KR102406783B1 - Stretchable substrate and electronic device comprising the same - Google Patents

Abstract

The present application is a silicone-based adhesive layer; a non-stretchable pattern provided on one surface of the silicone-based adhesive layer; and a stretchable polymer film provided to bury the non-stretchable pattern on the surface of the silicone-based adhesive layer provided with the non-stretchable pattern, and an electronic device including the same.

Description

Stretchable substrate and electronic device including same

The present specification relates to a stretchable substrate and an electronic device including the same.

Conventionally, the display device includes an unbreakable display, a curved display, a bent display, a foldable display, and a rollable display. has been developed

Currently, the commercialization stage is about the mobile field in the form of a curved display, and it is expected that the mobile field using a foldable display will appear in earnest. In addition, the development speed of the electric field using pOLED is dazzling.

In particular, recently, according to the paradigm change of the display, a stretchable display that exceeds the characteristics of a display that can be wound has been developed, and a stretchable display needs to be easily stretched and contracted regardless of the direction. It is essential to develop a stretchable base material having high elongation and restoring force.

In the case of a stretchable display device including an electronic device, such as an organic light emitting device, since the electronic device does not include flexibility, a change in surface area due to stretching of the stretchable substrate may significantly reduce durability of the electronic device.

It is suggested that it can be applied to a display for medical purposes, starting with a touch screen panel as an application field of a stretchable display, and then as a wearable display using fiber. .

According to the above necessity, in forming the electronic device on the stretchable substrate, the durability of the electronic device can be maintained and there is a need to develop a stretchable substrate having excellent stretchability.

Japanese Patent Laid-Open No. 2006-299283

An object of the present specification is to provide a stretchable substrate and an electronic device including the same.

An exemplary embodiment of the present specification is a silicone-based adhesive layer; a non-stretchable pattern provided on one surface of the silicone-based adhesive layer; and a stretchable polymer film provided to embed the non-stretchable pattern on the surface of the silicone-based adhesive layer on which the non-stretchable pattern is provided.

In addition, an exemplary embodiment of the present application is a stretchable substrate according to an exemplary embodiment of the present application; and an electronic device provided on the adhesive layer of the stretchable substrate, wherein the electronic device is formed on a position where the non-stretchable pattern of the stretchable substrate is buried.

The stretchable substrate according to the exemplary embodiment of the present application is provided with a non-stretchable pattern having a structure recessed into the stretchable polymer film. It has a characteristic that the durability of the device is greatly improved.

In addition, the stretchable substrate according to the present application includes a stretchable polymer film and a silicone-based adhesive layer on the stretchable polymer film, and has excellent adhesion between the stretchable polymer film and the silicone-based adhesive layer even when stretching and shrinking several times is repeated, and later electronic devices stacking can be made stably, so that it is possible to prevent the problem of the electronic device detaching from the stretchable substrate during the post-process.

1 is a side view illustrating a stretchable substrate according to an exemplary embodiment of the present application.
2 is a top view illustrating a stretchable substrate according to an exemplary embodiment of the present application.
3 is a view showing a side view of a stretchable substrate according to an exemplary embodiment of the present application.
4 is a view showing an SEM image before stretching of the stretchable substrate according to Example 1 of the present application.
5 is a view showing an SEM image of the stretchable substrate according to Example 1 of the present application in a stretched state.
6 is a view showing an enlarged SEM image of the non-stretchable pattern in the stretched state of the stretchable substrate according to Example 1 of the present application.
7 is a diagram illustrating an enlarged SEM image of a non-stretchable pattern in a stretched state of a stretchable substrate according to Comparative Example 1 of the present application.

Hereinafter, the present specification will be described in more detail.

Embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those of ordinary skill in the art to which the present invention pertains can easily carry out the present invention. However, the present invention may be embodied in several different forms and is not limited to the embodiments described herein.

An exemplary embodiment of the present application is a silicone-based adhesive layer; a non-stretchable pattern provided on one surface of the silicone-based adhesive layer; and a stretchable polymer film provided to embed the non-stretchable pattern on the surface of the silicone-based adhesive layer on which the non-stretchable pattern is provided.

The stretchable substrate has a stretchable polymer film provided to embed the non-stretch pattern on the surface of the silicone-based adhesive layer provided with the non-stretch pattern, and as described in FIG. 1 , the non-stretch pattern is inserted into the stretchable polymer film It has a buried structure, and has a structure in which one surface of the non-stretchable pattern and one surface of the silicone-based adhesive layer are in contact.

In an exemplary embodiment of the present application, the Young's Modulus of the stretchable polymer film is G1, the Young's Modulus of the non-stretchable pattern is G2, and G1 and G2 satisfy the following Equations 1 to 3 It provides a stretchable substrate that is.

[Equation 1]

G1 ≤ 2 MPa

[Equation 2]

G2 ≥ 1000 MPa

[Equation 3]

G2/G1 ≥ 500

The Young's modulus of the stretchable polymer film and the non-stretchable pattern can be measured using Zwick/Roell's Z010 UTM equipment. Specifically, the stretchable polymer film and the non-stretchable material in the form of a film are 25±2° C., 50±5% Under RH (relative humidity), the Young's modulus can be obtained by measuring the stress/strain by fixing both ends in the longitudinal direction so that the width becomes 25mm and the length becomes 165mm, and then stretches it in the longitudinal direction at a speed of 100mm/min.

In the exemplary embodiment of the present application, Equation 1 may be G1 ≤ 2 MPa, preferably G1 ≤ 1.7 MPa, more preferably G1 ≤ 1.5 MPa.

In another exemplary embodiment, in Formula 1, G1 ≥ 0.01 MPa, preferably G1 ≥ 0.1 MPa, more preferably G1 ≥ 0.3 MPa.

In an exemplary embodiment of the present application, Equation 2 is G2 ≥ 1000 MPa, preferably G2 ≥ 2000 MPa, more preferably G2 ≥ 4000 MPa can be

In another exemplary embodiment, in Equation 2, G2 ≤ 10000 MPa, preferably G2 ≤ 9000 MPa, more preferably G2 ≤ 8000 MPa can be

In the exemplary embodiment of the present application, Equation 1 may be 0.01 MPa ≤ G1 ≤ 2 MPa, preferably 0.1 MPa ≤ G1 ≤ 1.7 MPa, more preferably 0.3 MPa ≤ G1 ≤ 1.5 MPa.

In an exemplary embodiment of the present application, Equation 2 may be 1000 MPa ≤ G2 ≤ 10000 MPa, preferably 2000 MPa ≤ G2 ≤ 8000 MPa, more preferably 4000 MPa ≤ G2 ≤ 8000 MPa.

As the stretchable substrate satisfies the ranges of Equations 1 and 2, when the stretchable substrate is uniaxially stretched, no separation occurs at the interface between the non-stretchable pattern and the stretchable polymer film, and accordingly, the durability of the electronic device in the future It is possible to have this excellent characteristic.

In an exemplary embodiment of the present application, Equation 3 satisfies G2/G1 ≥ 500, preferably G2/G1 ≥ 1000, and more preferably G2/G1 ≥ 3000.

In another exemplary embodiment, Equation 3 satisfies G2/G1 ≤ 60000, preferably G2/G1 ≤ 30000, and more preferably G2/G1 ≤ 20000.

In an exemplary embodiment of the present application, Equation 3 satisfies 500 ≤ G2/G1 ≤ 60000, preferably 2000 ≤ G2/G1 ≤ 30000, and more preferably 3000 ≤ G2/G1 ≤ 20000.

As the ratio of the stretchable polymer film to the non-stretchable pattern Young's modulus of the stretchable substrate satisfies the above range as shown in Equation 3, the stretchable substrate has excellent elongation and excellent durability.

In the exemplary embodiment of the present application, the non-stretchable pattern has a structure embedded in two or more island structures spaced apart by the stretchable polymer film, the line width of the non-stretchable pattern is D1, and the stretchable polymer film A distance between two adjacent non-stretchable patterns embedded in the is D2, and D1 and D2 satisfy Equations 4 and 5 below.

[Equation 4]

30μm ≤ D1 ≤ 1000μm

[Equation 5]

D1/D2 ≤ 4

The fact that the non-stretch pattern has a structure buried in two or more island structures spaced apart from the stretchable polymer film means that the non-stretch pattern has a structure in which the non-stretch pattern is embedded at regular intervals, or that the non-stretch pattern is embedded at irregular intervals. All structures can be included.

In the present application, the meaning of adjacent means that it is adjacent to or closest to the target configuration, and specifically, that the non-stretchable pattern embedded in the stretchable polymer film is adjacent means that it is adjacent to a specific one ratio. Based on the elastic pattern, it means that the distance between the center of the specific non-stretch pattern and the center of the adjacent non-stretch pattern is the closest. The central portion of the pattern means a central portion on one surface of the pattern.

1 is a side view of a stretchable substrate according to an exemplary embodiment of the present application, and a buried structure of a non-stretchable pattern can be confirmed.

2 is a top view of a stretchable substrate according to an exemplary embodiment of the present application. Specifically, a line width 100 of a non-stretchable pattern and a distance 200 between adjacent non-stretchable patterns can be confirmed.

In the exemplary embodiment of the present application, the non-stretchable pattern may have a polygonal cross-section in the line width direction of the non-stretchable pattern.

In the exemplary embodiment of the present application, the non-stretchable pattern may have a cross-section in the line width direction of the non-stretchable pattern selected from the group consisting of a circle, a triangle, a quadrangle, a pentagon, and a hexagon.

In another exemplary embodiment, the non-stretchable pattern may have a quadrangular cross-section in the line width direction of the non-stretchable pattern.

In an exemplary embodiment of the present application, Equation 4 may be 30 μm ≤ D1 ≤ 1000 μm, preferably 30 μm ≤ D1 ≤ 500 μm, and more preferably 30 μm ≤ D1 ≤ 100 μm.

In the exemplary embodiment of the present application, Equation 5 may be D1/D2 ≤ 4, preferably D1/D2 ≤ 2, more preferably D1/D2 ≤ 1.

In another exemplary embodiment, in Equation 5, D1/D2 ≥ 0.1, preferably D1/D2 ≥ 0.5, more preferably D1/D2 ≥ 0.8.

In an exemplary embodiment of the present application, the D2 may be 30 μm ≤ D2 ≤ 500 μm, preferably 55 μm ≤ D2 ≤ 300 μm, more preferably 65 μm ≤ D2 ≤ 100 μm.

As the stretchable substrate according to the present application satisfies the ranges of Equations 4 and 5, there is no gap between the non-stretchable pattern and the stretchable polymer film when the stretchable substrate of the present application is stretched, and the stretchability and hardness are satisfied. It has the characteristics of being able to manufacture a substrate.

In an exemplary embodiment of the present application, the line height of the non-stretchable pattern may be 5 μm or more and 100 μm or less.

The line height of the non-stretch pattern means a height in a direction perpendicular to the line width direction of the non-stretch pattern. Specifically, the line 300 of the non-stretch pattern can be confirmed in FIG. 3 .

In another exemplary embodiment, the line height of the non-stretch pattern may be 5 μm or more and 100 μm or less, preferably 10 μm or more and 100 μm or less, and more preferably 10 μm or more and 50 μm or less.

When the height of the non-stretchable pattern satisfies the above range, the electronic device is not deformed when the electronic device is subsequently stacked, and the distance between the non-stretchable pattern and the stretchable polymer film does not occur, so that the durability of the electronic device is improved. It has good characteristics.

In the exemplary embodiment of the present application, the non-stretchable pattern can be used without particular limitation as long as it satisfies the Young's modulus of Equation 2, and is a photo-curable polymer material, specifically, a dry film resist for forming an electronic circuit board, a column spacer It may be selected from the group consisting of a photosensitive resin composition and a photosensitive resin composition for forming an organic insulating pattern.

In an exemplary embodiment of the present application, there is provided a stretchable substrate of polydimethylsiloxane (PDMS) having an elongation at break of 100% or more of the stretchable polymer film.

In another exemplary embodiment, the elongation at break of the stretchable polymer film may be 100% or more, preferably 110% or more, and more preferably 130% or more.

In another exemplary embodiment, the elongation of the stretchable polymer film may be 180% or less, preferably 170% or less.

The elongation at break of the stretchable polymer film means (L2-L1)/L1*100 (%) when the initial length of the stretchable polymer film is L1 and the length at which breakage occurs by stretching it is L2.

As the elongation rate of the stretchable polymer film satisfies the above range, the elongation rate of the stretchable substrate having a structure in which the non-stretchable pattern is embedded later has a characteristic that can satisfy a specific range, and the stretchable polymer film in the manufacturing process of the stretchable substrate As the elongation rate of is within the above range, handling is easy.

In an exemplary embodiment of the present application, the stretchable polymer film may be used without particular limitation as long as it satisfies the Young's modulus of Formula 1, and a polydimethylsiloxane polymer material may be used, specifically, a condensation polymerization type polydimethylsiloxane; It may be selected from the group consisting of addition polymerization type polydimethylsiloxane and radical polymerization type polydimethylsiloxane.

In an exemplary embodiment of the present application, the stretchable polymer film may be polydimethylsiloxane.

In an exemplary embodiment of the present application, the silicone-based adhesive layer includes polyorganosiloxane and a curing catalyst.

In the case of the silicon-based adhesive layer, the surface exposed on the upper portion of the stretchable substrate and components and contents included in the silicon-based adhesive layer in the stretchable substrate may be confirmed by Nuclear Magnetic Resonance (NMR) analysis.

In the exemplary embodiment of the present application, the silicone-based adhesive layer may be formed by drying the silicone-based adhesive layer composition.

In the exemplary embodiment of the present application, the silicone-based adhesive layer may be formed by curing the silicone-based adhesive layer composition.

In an exemplary embodiment of the present application, the silicone-based adhesive layer composition may include polyorganosiloxane; curing catalyst; and solvents.

In an exemplary embodiment of the present application, the solvent is not limited as long as it can dissolve the silicone-based adhesive layer composition, and specifically, an organic solvent may be used, and more specifically, toluene may be used.

In an exemplary embodiment of the present application, the polyorganosiloxane may be included in an amount of 40 to 70 parts by weight, preferably 45 to 60 parts by weight, more preferably 45 to 55 parts by weight based on 100 parts by weight of the silicone-based adhesive layer composition. have.

In an exemplary embodiment of the present application, the curing catalyst may be included in an amount of 0.1 to 2 parts by weight, preferably 0.2 to 1 parts by weight, more preferably 0.3 to 0.8 parts by weight, based on 100 parts by weight of the silicone-based adhesive layer composition.

In the exemplary embodiment of the present application, the solvent may be included in an amount of 40 to 70 parts by weight, preferably 45 to 60 parts by weight, more preferably 45 to 55 parts by weight based on 100 parts by weight of the silicone-based adhesive layer composition.

Since the stretchable substrate according to the present application has a silicone-based adhesive layer, the adhesive force between the silicone-based adhesive layer and the stretchable polymer film made of polydimethylsiloxane is particularly excellent, and the adhesive force can be maintained even after repeated stretching and contraction, and the silicone-based adhesive layer In addition, since the elongation rate is excellent, it has excellent properties to be applied to a stretchable substrate.

In an exemplary embodiment of the present application, after bonding the opposite side of the surface of the silicone-based adhesive layer in contact with the stretchable polymer film to a polyimide film (PI, Polyimide), the adhesive strength after standing at 23° C., 50 RH% for 1 hour It can be more than 300 gf/inch.

In another exemplary embodiment, after bonding the opposite surface of the surface in contact with the stretchable polymer film of the silicone-based adhesive layer to a polyimide film (PI, Polyimide), the adhesive strength after standing at 23° C., 50 RH% for 1 hour is 300 gf/inch or more, preferably 350 gf/inch or more, more preferably 450 gf/inch or more, and 1000 gf/inch or less, preferably 850 gf/inch or less.

When the adhesive force of the silicone-based adhesive layer to a polyimide film (PI, Polyimide) opposite to the surface in contact with the stretchable polymer film of the silicone-based adhesive layer satisfies the above conditions and ranges, an electronic device is later disposed on the silicone-based adhesive layer, the electronic device Since the stacking can be made stably, it is possible to prevent the problem of the electronic device being detached from the stretchable substrate during a post process.

In an exemplary embodiment of the present application, with respect to the surface in which the stretchable polymer film and the silicone-based adhesive layer are in contact, the adhesive strength is 300 gf/ It provides a stretchable substrate that is more than an inch.

In another exemplary embodiment, with respect to the surface in which the stretchable polymer film and the silicone-based adhesive layer are in contact, the adhesive strength is 300 gf/inch after bonding the stretchable polymer film and the silicone-based adhesive layer and standing at 23° C. and 50 RH% for 1 hour or more, preferably 350 gf/inch or more, and more preferably 400 gf/inch or more.

In another exemplary embodiment, with respect to the surface in which the stretchable polymer film and the silicone-based adhesive layer are in contact, the adhesive force is 900 gf/inch after bonding the stretchable polymer film and the silicone-based adhesive layer and leaving it at 23° C. and 50 RH% for 1 hour or less, preferably 850 gf/inch or less, and more preferably 800 gf/inch or less.

As the adhesive force between the contact surface of the stretchable polymer film and the silicone adhesive layer satisfies the above range, the electronic device can be stably bonded in the future, and even after repeated stretching and contraction several times, the silicone adhesive layer and the stretchable polymer film It has the characteristics of being able to manufacture a stretchable substrate with excellent durability and stability because the interface does not float, and it has a characteristic that there is no separation from the non-stretchable pattern embedded in the stretchable polymer film.

In the present application, the adhesive strength is measured after forming the silicone-based adhesive layer to a thickness of 20 μm on a glass substrate, and then laminating a stretchable polymer film or polyimide film on the surface of the silicone-based adhesive layer of the glass substrate provided with the silicone-based adhesive layer 23 After standing at ℃, 50 RH% for 1 hour, the adhesive strength can be measured while peeling the stretchable polymer film or polyimide film from the adhesive layer at an angle of 90°. (Stable Micro Systems' Texture Analyzer)

In an exemplary embodiment of the present application, the thickness of the silicone-based adhesive layer may be 5 μm or more and 30 μm or less.

In another exemplary embodiment, the thickness of the silicone-based adhesive layer may be 5 μm or more and 30 μm or less, preferably 10 μm or more and 25 μm or less, and more preferably 15 μm or more and 25 μm or less.

In an exemplary embodiment of the present application, the thickness of the stretchable polymer film may be 100 μm or more and 1000 μm or less.

In another exemplary embodiment, the thickness of the stretchable polymer film may be 100 μm or more and 1000 μm or less, preferably 100 μm or more and 700 μm or less, and more preferably 200 μm or more and 500 μm or less.

As the silicone-based adhesive layer and the stretchable polymer film satisfy the thickness range, the stretchability of the stretchable substrate of the present application is excellent, and the adhesive strength between the stretchable polymer film and the silicone-based adhesive layer is particularly excellent. It has a property that the silicone-based adhesive layer and the stretchable polymer film do not break with respect to the stretching force.

3 is a side view of the stretchable substrate of the present application, and the thickness 400 of the stretchable polymer film and the thickness of the silicone-based adhesive layer 500 can be confirmed. That is, the thickness of the stretchable polymer film and the thickness of the silicone-based adhesive layer mean the thickness in the stacking direction on the stretchable substrate.

In an exemplary embodiment of the present application, an elongation of the stretchable substrate may be 20% or more.

In another exemplary embodiment, the stretchable substrate may have an elongation of 20% or more, preferably 35% or more, more preferably 50% or more, and may satisfy a range of 150% or less, preferably 130% or less. have.

The elongation of the stretchable substrate means the maximum elongation at which no separation occurs between the stretchable polymer film and the non-stretchable pattern, and the occurrence of the separation between the stretchable polymer film and the non-stretchable pattern indicates that lifting occurs. A specific SEM image of the occurrence of separation in Fig. 6 can be confirmed.

That is, in the present application, in the elongation rate of the stretchable substrate, the spacing occurs according to the line width (D1) of the non-stretchable pattern and the distance (D2) between adjacent non-stretchable patterns recessed on one surface of the inside of the stretchable polymer film. It means the maximum elongation rate not to do this, and when the stretchable substrate according to the present application satisfies the conditions of Equations 4 and 5, it may mean the maximum elongation rate at which the separation does not occur.

The elongation rate of the stretchable substrate is that the stretchable substrate having a size of 1.5 cm * 5 cm is stretched left and right in the long axis direction, and the elongation rate at the time when the separation occurs at the boundary between the non-stretchable pattern and the stretchable polymer film can be measured.

After all, in the case of the stretchable substrate, the silicone-based adhesive layer and the non-stretchable pattern are embedded in the stretchable polymer film, and even when the stretch rate of the stretchable substrate is within the above range, there is no gap between the non-stretchable pattern and the stretchable polymer film. A stretchable substrate can be manufactured.

In the exemplary embodiment of the present application, a release film may be further included on the opposite side of the surface of the silicone-based adhesive layer in contact with the stretchable polymer film.

The release film is a layer for protecting a very thin silicone adhesive layer, refers to a transparent layer attached to one surface of the silicone adhesive layer, and a film excellent in mechanical strength, thermal stability, moisture shielding property, isotropy, etc. can be used. For example, acetate-based, polyester-based, polyethersulfone-based, polycarbonate-based, polyamide-based, polyimide-based, polyolefin-based, cycloolefin-based, polyurethane-based and acrylic resin films such as triacetylcellulose (TAC) can be used, but is not limited thereto if it is a commercially available fluorine-treated release film.

In an exemplary embodiment of the present application, the stretchable substrate according to the present application; and an electronic device provided on the adhesive layer of the stretchable substrate, wherein the electronic device is formed on a position where the non-stretchable pattern of the stretchable substrate is buried.

In an exemplary embodiment of the present application, the electronic device may be a display device, a touch panel, or a semiconductor panel.

In an exemplary embodiment of the present application, the electronic device provides an electronic device selected from the group consisting of an organic photoelectric device, an organic transistor, an organic solar cell, a micro LED device, and an organic light emitting device.

When the electronic device according to the present application is used in a display device, it may include a stretchable display, and as the electronic device is formed on a position where the non-stretchable pattern of the stretchable substrate is embedded, stretching and original restoration are repeated. Even so, it is possible to minimize the application of external force to the electronic device itself, and thus, it is possible to provide a display device having excellent extensibility and excellent durability.

In particular, since the stretchable substrate according to the present application includes a silicon-based adhesive layer, electronic devices can be stably disposed on the stretchable substrate even after repeated stretching and original restoration.

A stretchable substrate according to an exemplary embodiment of the present application includes the steps of preparing a copper foil; Laminating a protective film on one side of the copper foil; forming a non-stretchable pattern on the opposite side of the side on which the protective film of the copper foil is laminated; applying a stretchable polymer film on the copper foil on which the non-stretch pattern is formed; removing the protective film and the copper foil; It may be manufactured according to the step of forming a silicone-based adhesive layer on the non-stretchable patterned surface of the stretchable polymer film.

The protective film may include a base film and a pressure-sensitive adhesive layer provided on one surface of the base film.

The pressure-sensitive adhesive layer is used for bonding the base film and the copper foil, and is not limited thereto, and a commercially available adhesive layer may be used if there is an adhesive force.

The base film is not limited as long as it can prevent damage to the copper foil during the process, but PET (polyethylene terephthalate), polyester, PC (polycarbonate), PI (polyimide), PEN (polyethylene naphthalate), PEEK ( It may be selected from the group consisting of polyether ether ketone), polyarylate (PAR), polycylicolefin (PCO), polynorbornene, polyethersulphone (PES), and cycloolefin polymer (COP).

In the exemplary embodiment of the present application, the forming of the non-stretchable pattern may be formed using a photolithography process.

In an exemplary embodiment of the present application, the protective film and the copper foil may be removed after the step of applying the stretchable polymer film.

In an exemplary embodiment of the present application, the copper foil may be removed using an etchant, and the etchant may be an iron chloride-based copper etchant.

In an exemplary embodiment of the present application, the step of forming a silicone-based adhesive layer on the non-stretchable pattern-equipped surface of the stretchable polymer film includes: preparing a fluorine-based release film; applying the silicone-based adhesive layer composition on the fluorine-based release film; and curing the silicone-based adhesive layer composition.

The fluorine-based release film is the same as the description of the release film described above.

In the case of the silicone-based adhesive layer composition, before the silicone-based adhesive layer is cured, a solvent may be included in the aforementioned silicone-based adhesive layer.

Hereinafter, the present specification will be described in more detail through examples. However, the following examples are only for illustrating the present specification, and not for limiting the present specification.

< production example >

[ Example 1]- Fabrication of stretchable substrate

A copper foil having a thickness of 10 μm with a protective film laminated on one side was prepared. After laminating 10㎛ TPF (Transparent Photosensitive Film, Hitachi Chemical) as a photocurable polymer material on the copper foil, the non-stretchable pattern line width is 82㎛ and the distance between the non-stretchable patterns is 85㎛ through a photo process. An elastic pattern was formed. KE-441K-T (Shinetsu Corporation) as a polydimethylsiloxane material was applied to the upper portion of the laminate provided with the non-stretch pattern to a thickness of 300 μm, cured at room temperature for 24 hours, and then additionally heat treated at 100° C. for 1 hour. After removing the protective film from the laminate provided with the polydimethylsiloxane polymer layer, the exposed copper foil was removed using a ferric chloride-based copper etchant to prepare a stretchable polymer film having a non-stretchable pattern embedded therein.

As a silicone adhesive composition, 50 parts by weight of organopolysiloxane of KR-3700 (Shinetsu), 0.5 parts by weight of CAT-PL-50T as a curing catalyst, and 49.5 parts by weight of toluene as a diluting solvent were mixed, and then a bar coating method was applied on the fluorine-based release film. After coating using a sieve, it was dried at 100° C. for 20 minutes to form a silicone-based adhesive layer having a thickness of 20 μm.

After laminating so that the non-stretchable pattern exposed side of the stretchable polymer film in which the non-stretchable pattern is embedded and the silicone-based adhesive layer side of the fluorine-based release film provided with the silicone-based adhesive layer correspond to each other, at 23°C, 50 RH% for 1 hour was left

[ Example 2]

A stretchable substrate was manufactured in the same manner as in Example 1, except that KE-4896 (Shinetus) was applied as a polydimethylsiloxane material in Example 1.

[ comparative example One]

In Example 1, KE-106 (Shinetsu) was applied as a polydimethylsiloxane material instead of KE-441K-T (Shinetsu) as the polydimethylsiloxane material, and an epoxy-based adhesive with a thickness of 25 μm was applied instead of a silicone-based adhesive layer. , to prepare a stretchable substrate in the same manner as prepared in Example 1.

As the epoxy-based adhesive composition, 33 wt% of silane-modified epoxy resin KSR-277HMC70 (Kukdo Chemical), 35 wt% of silane-modified epoxy resin KSR-177 (Kukdo Chemical), 30 wt% of bisphenol A phenoxy resin YP-50E (Kukdo Chemical) % by weight, 1% by weight of thermosetting agent 2P4MHZ (SHIKOKU), and 1% by weight of silane coupling agent KBM-403 (Shinetsu).

[ comparative example 2]

In Example 1, a stretchable substrate was manufactured in the same manner as in Example 1, except that Optically Clear Adhesive (3M), an acrylic adhesive having a thickness of 25 μm, was applied instead of the silicone adhesive layer.

The physical properties and properties of the stretchable polymer films according to Examples 1 and 2, Comparative Examples 1 and 2 are shown in Table 1 below.

Example 1 Example 2 Comparative Example 1 Comparative Example 2 Modulus (MPa) of stretchable polymer film, G1 0.43 1.31 2.52 0.43 Modulus (MPa) of non-stretch pattern, G2 4800 4800 4800 4800 G2/G1 111,627 3,664 1,905 111,627 Non-stretch pattern line width (㎛), D1 82 82 82 82 Distance between non-stretch patterns (㎛), D2 85 85 85 85 D1/D2 0.96 0.96 0.96 0.96 Non-stretch pattern line (㎛) 10 10 10 10 Elongation at break of stretchable polymer film (%) 280 170 100 280 Adhesion between the adhesive layer and the stretchable polymer film (gf/in) 500 gf/in or more 500 gf/in or more less than 100 gf/in less than 100 gf/in Adhesion between adhesive layer and polyimide film (gf/in) 500 gf/in or more 500 gf/in or more 500 gf/in or more 500 gf/in or more Elongation Durability (%) over 100 50 or more less than 20 over 100

1) Modulus measurement: The stretchable polymer film and the non-stretchable material in the form of a film were measured using Zwick/Roell's Z010 UTM equipment, respectively. Specifically, the stretchable polymer film and the non-stretchable material in the form of a film were measured at 25±2℃, 50 Under ±5% RH (relative humidity), both ends in the longitudinal direction were fixed so that the width became 25 mm and the length was 165 mm, and then the stress/strain was measured by stretching it in both directions in the longitudinal direction at a speed of 100 mm/min.

2) Method of measuring adhesive strength of adhesive layer: An adhesive layer is formed to a thickness of 20 μm on a glass substrate. After laminating a stretchable polymer film or polyimide film on the adhesive layer side of the glass substrate provided with the adhesive layer, it was left at 23° C. and 50 RH% for 1 hour, and then the stretchable polymer film or polyimide film was applied to the adhesive layer at a 90° angle Adhesion was measured while peeling (Stable Micro Systems' Texture Analyzer).

3) Stretching durability evaluation: A stretchable substrate having a size of 1.5cm * 5cm was stretched left and right in the long axis direction, and the elongation rate at which a gap occurred at the boundary between the non-stretchable pattern and the stretchable polymer film was measured.

As can be seen from Table 2, it was confirmed that the stretchable substrates (Examples 1 and 2) according to the present application had a stretch durability of 20 or more as the above modulus and conditions were satisfied. If the stretch durability has a value of 20 or more, it means that a separation between the non-stretchable pattern and the stretchable polymer film does not occur even when a strong external force is applied, and it was confirmed that the stretchable substrate according to the present application has very excellent durability.

In addition, since the stretchable substrate according to the present application uses a silicone-based adhesive layer, the adhesive strength between the silicone-based adhesive layer and the stretchable polymer film and the adhesive strength between the silicone-based adhesive layer and the polyimide film are excellent. It was confirmed that the electronic device could be stably disposed in the region corresponding to the stretchable pattern.

Specifically, FIG. 4 is a view of an SEM photograph before stretching the stretchable substrate according to Example 1 of the present application, and FIG. 5 is a view showing an SEM image in a state in which the stretchable substrate according to Example 1 of the present application is stretched by 30%. , FIG. 6 shows an enlarged SEM image of one non-stretchable pattern in the stretchable substrate according to Example 1 of the present application.

As can be seen in FIGS. 4 to 6 , in the case of the stretchable substrate according to the present application, it was confirmed that there was no gap between the non-stretchable pattern and the stretchable polymer film even when stretching/recovering according to a strong external force was repeated.

In the case of Comparative Examples 1 and 2, when the silicone-based adhesive layer was not used as the adhesive layer of the stretchable substrate, and the adhesive layer and the stretchable polymer film were formed to have low adhesion and repeated stretching/returning several times, the adhesive layer and the stretchable polymer It was confirmed that the interface of the film was lifted, and thus the durability of the electronic device deteriorated. In particular, in Comparative Example 1, when the modulus value of the stretchable polymer film exceeded 2 MPa, it was confirmed that the elongation durability was very poor. could

7 shows an enlarged SEM image of one non-stretchable pattern in the stretchable substrate according to Comparative Example 1 of the present application. As can be seen in FIG. 6 , when the elongation/recovery evaluation is performed with the same external force as in Example 1, it can be confirmed that a gap has occurred between the non-stretchable pattern and the stretchable polymer film, and such a stretchable substrate has poor durability. could confirm that it was not.

1: Stretchable polymer film
2: Non-stretch pattern
3: silicone adhesive layer
100: line width of non-stretch pattern
200: distance between adjacent non-stretch patterns
300: sentence of inelastic pattern
400: the thickness of the stretchable polymer film
500: the thickness of the silicone-based adhesive layer

Claims (13)

silicone-based adhesive layer;
a non-stretchable pattern provided on one surface of the silicone-based adhesive layer; and
a stretchable polymer film provided to embed the non-stretchable pattern on the surface of the silicone-based adhesive layer provided with the non-stretchable pattern;
including,
The Young's Modulus of the stretchable polymer film is G1,
The Young's Modulus of the non-stretchable pattern is G2,
Wherein G1 and G2 satisfy the following formulas 1 to 3,
[Equation 1]
G1 ≤ 2 MPa
[Equation 2]
G2 ≥ 1000 MPa
[Equation 3]
G2/G1 ≥ 500
The non-stretchable pattern includes a photocurable polymer material,
The silicon-based adhesive layer has a thickness of 5 μm or more and 30 μm or less. delete The method according to claim 1,
The non-stretchable pattern has a structure embedded in two or more island structures spaced apart by the stretchable polymer film,
The line width of the non-stretchable pattern is D1,
A distance between two adjacent non-stretchable patterns embedded in the stretchable polymer film is D2,
Wherein D1 and D2 is a stretchable substrate that satisfies Equations 4 and 5 below:
[Equation 4]
30μm ≤ D1 ≤ 1000μm
[Equation 5]
D1/D2 ≤ 4. The method according to claim 1,
The line height of the non-stretchable pattern is 5 μm or more and 100 μm or less. The method according to claim 1,
The stretchable substrate of polydimethylsiloxane (PDMS) having an elongation at break of 100% or more of the stretchable polymer film. The method according to claim 1,
After bonding the opposite side of the silicone-based adhesive layer to the surface in contact with the stretchable polymer film to a polyimide film (PI, Polyimide), the adhesive strength after standing at 23° C. and 50 RH% for 1 hour is 300 gf/inch or more. The stretchable substrate . The method according to claim 1,
With respect to the surface in contact with the elastic polymer film and the silicone-based adhesive layer,
After bonding the stretchable polymer film and the silicone-based adhesive layer, the adhesive strength after standing at 23° C. and 50 RH% for 1 hour is 300 gf/inch or more. delete The method according to claim 1,
The stretchable substrate has a thickness of 100 μm or more and 1000 μm or less of the stretchable polymer film. The method according to claim 1,
A stretchable substrate comprising a release film on a surface opposite to the surface of the silicone-based adhesive layer in contact with the stretchable polymer film. The method according to claim 1,
The stretchable substrate having an elongation of 20% or more of the stretchable substrate. The stretchable substrate according to any one of claims 1, 3 to 7, and 9 to 11; and
an electronic device provided on the adhesive layer of the stretchable substrate;
An electronic device comprising:
and the electronic device is formed on a position where the non-stretchable pattern of the stretchable substrate is buried. 13. The method of claim 12,
The electronic device is
An electronic device selected from the group consisting of an organic photoelectric device, an organic transistor, an organic solar cell, a micro LED device, and an organic light emitting device.

Images