Bendable articles including adhesive layer with a dynamic elastic modulus
Articles including a substrate, a cover glass layer disposed over a top surface of the substrate, and an adhesive layer having a dynamic elastic modulus disposed between a bottom surface of the cover glass layer and the top surface of the substrate. The cover glass layer may have a thickness in the range of 1 micron to 200 microns. The dynamic elastic modulus of the adhesive layer may include a first elastic modulus in the range of 10 kPa to 1000 kPa measured at a stress frequency in the range of 0 Hertz to 5 Hertz and a temperature of 23 degrees C., and a second elastic modulus of 500 MPa or more measured at a stress frequency in the range of 10 Hertz to 1000 Hertz and a temperature of 23 degrees C. The adhesive layer may be optically transparent. The articles may be bendable electronic display devices or bendable electronic display device modules.
1. An article comprising:
a substrate;
a cover glass layer disposed over a top surface of the substrate, the cover glass layer comprising a thickness in a range of 1 micron to 200 microns; and
an adhesive layer disposed between a bottom surface of the cover glass layer and the top surface of the substrate, the adhesive layer comprising a dynamic elastic modulus comprising:
a first elastic modulus in a range of 10 kPa to 1000 kPa measured at a stress frequency in a range of 0 Hertz to 5 Hertz and a temperature of 23 degrees C., and
a second elastic modulus of 500 MPa or more measured at a stress frequency in a range of 10 Hertz to 1000 Hertz and a temperature of 23 degrees C.
2. The article of claim 1 , wherein the second elastic modulus is in a range of 500 MPa to 10 GPa.
3. The article of claim 1 , wherein the first elastic modulus is in a range of 10 kPa to 1000 kPa across the stress frequency range of 0 Hertz to 5 Hertz.
4. The article of claim 1 , wherein the adhesive layer is optically transparent.
5. The article of claim 1 , wherein the cover glass layer comprises a thickness in a range of 1 micron to 125 microns.
6. The article of claim 1 , wherein the cover glass layer is directly bonded to the top surface of the substrate with the adhesive layer.
7. The article of claim 1 , wherein the adhesive layer comprises a viscoelastic material.
8. The article of claim 1 , wherein the adhesive layer comprises a shear thickening material.
9. The article of claim 8 , wherein the shear thickening material comprises colloidal nanoparticles dispersed in a solution, and wherein an average particle size of the colloidal nanoparticles is 200 nanometers or less.
10. The article of claim 9 , wherein the colloidal nanoparticles comprise a first refractive index and the solution comprises a second refractive index, and a difference between the first refractive index and the second refractive index is 0.02 or less.
11. The article of claim 1 , wherein the substrate comprises an electronic display comprising a display surface defining at least a portion of the top surface of the substrate.
12. The article of claim 1 , further comprising a coating layer disposed on a top surface of the cover glass layer, wherein the coating layer comprises at least one of an anti-reflection coating layer, an anti-glare coating layer, an anti-fingerprint coating layer, an anti-microbial coating layer, or an easy-to-clean coating layer.
13. The article of claim 1 , wherein at least one of a top surface or the bottom surface of the cover glass layer comprises a compressive stress, and a concentration of metal oxide through a thickness of the cover glass layer is different at two or more points.
14. The article of claim 1 , further comprising:
a housing comprising a front surface, a back surface and side surfaces; and
electrical components at least partially within the housing, the electrical components comprising a controller, a memory, and an electronic display, the electronic display at or adjacent the front surface of the housing,
wherein the cover glass layer forms at least a portion of the housing.
15. An electronic display component, comprising:
an electronic display comprising a display surface;
a cover glass layer disposed over the display surface, the cover glass layer comprising a thickness in a range of 1 micron to 200 microns; and
an optically transparent adhesive layer disposed between a bottom surface of the cover glass layer and the display surface of the electronic display, the adhesive layer comprising a dynamic elastic modulus comprising:
a first elastic modulus in a range of 10 kPa to 1000 kPa measured at a stress frequency in a range of 0 Hertz to 5 Hertz and a temperature of 23 degrees C., and
a second elastic modulus of 500 MPa or more measured at a stress frequency in a range of 10 Hertz to 1000 Hertz and a temperature of 23 degrees C.
16. The electronic display component of claim 15 , wherein the optically transparent adhesive layer comprises a viscoelastic material.
17. The electronic display component of claim 15 , wherein the optically transparent adhesive layer comprises a shear thickening material.
18. The electronic display component of claim 15 , wherein the optically transparent adhesive layer comprises a thickness in a range of 25 microns to 75 microns.
19. A method of making an electronic display component, the method comprising:
disposing an optically transparent adhesive layer between a top, user-facing surface of an electronic display and a bottom surface of a glass layer, the glass layer comprising a top, user-facing surface opposite the bottom surface and a thickness in a range of 1 micron to 200 microns, and
wherein the adhesive layer comprises a dynamic elastic modulus comprising:
a first elastic modulus in a range of 10 kPa to 1000 kPa measured at a stress frequency in a range of 0 Hertz to 5 Hertz and a temperature of 23 degrees C., and
a second elastic modulus of 500 MPa or more measured at a stress frequency in a range of 10 Hertz to 1000 Hertz and a temperature of 23 degrees C.