Display device including bonding member
A display device includes a display panel including a front surface and a second surface which is opposite to the front surface; a front laminated structure attached to the front surface of the display panel; and a rear laminated structure attached to the second surface of the display panel. Each of the front laminated structure and the rear laminated structure includes a bonding member, and an average modulus of the bonding member of the front laminated structure is smaller than an average modulus of the bonding member of the rear laminated structure.
1. A display device comprising:
a display panel including a front surface and a rear surface opposite to each other;
a front laminated structure attached to the front surface of the display panel; and
a rear laminated structure attached to the rear surface of the display panel,
wherein
each of the front laminated structure and the rear laminated structure includes a bonding member, and
an average indenter-measured modulus of the bonding member within the front laminated structure is smaller than an average indenter-measured modulus of the bonding member within the rear laminated structure.
2. The display device of claim 1 , wherein
the front laminated structure includes a cover window and the bonding member including a window bonding member which is attached to the cover window and disposed between the front surface of the display panel and the cover window, and
the window bonding member has an indenter-measured modulus of about 50 kilopascals to about 1 megapascal.
3. The display device of claim 2 , wherein a creep value of the window bonding member ranges from about 30% to about 70%.
4. The display device of claim 3 , wherein
the window bonding member has a thickness of about 300 micrometers or less to define a thin film window bonding member, and
the indenter-measured modulus of about 50 kilopascals to about 1 megapascal and the creep value from about 30% to about 70% are measured values of the thin film window bonding member.
5. The display device of claim 3 , wherein
the window bonding member separated from the display device defines a separated window bonding member, and
the indenter-measured modulus of about 50 kilopascals to about 1 megapascal and the creep value from about 30% to about 70% are indenter-measured values of the separated window bonding member.
6. The display device of claim 5 , wherein the indenter-measured values of the separated window bonding member are defined by an indentation depth measuring process, the indentation depth measuring process comprising:
a loading process in which a load is applied to an indenter while the indenter is being pressed to the separated window bonding member, and
a measuring process in which an indentation depth is measured after maintaining a maximum load applied the indenter being pressed to the separated window bonding member for a predetermined time period.
7. The display device of claim 6 , wherein the indentation depth measuring process further comprises the indenter having a ball shape.
8. The display device of claim 3 , wherein
the front laminated structure further includes a cover window protective layer,
the bonding member of the front laminated structure further includes a protective layer bonding member which attaches the cover window protective layer to the cover window,
within the front laminated structure, the protective layer bonding member is further from the display panel than the window bonding member, and
the protective layer bonding member has an indenter-measured modulus of about 50 kilopascals to about 1 megapascal and a creep value which ranges from about 30% to about 70%.
9. The display device of claim 8 , wherein the indenter-measured modulus of the protective layer bonding member is smaller than the indenter-measured modulus of the window bonding member.
10. The display device of claim 3 , wherein
the front laminated structure further includes a polarizing member,
the bonding member of the front laminated structure further includes a polarizing member bonding member which attaches the polarizing member to the front surface of the display panel,
within the front laminated structure, the window bonding member is further from the display panel than the polarizing member bonding member,
the polarizing member bonding member includes an indenter-measured modulus of about 100 kilopascals to about 10 megapascals and a creep value which ranges from about 30% to about 70%, and
the indenter-measured modulus of the polarizing member bonding member is larger than the indenter-measured modulus of the window bonding member.
11. The display device of claim 3 , wherein the rear laminated structure includes:
a heat dissipation member facing the rear surface of the display panel, and
a polymer film layer between the heat dissipation member and the rear surface of the display panel.
12. The display device of claim 11 , wherein
the rear laminated structure further includes:
the bonding member including:
a polymer film bonding member which attaches the polymer film layer to the rear surface of the display panel, and
a heat dissipation member bonding member which attaches the heat dissipation member to the polymer film layer,
an indenter-measured modulus of each of the polymer film bonding member and the heat dissipation member bonding member is about 100 kilopascals to about 10 megapascals and is larger than the indenter-measured modulus of the window bonding member, and
a creep value of each of the polymer film bonding member and the heat dissipation member bonding member ranges from about 30% to about 70%.
13. The display device of claim 12 , wherein
the rear laminated structure further includes a buffer member disposed between the polymer film layer and the heat dissipation member,
the bonding member of the rear laminated structure further includes a buffer member bonding member which attaches the buffer member to the polymer film layer,
an indenter-measured modulus of the buffer member bonding member is about 100 kilopascals to about 10 megapascals and is larger than the indenter-measured modulus of the window bonding member, and
a creep value of the buffer member bonding member ranges from about 30% to about 70%.
14. The display device of claim 3 , wherein the window bonding member has a peel force of 200 gf/inch or more when peeled off at a peeling angle of 180° at a speed of 300 mm/min in a state of being attached on a glass substrate.
15. The display device of claim 1 , wherein the front surface of the display panel defines a display screen of the display device at which an image is displayed.
16. The display device of claim 15 , wherein
the display device is foldable, and
the display device which is in-folded disposes portions of the display screen facing each other.
17. A display device comprising:
a display panel which is foldable and includes a display surface at which an image is displayed and a rear surface which is opposite to the display surface;
a front laminated structure attached to the display surface of the display panel and foldable together with the display panel, the front laminated structure including a first thin film adhesive layer having a thickness of about 300 micrometers or less and an indenter-measured modulus of about 50 kilopascals to about 1 megapascal; and
a rear laminated structure attached to the rear surface of the display panel and foldable together with the display panel,
wherein the display device which ‘is in-folded disposes portions of the display surface facing each other with the first thin film adhesive layer therebetween.
18. The display device of claim 17 , wherein
the rear laminated structure includes a second thin film adhesive layer having a thickness of about 300 micrometers or less, and
an indenter-measured modulus of the second thin film adhesive layer is about 100 kilopascals to about 10 megapascals and is larger than the indenter-measured modulus of the first thin film adhesive layer.
19. The display device of claim 18 , wherein
the front laminated structure further includes a third thin film adhesive layer which is closer to the display panel than the first thin film adhesive layer and has a thickness of about 300 micrometers or less, and
an indenter-measured modulus of the third thin film adhesive layer is about 100 kilopascals to about 10 megapascals and is larger than the indenter-measured modulus of the first thin film adhesive layer.
20. The display device of claim 17 , wherein
the indenter-measured modulus of about 50 kilopascals to about 1 megapascal is an indenter-measured value of the first thin film adhesive layer, and
the indenter-measured value of the first thin film adhesive layer is defined by an indentation depth measuring process, the indentation depth measuring process comprising:
a loading process in which a load is applied to an indenter while the indenter is being pressed to the first thin film adhesive layer, and
a measuring process in which an indentation depth is measured after maintaining a maximum load applied the indenter for a predetermined time period.