Display medium, and manufacturing method and apparatus of the display medium
A display medium including: a pair of substrates; a pair of electrodes disposed on the pair of substrates, and facing each other; and a functional layer and a display layer disposed between the pair of electrodes with an adhesive layer disposed between the functional layer and the display layer. The display layer includes a binder and microcapsules dispersed in the binder. The microcapsules have a polymer serving as a wall material, and a liquid crystal enclosed therein. A shape of an interface of the display layer at least on the side of the adhesive layer in a cross section along a thickness direction of the disposed layers is an irregular line having a distance between a highest protruding portion and a lowest depressed portion is from about 0.5 μm to about 2.0 μm.
1. A display medium comprising:
a pair of substrates;
a pair of electrodes disposed on the pair of substrates and facing each other; and
a functional layer and a display layer disposed between the pair of electrodes with an adhesive layer disposed between the functional layer and the display layer,
the display layer comprising a binder and microcapsules dispersed in the binder, the microcapsules comprising a polymer serving as a wall material and a liquid crystal enclosed therein, and
a shape of an interface of the display layer at least on the side of the adhesive layer in a cross section along a thickness direction of the disposed layers being an irregular line having a distance between a highest protruding portion and a lowest depressed portion from about 0.5 μm about 2.0 μm.
2. The display medium according to claim 1 , wherein the average particle size of the microcapsules is from about 4 μm to about 20 μM.
3. The display medium according to claim 1 , wherein the liquid crystal is cholesteric liquid crystal.
4. The display medium according to claim 1 , wherein the display layer comprises at least two layers in which microcapsules having liquid crystals that have different selective wavelengths are enclosed, and a shape of an interface between the at least two layers in a cross section along a thickness direction of the disposed layers being an irregular line such that a distance between a highest protruding portion and a lowest depressed portion is in the range from about 0.5 μm to about 2 μm.
5. A manufacturing apparatus of the display medium according to claim 1 , comprising:
a display layer forming part that forms a display layer on a first substrate;
a functional layer forming part that forms a functional layer on a second substrate;
a softening/planarizing part that softens and planarizes a surface of the formed display layer; and
a bonding part that bonds the display layer having the planarized surface, and the functional layer to each other.
6. A manufacturing method of the display medium according to claim 1 , comprising:
forming a display layer on a first substrate;
forming a functional layer on a second substrate;
softening and planarizing a surface of the formed display layer; and
bonding the display layer having the planarized surface, and the functional layer to each other.
7. The manufacturing method of a display medium according to claim 6 , wherein in the softening of the softening and planarizing, a liquid is made to permeate into the surface of the display layer causing it to swell.
8. The manufacturing method of a display medium according to claim 6 , wherein an arithmetic average roughness Ra of the surface of the display layer which has been planarized by the softening and planarizing is about 0.5 μm or less.
9. The manufacturing method of a display medium according to claim 6 , wherein the display layer is softened in advance of a planarization process to obtain a smoothness at a low pressure.
10. The display medium according to claim 1 , wherein the display layer is softened in advance of a planarization process to obtain a smoothness at a low pressure.