Window and display device including the same
Embodiments provide a window and a display device including the window. The window includes a base substrate including a first surface and a second surface which face each other, and a filling portion. The base substrate has a concave portion defined on at least one of the first surface and the second surface, a difference between a refractive index of the base substrate at a wavelength of about 589 nm and a refractive index of the filling portion is less than or equal to about 0.02, a difference between an Abbe No. of the base substrate and an Abbe No. of the filling portion is less than or equal to about 5.0, and the filling portion fills the concave portion. The window and the display thus exhibits satisfactory folding properties and impact resistance, as well as improved optical properties and display quality that prevent reflection color from being viewed.
1 . A window comprising:
a base substrate including a first surface and a second surface which face each other; and
a filling portion, wherein
the base substrate has a concave portion defined on at least one of the first surface and the second surface,
a difference between a refractive index of the base substrate at a wavelength of about 589 nm and a refractive index of the filling portion at a wavelength of about 589 nm is less than or equal to about 0.02,
a difference between an Abbe No. of the base substrate and an Abbe No. of the filling portion is less than or equal to about 5.0,
the filling portion fills the concave portion,
the base substrate is a glass substrate, and
the filling portion comprises:
nanoparticles that include at least one of Al 2 O 3 and glass particles; and
an acrylic polymer resin.
2 . The window of claim 1 , wherein
the window comprises:
a folding portion which is foldable with respect to a virtual folding axis extending in one direction; and
a non-folding portion adjacent to the folding portion, and the concave portion is defined in the folding portion.
3 . The window of claim 1 , wherein the filling portion is formed through a polymerization reaction of a resin composition that comprises:
a base resin including two or more types of acrylic monomers that are different from each other;
a crosslinking agent;
a photoinitiator; and
the nanoparticles.
4 . The window of claim 3 , wherein an amount of the nanoparticles in the resin composition is in a range of about 0.1 wt % to about 10 wt %, with respect to 100 wt % of the base resin.
5 . The window of claim 3 , wherein the base resin comprises an acrylic monomer represented by Formula 1:
wherein in Formula 1,
R 1 is O, a substituted or unsubstituted divalent alkyl group having 1 to 6 carbon atoms, a substituted or unsubstituted divalent alkoxy group having 1 to 6 carbon atoms, or a substituted or unsubstituted divalent aryl group having 6 to 18 carbon atoms,
R 2 is a hydroxy group, a substituted or unsubstituted alkyl group having 1 to 6 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 6 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 18 carbon atoms, and
at least one of R 1 and R 2 comprises a substituted or unsubstituted aryl group having 6 to 18 carbon atoms.
6 . The window of claim 5 , wherein an amount of the acrylic monomer represented by Formula 1 in the base resin is in a range of about 10 wt % to about 40 wt %, with respect to 100 wt % of the base resin.
7 . The window of claim 1 , wherein
a refractive index of the filling portion is in a range of about 1.49 to about 1.51 at a wavelength of about 589 nm, and
the filling portion has an Abbe No. in a range of about 45 to about 50.
8 . The window of claim 7 , wherein
a glass transition temperature of the filling portion is less than or equal to about −20° C., and
the filling portion has an elongation greater than or equal to about 200%.
9 . The window of claim 1 , further comprising:
a cover layer disposed on a surface of the base substrate in which the concave portion is defined, wherein
the cover layer includes a same material as the filling portion.
10 . The window of claim 9 , wherein the cover layer is formed as a single body with the filling portion.
11 . The window of claim 1 , wherein a thickness of a portion of the base substrate in which the concave portion is not defined is greater than or equal to about 100 μm.
12 . A display device comprising:
a display module; and
a window disposed on the display module, wherein
the window includes:
a base substrate including a first surface and a second surface which face each other; and
a filling portion,
the base substrate has a concave portion defined on at least one of the first surface and the second surface,
a difference between a refractive index of the base substrate at a wavelength of about 589 nm and a refractive index of the filling portion at a wavelength of about 589 nm is less than or equal to about 0.02,
a difference between an Abbe No. of the base substrate and an Abbe No. of the filling portion is less than or equal to about 5.0,
the filling portion fills the concave portion,
the base substrate is a glass substrate, and
the filling portion comprises:
nanoparticles that include at least one of Al 2 O 3 and glass particles; and
an acrylic polymer resin.
13 . The display device of claim 12 , wherein
the display module comprises:
a folding display portion which is foldable with respect to a folding axis extending in one direction; and
a non-folding display portion adjacent to the folding display portion, the window comprises:
a folding portion corresponding to the folding display portion; and
a non-folding portion corresponding to the non-folding display portion, and the concave portion is defined in the folding portion.
14 . The display device of claim 12 , wherein
the acrylic polymer resin is formed through a polymerization reaction of a base resin comprising two or more types of acrylic monomers that are different from each other, and
the base resin comprises an acrylic monomer represented by Formula 1:
wherein in Formula 1,
R 1 is O, a substituted or unsubstituted divalent alkyl group having 1 to 6 carbon atoms, a substituted or unsubstituted divalent alkoxy group having 1 to 6 carbon atoms, or a substituted or unsubstituted divalent aryl group having 6 to 18 carbon atoms,
R 2 is a hydroxy group, a substituted or unsubstituted alkyl group having 1 to 6 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 6 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 18 carbon atoms, and
at least one of R 1 and R 2 comprises a substituted or unsubstituted aryl group having 6 to 18 carbon atoms.
15 . The display device of claim 14 , wherein an amount of the nanoparticles in the display device is in a range of about 0.1 wt % to about 10 wt %, with respect to 100 wt % of the base resin.
16 . The display device of claim 12 , wherein
a refractive index of the filling portion is in a range of about 1.49 to about 1.51 at a wavelength of about 589 nm, and
the filling portion has an Abbe No. in a range of about 45 to about 50.
17 . The display device of claim 16 , wherein
a glass transition temperature of the filling portion is less than or equal to about 31 20° C., and
the filling portion has an elongation greater than or equal to about 200%.
18 . The display device of claim 12 , wherein
the window further comprises:
a cover layer disposed on a surface of the base substrate in which the concave portion is defined, and
the cover layer includes a same material as the filling portion.
19 . A display device comprising:
a folding region which is foldable with respect to a virtual folding axis extending in one direction;
a non-folding region adjacent to the folding region;
a display module; and
a window made of glass disposed on the display module, wherein
the window includes:
a lower surface adjacent to the display module;
an upper surface facing the lower surface;
a concave portion depressed from at least one of the upper surface and the lower surface; and
a filling portion filled in the concave portion,
a refractive index of the filling portion is in a range of about 0.49 to about 1.51 at a wavelength of about 589 nm,
the filling portion has an Abbe No. in a range of about 45 to about 50,
a glass transition temperature of the filling portion is less than or equal to about −20° C., and
the filling portion has an elongation greater than or equal to about 200%.
20 . The display device of claim 19 , wherein the filling portion comprises:
nanoparticles that include at least one of Al 2 O 3 and glass particles; and
an acrylic polymer resin.
21 . The display device of claim 20 , wherein the filling portion is formed through a polymerization reaction of a resin composition that comprises:
a base resin including two or more types of acrylic monomers that are different from each other,
a crosslinking agent;
a photoinitiator; and
the nanoparticles.
22 . The display device of claim 21 , wherein an amount of the nanoparticles in the resin composition is in a range of about 0.1 wt % to about 10 wt %, with respect to 100 wt % of the base resin.
23 . The display device of claim 21 , wherein the base resin comprises an acrylic monomer represented by Formula 1:
wherein in Formula 1,
R 1 is O, a substituted or unsubstituted divalent alkyl group having 1 to 6 carbon atoms, a substituted or unsubstituted divalent alkoxy group having 1 to 6 carbon atoms, or a substituted or unsubstituted divalent aryl group having 6 to 18 carbon atoms,
R 2 is a hydroxy group, a substituted or unsubstituted alkyl group having 1 to 6 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 6 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 18 carbon atoms, and
at least one of R 1 and R 2 comprises a substituted or unsubstituted aryl group having 6 to 18 carbon atoms.
24 . The display device of claim 23 , wherein an amount of the acrylic monomer represented by Formula 1 in the base resin is in a range of about 10 wt % to about 40 wt %, with respect to 100 wt % of the base resin.