particle diameter of the first bead spacers, and in a case where an amount of deformation of the first bead spacers and an amount of deformation of the second bead spacers are measured by applying a load to the first bead spacers and the second bead spacers up to 5 mN at a speed of 0.29 mN/sec by using a 50-µm square flat indenter, a ratio of the amount of deformation of the second bead spacers to the amount of deformation of the first bead spacers is equal to or more than 3.21 and equal to or less than 4.49.[4] The light modulating member according to any one of [1] to [3], in which an amount of deformation of the second bead spacers measured by applying a load to the second bead spacers up to 5 mN at a speed of 0.29 mN/sec by using a 50-µm square flat indenter is equal to or more than 2.38 µm and equal to or less than 3.32 µm.[5] A light modulating member including: a first member including