Stretchable device

Abstract

A stretchable device including a substrate, an electronic structure layer, a first stretchable capping layer and a second stretchable capping layer is provided. The electronic structure layer is disposed on the substrate. The first stretchable capping layer is disposed between the electronic structure layer and the second stretchable capping layer. A Young's modulus of the second stretchable capping layer is greater than a Young's modulus of the first stretchable capping layer.

Description

[Technical Field]

[0001] This invention relates to a stretchable device. [Previous Technology]

[0002] In existing stretchable display devices, only a single layer of OC (overcoating) adhesive is applied to the display structure layer. This OC adhesive is typically a surface-drying material, and its cured surface is smooth and non-sticky. For stretchable display devices with an overall stretching range of 1% to 5%, this OC adhesive meets the stretching requirements and does not cause problems such as protective film adhesion. However, for stretchable display devices requiring an overall stretching range greater than 10%, the elastic modulus of this OC adhesive is too high. However, if an OC adhesive with a lower elastic modulus is used instead, the problem of protective film adhesion may occur. [Summary of the Invention]

[0003] The present invention provides a stretchable device with good tensile deformation capability and high yield.

[0004] According to an embodiment of the present invention, a stretchable device is provided, including a substrate, an electronic structure layer, a first stretchable cover layer, and a second stretchable cover layer. The electronic structure layer is disposed on the substrate. The first stretchable cover layer is located between the electronic structure layer and the second stretchable cover layer. The elastic modulus of the second stretchable cover layer is greater than the elastic modulus of the first stretchable cover layer.

[0005] Based on the above, in the stretchable device provided according to the embodiment of the present invention, a stretchable cover layer with a small elastic modulus and a stretchable cover layer with a large elastic modulus are sequentially arranged on the electronic structure layer. The former can avoid excessive stress on the electronic structure layer, and the latter can prevent the protective film to stick or the adhesive layer to break, thereby greatly improving the yield of the stretchable device, and the stretchable device can still have good tensile deformation capability.

[0006] In order to make the above features and advantages of the present invention more apparent and understandable, specific embodiments are described below, and detailed descriptions are given in conjunction with the accompanying drawings.

Implementation Method

[0007] Referring to FIG1, a schematic diagram of a stretchable device according to an embodiment of the present invention is shown.

[0008] The stretchable device 1 of this embodiment has an active region AR and a peripheral region PR, and includes a substrate 10, an electronic structure layer 200, a stretchable cover layer 101, and a stretchable cover layer 102. The electronic structure layer 200 includes at least one electronic component 201. The electronic structure layer 200, the stretchable cover layer 101, and the stretchable cover layer 102 are sequentially disposed on the substrate 10 along the Z direction. The elastic modulus of the stretchable cover layer 102 is greater than that of the stretchable cover layer 101.

[0009] It should be noted that, in this embodiment, the elastic modulus of the stretchable cover layer 101 closer to the electronic structure layer 200 is smaller, which can prevent excessive stress on the electronic structure layer 200 when the stretchable device 1 is stretched. In addition, the surface viscosity of the stretchable cover layer 102 with a larger elastic modulus after curing is lower than that of the stretchable cover layer 101 with a smaller elastic modulus after curing. Therefore, the surface of the stretchable cover layer 102 away from the electronic structure layer 200 is more suitable for configuring a protective film than the surface of the stretchable cover layer 101 away from the electronic structure layer 200, which can prevent the phenomenon of protective film adhesion.

[0010] In some embodiments, the elastic modulus of the stretchable cover layer 102 may fall within the range of 30 MPa to 1 GPa, and / or the elastic modulus of the stretchable cover layer 101 may fall within the range of 1 MPa to 10 MPa. In some embodiments, the stretchable cover layer 101 has an elongation falling within the range of 100% to 1500%. In some embodiments, the stretchable cover layer 101 has a maximum elongation, the stretchable cover layer 102 has a maximum elongation, and the ratio of the maximum elongation of the stretchable cover layer 102 to the maximum elongation of the stretchable cover layer 101 is less than 0.7. Accordingly, the stretchable device may have a stretchability greater than 5%, or even greater than 10%, without excessive stress on the electronic structure layer 200 or protective film adhesion.

[0011] Referring to FIG1, the stretchable device 1 of this embodiment may further include an adhesive layer GL, the elastic modulus of which is less than that of the stretchable cover layer 101 and falls within the range of 0.01 MPa to 1 MPa. In a comparative example, the stretchable device 1 does not have a stretchable cover layer 102, and the adhesive layer GL is disposed on the surface of the stretchable cover layer 101 away from the electronic structure layer 200. When the stretchable device 1 of this comparative example is stretched, the adhesive layer GL thereon is prone to cohesive failure because the stretchable cover layer 101 has a smaller elastic modulus. In contrast, in the embodiment shown in FIG1, since the stretchable cover layer 102 is located between the adhesive layer GL and the stretchable cover layer 101, the stretchable cover layer 102, which has a higher elastic modulus, can prevent the adhesive layer GL from cohesively failing when the stretchable device 1 is stretched.

[0012] As shown in FIG1, the stretchable device 1 of this embodiment may further include a stretchable layer 303, wherein the adhesive layer GL is used to adhere the stretchable layer 303 and the stretchable cover layer 102. In some embodiments, the stretchable layer 303 is a protective film, but is not limited thereto.

[0013] In some embodiments, the stretchable device 1 may be a stretchable display panel, the electronic component 201 may be a light-emitting diode, the adhesive layer GL may be a transparent optical adhesive layer, and the stretchable layer 303 may be a stretchable touch layer, but is not limited thereto.

[0014] Referring also to FIG1, in some embodiments, the stretchable device 1 may also satisfy the condition E2*H2>3*E1*H1, where H1 is the maximum thickness of the stretchable cover layer 101 in the normal direction (Z direction) of the substrate 10, H2 is the maximum thickness of the stretchable cover layer 102 in the Z direction, E1 is the elastic modulus of the stretchable cover layer 101, and E2 is the elastic modulus of the stretchable cover layer 102. Accordingly, the stretchable cover layer 102 may have sufficiently high stiffness to drive the deformed stretchable device 1 to spring back (or retract).

[0015] It should be noted that in some embodiments, the stretchable device 1 may have a stretchable region and a non-stretchable region. In the stretchable region of the stretchable device 1, the stretchable cover layer 102 may be disposed on the side of the stretchable cover layer 101 away from the substrate 10, as shown in FIG1. ​​In the non-stretchable region of the stretchable device 1, both the stretchable cover layer 101 and the stretchable cover layer 102 may be present on the substrate 10, or only one of the stretchable cover layer 101 and the stretchable cover layer 102 may be present.

[0016] Referring also to FIG1, in some embodiments, the stretchable device 1 is a stretchable display panel, the electronic component 201 is a light-emitting diode 201, and the refractive index of the adhesive layer GL is greater than or equal to the refractive index of the stretchable cover layer 102, thereby preventing total internal reflection when the light generated by the light-emitting diode 201 enters the adhesive layer GL from the stretchable cover layer 102. In some embodiments, the refractive index of the stretchable cover layer 102 is greater than or equal to the refractive index of the stretchable cover layer 101, thereby preventing total internal reflection when the light generated by the light-emitting diode 201 enters the stretchable cover layer 102 from the stretchable cover layer 101.

[0017] Referring to FIG2, strain curves of multiple components in a stretchable device according to a comparative example and strain curves of multiple components in a stretchable device according to an embodiment of the present invention are shown. Both the stretchable device of the comparative example and the stretchable device of the present invention are stretchable display panels. Curves C1, C3, and C5 in FIG2 are strain curves of polymer traces, metal traces, and island structures in the stretchable device of the comparative example, respectively. Curves C2, C4, and C6 are strain curves of polymer traces, metal traces, and island structures in the stretchable device of the present invention, respectively. The stretchable device according to the comparative example only has a stretchable cover layer 101. The stretchable device according to the embodiment of the present invention has both a stretchable cover layer 101 and a stretchable cover layer 102, and has the structure shown in FIG1. ​​It can be seen that the strain curves of multiple components in the stretchable device according to the comparative example and the strain curves of multiple components in the stretchable device according to the embodiment of the present invention are consistent. That is, even with the stretchable cover layer 102 disposed on the stretchable cover layer 101, the stretchable device still possesses good tensile deformation capability.

[0018] In summary, in the stretchable device provided according to the embodiments of the present invention, a stretchable cover layer with a small elastic modulus and a stretchable cover layer with a large elastic modulus are sequentially arranged on the electronic structure layer. The former can avoid excessive stress on the electronic structure layer, and the latter can prevent the protective film to stick or the adhesive layer to break, thereby greatly improving the yield of the stretchable device, and the stretchable device can still have good tensile deformation capability. [Simplified Explanation of the Diagram]

[0019] FIG1 shows a schematic diagram of a stretchable device according to an embodiment of the present invention. FIG2 shows strain curves of multiple components in a stretchable device according to a comparative example and strain curves of multiple components in a stretchable device according to an embodiment of the present invention.

Claims

1. A stretchable device, comprising: One substrate; An electronic structure layer is disposed on the substrate; A first stretchable cover layer; And a second stretchable cover layer, wherein the first stretchable cover layer is located between the electronic structure layer and the second stretchable cover layer, wherein the elastic modulus of the second stretchable cover layer is greater than the elastic modulus of the first stretchable cover layer, and the stretchable device also satisfies the condition E2*H2>3*E1*H1, where H1 is the maximum thickness of the first stretchable cover layer in the normal direction of the substrate, H2 is the maximum thickness of the second stretchable cover layer in the normal direction, E1 is the elastic modulus of the first stretchable cover layer, and E2 is the elastic modulus of the second stretchable cover layer.

2. The stretchable device as claimed in claim 1, wherein the stretchable device has a stretchability of more than 5%.

3. The stretchable device as claimed in claim 1, wherein the first stretchable cover layer has a first maximum elongation, the second stretchable cover layer has a second maximum elongation, and the ratio of the second maximum elongation to the first maximum elongation is less than 0.

7.

4. The stretchable device as claimed in claim 1, wherein the first stretchable cover layer has an elongation in the range of 100% to 1500%.

5. The stretchable device as claimed in claim 1, wherein the elastic modulus of the second stretchable cover layer falls in the range of 30 MPa to 1 GPa.

6. The stretchable device as claimed in claim 1, wherein the elastic modulus of the first stretchable cover layer falls in the range of 1 MPa to 10 MPa.

7. The stretchable device as claimed in claim 1, further comprising an adhesive layer, wherein the second stretchable cover layer is located between the adhesive layer and the first stretchable cover layer.

8. The stretchable device as claimed in claim 1, further comprising a third stretchable cover layer and an adhesive layer, wherein the adhesive layer is located between the third stretchable cover layer and the second stretchable cover layer.

9. The stretchable device as claimed in claim 1, wherein the stretchable device is a stretchable display panel, and further includes a stretchable touch layer and an adhesive layer, wherein the adhesive layer is located between the stretchable touch layer and the second stretchable cover layer.

10. The stretchable device as claimed in claim 8 or 9, wherein the elastic modulus of the adhesive layer is less than the elastic modulus of the first stretchable cover layer.

11. The stretchable device as claimed in claim 8 or 9, wherein the elastic modulus of the adhesive layer falls in the range of 0.01 MPa to 1 MPa.

12. The stretchable device as claimed in claim 8 or 9, wherein the stretchable device is a stretchable display panel, and the refractive index of the adhesive layer is greater than or equal to the refractive index of the second stretchable cover layer.

13. The stretchable device as claimed in claim 12, wherein the refractive index of the second stretchable cover layer is greater than or equal to the refractive index of the first stretchable cover layer.

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