KR102375799B1 - Method for implementing instantaneous strain reversibility to stretchable/flexible adhesives using pre-straining strategy - Google Patents

Abstract

The present invention relates to a method for imparting immediate strain recovery of an adhesive using a pre-strain strategy, specifically comprising the step of pre-straining a laminate including pressure sensitive adhesives (PSA) , to a method for providing immediate deformation recovery properties of the pressure-sensitive adhesive. In the method for imparting immediate deformation recovery of the pressure-sensitive adhesive according to the present invention, when the laminate prepared from the pressure-sensitive adhesive composition is pre-strained by 5 to 15%, the pre-strained laminate has a strain of 15% or less It was confirmed that an immediate shape recovery to the original state is possible from the (strain) change.

Description

Method for imparting immediate deformation recovery of an adhesive using a pre-strain strategy

The present invention relates to a method for imparting immediate strain recovery properties of an adhesive using a pre-strain strategy, and more particularly, to a method comprising pre-straining a laminate including a pressure sensitive adhesive (PSA) , to a method for providing immediate deformation recovery properties of the pressure-sensitive adhesive.

Since humans and devices can send and receive feedback and responses through displays, displays play an important role in communication between humans and devices in the present age.

The display has changed from a rigid and plate-shaped design to a flexible and curved design, and with the advent of epidermal electronics with a health care system, the development of a stretchable and flexible display is required. come. Therefore, it is important to develop an adhesive having a performance compatible with a stretchable/flexible device.

PSAs (pressure sensitive adhesives) are flexible adhesives that can form a bond with an adhesive under low pressure and do not leave any residue when removed. In addition, there is an effect of increasing the light transmittance by removing the air layer as well as the role of an adhesive that attaches between the display components.

However, due to the inherent flexibility of PSAs, there is a limit to the application of stretchable devices. This is because, although stretchable devices require immediate recovery of shape (loading -> unloading), partial recovery is possible with the flexible adhesive itself, but immediate recovery is limited.

In addition, there is a possibility of substrate corrosion due to the acrylic acid monomer used to increase the adhesiveness, and if the stress applied to the adhesive continues when the stretchable/flexible device is deformed, delamination between the adhesive and the component may occur. can be Therefore, in order to solve this problem, stress relaxation of the pressure-sensitive adhesive is required.

Republic of Korea Patent Registration No. 10-2128459

The present invention provides a method for imparting immediate deformation recovery of an adhesive through the step of pre-straining a laminate including pressure sensitive adhesives (PSA), the method of the present invention is a stretchable /Compatible with flexible electronic devices, and immediate recovery of the deformed adhesive is possible through the strategy of pre-strain.

In one embodiment of the present invention, there is provided a method for imparting immediate strain recovery of an adhesive, comprising the step of pre-straining a laminate including pressure sensitive adhesives (PSA).

The laminate is pre-strained through a mechanism that provides expansion to the laminate along one or more axes. Pre-strain can be provided, for example, by stretching the laminate along a first axis. Optionally, the stack may extend along multiple axes, for example along first and second axes positioned perpendicular to each other.

Means for pre-straining the laminate through a mechanism that provides stretching of the laminate may include bending, rolling, flexing, flattening, expanding or otherwise modifying the laminate. including transforming. The means for pre-straining also include pre-straining provided by raising the temperature of the laminate, thereby providing thermal expansion of the laminate.

Referring to the figure below, pre-strain means extending the laminate from its original length (L _o ) to its initial length (L _i ).

As used herein, “immediate recovery from deformation” refers to a pressure-sensitive adhesive or a laminate including the pressure-sensitive adhesive, which is stretched or deformed in one or more directions by a physical force, and its shape without substantial permanent deformation when the physical force is removed. It refers to a property that can be immediately restored to its original state. Referring to the figure above, when a deformation (S _x ) is applied by a physical force to a laminate ( _Li ) manufactured by applying a pre-strain (S _p ), after the physical force is removed, the The laminate is immediately restored to its original length (L _i ) and exhibits an elastic body-like behavior.

The pressure-sensitive adhesive is not particularly limited as long as it is used for an adhesive sheet, an adhesive film, or the like. For example, there are acrylic, urethane, polyisobutylene, SBR (styrene-butadiene rubber), rubber, polyvinyl ether, epoxy, melamine, polyester, phenol, silicone, or copolymers thereof. , particularly preferably an acrylic pressure-sensitive adhesive.

In the laminate, the base film is laminated by the pressure-sensitive adhesive, and the type of the base film is not particularly limited.

As the base film, a material of a known base film may be used without any particular limitation. For example, an inorganic film or plastic film such as a glass film, a crystalline or amorphous silicon film, a quartz or indium tin oxide (ITO) film may be used, and a plastic film may be used in terms of implementing a flexible device.

Examples of the plastic film include triacetyl cellulose (TAC); COP (cyclo olefin copolymer) such as norbornene derivatives; PMMA(poly(methyl methacrylate); PC(polycarbonate); PE(polyethylene); PP(polypropylene); PVA(polyvinyl alcohol); DAC(diacetyl cellulose); Pac(Polyacrylate); PES(poly ether sulfone); PEEK(polyetheretherketon) ); PPS (polyphenylsulfone), PEI (polyetherimide); PEN (polyethylenemaphthatlate); PET (polyethyleneterephtalate); PI (polyimide); PSF (polysulfone); No. A coating layer of a silicon compound such as gold, silver, silicon dioxide or silicon monoxide, or a coating layer such as an antireflection layer may be present on one surface of the base film if necessary.

Moreover, a translucent film can be used as a base film. For example, it may refer to a film having a transmittance of 50% or more, 60% or more, 70% or more, or 80% or more with respect to any one light in the visible light region or light in the entire visible light region. Depending on the structure of the flexible device to be applied, a film other than the light-transmitting film may be used as the base film. In addition, if necessary, a reflective layer may be formed on the surface of the film by using a reflective material such as aluminum. The base film may be a TFT base film in which a driving TFT (Thin Film Transistor) exists.

In a specific embodiment, it is preferable that the pre-strain step pre-strain the laminate by 5 to 15% from its original length. When the laminate is pre-strained to less than 5%, it is confirmed that the shape of the laminate is not immediately recovered, and a recovery time of about 5-10 seconds is required to recover the laminate to its original shape after 100 cycles of repeated 15% strain. became In addition, when the pre-strain exceeds 15%, there is a disadvantage in that the strain that can actually give the deformation is reduced.

When 5 to 15% pre-strain is applied after manufacturing the laminate, the pre-strained laminate can immediately recover its shape to its original state at a strain change of 15% or less. confirmed to be

According to another embodiment of the present invention, the method may further include manufacturing the laminate before the step of pre-straining the laminate.

Preparing the laminate may include applying a pressure-sensitive adhesive composition on a base film and laminating another base film, and may further include curing the pressure-sensitive adhesive composition after the laminating step. .

The pressure-sensitive adhesive composition is preferably applied to a thickness of 0.05 to 0.5mm.

The curing step of the pressure-sensitive adhesive composition may include UV curing or heat curing, and may be applied differently depending on the type of pressure-sensitive adhesive used. Preferably in the UV curing step, it can be exposed to UV for 10 seconds to 1 minute after lamination.

UV curing step may be exposed to UV for 10 seconds to 1 minute after lamination of the base film. Similarly, if the UV curing step proceeds for less than 10 seconds, there may be difficulties in curing, and if it exceeds 1 minute, the pressure-sensitive adhesive composition may be cured a lot, so that the instantaneous recovery from deformation of the present invention may not appear. However, the UV curing time is not limited thereto, and may vary depending on the type and composition of the pressure-sensitive adhesive.

The UV curing step is a polymerization reaction induced by light irradiation. In the polymerization type, a third-party molecule that coexists with non-sensitization polymerization, which reacts by increasing the energy level of electrons by absorbing light directly into the compound It refers to both of sensitization polymerization that absorbs light and causes a reaction by transferring its energy.

Conventionally, a pressure-sensitive adhesive composition was coated on one side of a release film and UV irradiated to carry out a photopolymerization reaction. In this reaction, oxygen as a radical scavenger (radical scavenger) can terminate the radical reaction, so the reaction must be carried out under nitrogen conditions without oxygen.

Therefore, in the conventional PSAs manufacturing process, nitrogen was continuously supplied to create an oxygen-free state, and polymer polymerization was performed. That is, in the prior art, in order to block the contact of oxygen, the reaction was carried out in a nitrogen environment, and the reaction was carried out in an environment capable of blocking the supply of nitrogen and the inflow of oxygen for polymer polymerization.

On the other hand, in the case of the present invention, in order to prevent such inconvenience, a laminate form is made by placing the first and second base films in a double layer above and below the pressure-sensitive adhesive composition to form a laminate during photopolymerization. It can block contact with oxygen.

That is, not by artificially supplying nitrogen to block the contact of oxygen, but by using a double-layer method of locating a release film on the upper and lower surfaces of the pressure-sensitive adhesive composition, the pressure-sensitive adhesive composition with oxygen in the UV irradiation step It prevents the possibility of contact and can proceed with a radical reaction.

As the contact with oxygen is blocked, the radical reaction of the monomers in the pressure-sensitive adhesive composition may proceed smoothly.

According to another embodiment of the present invention, the pressure-sensitive adhesive composition is an acrylate-based compound; crosslinking agent; photoinitiators; Fillers and dispersants may be included.

The pressure-sensitive adhesive composition may include an acrylate-based compound; crosslinking agent; photoinitiators; and a dispersing agent, and mixing the hydrophobic fumed silica together here to adjust the viscosity, and mixing at once to prepare PSAs by photopolymerization without interval.

That is, by simplifying the reaction process, as the reaction time until photopolymerization is shortened, it is possible to prevent the problem that the gel fraction is lowered due to the decay of free radicals, as well as the use of hydrophobic fumed silica. As a result, the viscosity can be controlled, so there is no need to use organic solvents that are harmful to the human body.

In the conventional acrylic PSA manufacturing method, the viscosity is adjusted through primary polymerization (prepolymerization), an initiator or a crosslinking agent is added again and mixed, and then, a second polymerization or polymer polymerization is performed by coating on a release film. After completing the first step, PSA was prepared by dissolving it in an organic solvent such as toluene and evaporating the solvent by coating.

That is, it was impossible to control the viscosity, so it was necessary to use an organic solvent. However, the use of such an organic solvent has a problem in that it must be used even though it is an organic solvent that is harmful to the human body.

In addition, there is a problem in that the gel fraction is lowered due to the decay of free radicals due to the short half-life during the time leading to the primary polymerization and the secondary polymerization. That is, since it is necessary to control the viscosity using an organic solvent, the reaction must be proceeded through primary polymerization and secondary polymerization, and as polymerization time increases, free radicals decline due to a short half-life, resulting in a decrease in polymerization rate.

In the present invention, unlike the conventional acrylic-based PSAs, the reaction leading to the primary and secondary polymerization is simplified, the reaction time is shortened, and the viscosity can be controlled without using an organic solvent harmful to the human body.

Accordingly, the pressure-sensitive adhesive composition used in the present invention is characterized in that it contains hydrophobic fumed silica for viscosity control.

The acrylate-based compound may include 2-ethylhexyl acrylate (2-EHA) and acrylic acid (AA), and 2-ethylhexyl acrylate (2-EHA) 80 to 95 based on the entire acrylate-based compound. It is preferable to include mol% and 5 to 20 mol% of acrylic acid (AA).

The laminate prepared using the pressure-sensitive adhesive composition of the present invention is 5 to 15% pre-strained after manufacturing, and the pre-strained laminate is originally at a strain change of 15% or less. It was confirmed that an immediate morphological recovery was possible. However, when the acrylic acid (AA) is added in excess of 20 mol%, even when 5 to 15% pre-strain is applied, it is impossible to immediately recover the shape to the original state under the same strain change. confirmed to be

The present inventor prepares a pressure-sensitive adhesive composition by adding 2EHA and 2AA in a ratio of 70:30 mol% in Examples of the present invention, and using this to prepare a film (laminate), 5 to 15% in the same manner as above -Even in the case of pre-straining, it was confirmed that the film (laminate) could not immediately recover its shape to its original state under the same strain change of 15% or less.

Therefore, in order to apply the method for imparting immediate deformation recovery of the pressure-sensitive adhesive of the present invention, it is preferable to include 80 to 95 mol% of 2-ethylhexyl acrylate (2-EHA) and 5 to 20 mol% of acrylic acid (AA), More specifically, 85 to 95 mol% of 2-ethylhexyl acrylate (2-EHA) and 5 to 15 mol% of acrylic acid (AA), more preferably 88 to 92 mol% of 2-ethylhexyl acrylate (2-EHA) mol% and 8 to 12 mol% of acrylic acid (AA).

The crosslinking agent is a material that chemically bonds the pressure-sensitive adhesive component to form a three-dimensional network structure, hexanediol diacrylate, ethylene glycol diacrylate, diethylene glycol diacrylate, triethylene glycol diacrylate, propylene glycol diacrylate Any one of acrylate, dipropylene glycol diacrylate and tripropylene diacrylate may be used, and hexanediol diacrylate may be preferably used.

The pressure-sensitive adhesive composition preferably contains 0.1 to 0.5 parts by weight of the crosslinking agent based on 100 parts by weight of the acrylate-based compound.

The photoinitiator refers to a chemical compound that decomposes into free radicals when initiating a UV-curing reaction with a UV photoinitiator, 2-benzyl-2-(dimethylamino)-1-(4-(4-morpholylyl)phenyl )-1-butanone (2-Benzyl-2-(dimethylamino)-1-(4-(4-morpholinyl)phenyl)-1-butanone), 2-hydroxy-2-methyl-1-phenyl-propane- 1-one (2-Hydroxy-2-methyl-1-phenyl-propane-1-one), diaminobenzo phenone (Diaminobenzo Phenone), 2-methyl-1-[4- (methylthio) phenyl]-2- Mortorino propan-1-one (2-Methyl-1- [4- (Methylthio) phenyl] -2-Mortholino Propan-1-one), 2,4-diethyl thioxanthone-9-one (2,4 -Diethyl thioxantone-9-one), 4- (diethylamino) benzoic acid 3-MB (4- (Dimethylamino) benzoic acid 3-MB), phenylbis (2,4,6-trimethyl-benzoyl) phosphine oxide (Phenylbis(2,4,6-trimethyl-benzoyl)-phosphinoxide), diphenyl(2,4,6-trimethylbenzoyl)-phosphine oxide (Diphenyl(2,4,6-trimethylbenzoyl)-phosphine oxide) and these Any one of the mixtures of can be used, preferably phenylbis (2,4,6-trimethyl-benzoyl) phosphine oxide (Phenylbis (2,4,6-trimethyl-benzoyl) -phosphinoxide) can be used.

The pressure-sensitive adhesive composition preferably contains 0.05 to 0.5 parts by weight of the photoinitiator based on 100 parts by weight of the acrylate-based compound. When the amount of the photoinitiator is less than 0.05 parts by weight of the composition, the composition tends to have difficulty curing by UV. When the amount of the photoinitiator is more than 0.5 parts by weight of the total weight of the composition, the composition tends to cure quickly, and furthermore, a higher amount of the photoinitiator may result in a lower molecular weight, which results in a lower cohesive strength of the cured product can do.

The filler is also referred to as a filler, increases the initial adhesion by increasing the apparent viscosity of the pressure-sensitive adhesive, and reinforces the amount or the pressure-sensitive adhesive layer, and the filler suitable for the present invention is, for example, calcium carbonate, calcium oxide, talc, coal tar, carbon black , textile fiber, glass particles in fiber or spherical form, hollow glass spheres, wollastonite, aramid pulp, boron fiber, carbon fiber, mineral silicate, mica, powdered quartz, hydrated aluminum oxide, bentonite, wollastonite, kaolin, hydrophobic fumed silica, Any one of silica airgel, metal powder such as aluminum powder or iron powder, and mixtures thereof may be used, and hydrophobic fumed silica may be preferably used.

The pressure-sensitive adhesive composition preferably contains 10 to 20 parts by weight of the filler based on 100 parts by weight of the acrylate-based compound.

The dispersing agent is for smoother dispersion of the composition, and BYK-type polyether-modified siloxane may be used, but a dispersant commonly used in the art may be added.

In the pressure-sensitive adhesive composition, in addition to those described above, if necessary, a color pigment, antioxidant, thickener, ultraviolet absorber, antifoaming agent, color separation inhibitor, hardness imparting agent, etc. are further added separately to improve thermal stability, improve abrasion resistance, Improvement of surface hardness and electrification can be pursued.

The adhesive force of the pressure-sensitive adhesive is 14 N/25mm or less, the light transmittance is 90% or more, the stress relaxation is 40% or more at 25% strain, the stress relaxation rate is 40% or more, and the resistance of the ITO substrate The rate of increase is less than 2%.

In addition, the ultimate tensile strength of the pressure-sensitive adhesive is 1.95 ± 0.1 MPa, Young's modulus is 3.5 ± 0.5 kPa, elongation at break is 425 ± 11.9%, and the glass transition temperature (Tg) is -54.3 °C.

According to another embodiment of the present invention, there is provided a laminate to which the method for imparting immediate strain recovery of an adhesive is applied, and the laminate is preferably for a flexible device.

A flexible device, unlike the conventional rigid and inflexible device, is flexible and can be deformed into a desired shape, such as being rolled, folded, or stretched, and can exhibit functions as a device even in a deformed state.

The flexible device may emit light, and may be an organic light emitting diode (OLED) device or a quantum dot device. In addition, the flexible device may include not only a self-light emitting device such as an OLED device or a quantum dot device, but also a non-self-emitting device such as a liquid crystal display (LCD). The flexible device may include a light emitting device and a driving circuit unit.

Furthermore, the flexible device may be a device other than the light emitting device. For example, the flexible element unit may include a flexible semiconductor element, a solar cell element, a battery element, a sensor element, and the like.

In the method for imparting immediate deformation recovery of the pressure-sensitive adhesive according to the present invention, when the laminate prepared from the pressure-sensitive adhesive composition is pre-strained by 5 to 15%, the pre-strained laminate has a strain of 15% or less Immediate shape recovery from strain change is possible, compatible with flexible/stretchable devices, light transmittance over 90% at 30% strain, corrosion resistance (ITO resistance increase rate less than 2%), high It has the characteristic of showing adhesiveness (65% higher than scotch tape).

1 is a measurement result of peel strength of a stretchable PSAs according to an embodiment of the present invention.
2 is a view showing stress-strain curves of a stretchable PSAs according to an embodiment of the present invention.
3 is a transmittance measurement result of a stretchable PSAs according to an embodiment of the present invention.
4 is a measurement result of stress relaxation of the stretchable PSAs according to an embodiment of the present invention.
5 is a stress-strain curve ( It is a diagram showing stress-strain curves).
6 is a diagram illustrating a resistance measurement method using a four-point probe.

Hereinafter, the present invention will be described in more detail through examples. These examples are only for illustrating the present invention in more detail, and it will be apparent to those of ordinary skill in the art that the scope of the present invention is not limited by these examples according to the gist of the present invention. .

<Example> Preparation of acrylate-based PSA

Acrylate-based PSA was synthesized by random copolymerization of acrylic monomers, namely 2-ethylhexyl acrylate (2EHA) and acrylic acid (AA), through a quick and easy UV curing process.

Various proportions of these monomers were added to form a solution mixture (Table 1).

Compositions 2EHA (mol%) AA (mol%) 1AA 90 10 3AA 70 30 5AA 50 50 7AA 30 70

15 wt% of hydrophobic fumed silica as a filler and 0.3 wt% of a dispersant (DISPERBYX-2158, BYK, Germany) were added to the mixture, respectively, and each chemical mixture was prepared using a vortex mixer.

In addition, 0.25 mol% of 1,6-hexanediol diacrylate (HDDA) and phenylbis (2,4,6-trimethyl-benzoyl) phosphine oxide (phenylbis (2) based on the total monomer concentration ,4,6-trimethyl-benzoyl) phosphine oxide, TCI) 0.1 mol% was used as a crosslinking agent and a photoinitiator.

The mixture was coated on a release film using a knife coating device. The laminate was then prepared and then cured under a UV lamp at a distance of 5 cm for 30 seconds. The thickness (B) of the synthesized PSA was 100 ± 10 μm.

<Experimental example>

1. Peel adhesion test

Peel adhesion was calculated using standard ASTM D3330, Test Method A; The average of at least 3 iterations was considered the final result.

Referring to Figure 1, 5AA and 7AA show almost zero adhesion, whereas 1AA and 3AA show high adhesion at ~13.8 N/25mm, which is a commonly used 'Scotch tape' (8.34 N/25mm) (PK65 48 × 40 transparent, 3M, USA) about 65% higher.

Subsequent experiments were conducted using 1AA.

2, tensile strength

The tensile strength of the pressure-sensitive adhesive prepared by using a UTM (Universal Testing Machine) was measured at room temperature at a rate of 500 mm/min.

As a result, ultimate tensile strength = 1.95 MPa, Young's modulus = 3.5 kPa, elongation at break = 425%, showing the general stress-strain curve trend of rubber.

3. Light transmittance

The transmittance of the synthesized PSA was measured by UV-Vis-NIR spectroscopy. PSA coating and bare glass were used as specimens and reference materials, respectively. The wavelength range scanned to determine transmittance was 350-700 nm.

Referring to FIG. 3 , the pressure-sensitive adhesive of the present invention exhibited a high transmittance of 90% or more in the visible ray region (400-700 nm) when strained by 0 to 30%.

4. stress relaxation

To test the stress relaxation, a strain of 1% to 300% was applied to the specimen and allowed to relax for 1 hour. The relaxation ratio was calculated as the ratio between the stress reduction after a relaxation time of 1 hour and the initial stress at each applied strain.

Referring to FIG. 4 , it shows a stress relaxation rate of 42.2% at 25% strain, which means that more than 40% of the stress applied to the adhesive by 25% strain can be relieved for 1 hour.

5. Elasticity

5 shows a stress-strain curve (100 cycles) of 1AA at 10% pre-strain. Referring to FIG. 5 , substantially the same hysteresis loss (0.219 ± 0.014 J/cm ³ except for the first cycle) was exhibited in each cycle, which reflects a behavior similar to that of the elastomer.

6. ITO corrosion resistance

The synthesized PSA was applied to an indium tin oxide (ITO)-coated glass substrate, and the specimen was exposed to hydrothermal conditions of 50° C. and 90% relative humidity for 2 weeks for 4 weeks. As shown in FIG. 6, the surface resistance was measured using a four-point probe, and the average surface resistance obtained at five different points of each specimen was recorded.

It was confirmed that the measured average resistance was 14.39 to 14.69 Ω/sq, which was rather increased by about 2% compared to the initial resistance value, and it was confirmed that the surface resistance did not actually change.

As described above in detail a specific part of the present invention, for those of ordinary skill in the art, this specific description is only a preferred embodiment, and it is clear that the scope of the present invention is not limited thereto. Accordingly, the substantial scope of the present invention will be defined by the appended claims and their equivalents.

Claims (27)

A method for imparting immediate strain recovery of an adhesive, comprising pre-straining a laminate comprising pressure sensitive adhesives (PSA).
According to claim 1,
The pressure-sensitive adhesive is acrylic, urethane, polyisobutylene, SBR (styrene-butadiene rubber), rubber, polyvinyl ether, epoxy, melamine, polyester, phenol, silicone, and copolymers thereof. A method for providing immediate deformation recovery properties of the pressure-sensitive adhesive, selected from the group.
According to claim 1,
The laminate is a base film laminated by the pressure-sensitive adhesive, the method for providing immediate deformation recovery properties of the pressure-sensitive adhesive.
4. The method of claim 3,
The base film is TAC (triacetyl cellulose); COP (cyclo olefin copolymer) such as norbornene derivatives; PMMA(poly(methyl methacrylate); PC(polycarbonate); PE(polyethylene); PP(polypropylene); PVA(polyvinyl alcohol); DAC(diacetyl cellulose); Pac(Polyacrylate); PES(poly ether sulfone); PEEK(polyetheretherketon) ); PPS (polyphenylsulfone), PEI (polyetherimide); PEN (polyethylenemaphthatlate); PET (polyethyleneterephtalate); PI (polyimide); PSF (polysulfone); A method of imparting immediate strain recovery of
According to claim 1,
The pre-strain (pre-strain) step is to pre-strain 5 to 15% of the laminate in its original state, the method for imparting immediate strain recovery of the pressure-sensitive adhesive.
According to claim 1,
By the pre-strain step, the pressure-sensitive adhesive can immediately recover its shape to its original state after deformation with respect to a strain of 15% or less.
According to claim 1,
Before the pre-strain step, applying a pressure-sensitive adhesive composition on a base film and laminating another base film, the method for providing immediate deformation recovery of the pressure-sensitive adhesive.
8. The method of claim 7,
Further comprising the step of curing the pressure-sensitive adhesive composition after the film lamination step, the immediate deformation recovery method of the pressure-sensitive adhesive.
8. The method of claim 7,
The pressure-sensitive adhesive composition may include an acrylate-based compound; crosslinking agent; photoinitiators; A method for imparting immediate deformation recovery of an adhesive, comprising a filler and a dispersant.
10. The method of claim 9,
wherein the acrylate-based compound includes 2-ethylhexyl acrylate (2-EHA) and acrylic acid (AA).
10. The method of claim 9,
The acrylate-based compound contains 80 to 95 mol% of 2-ethylhexyl acrylate (2-EHA) and 5 to 20 mol% of acrylic acid (AA) with respect to the entire acrylate-based compound. grant method.
10. The method of claim 9,
The filler for viscosity control is hydrophobic fumed silica, a method for imparting immediate deformation recovery of an adhesive.
10. The method of claim 9,
The crosslinking agent is a group consisting of hexanediol diacrylate, ethylene glycol diacrylate, diethylene glycol diacrylate, triethylene glycol diacrylate, propylene glycol diacrylate, dipropylene glycol diacrylate and tripropylene diacrylate. selected from, a method for imparting immediate deformation recovery properties of the pressure-sensitive adhesive.
10. The method of claim 9,
The photoinitiator is a UV photoinitiator, 2-benzyl-2-(dimethylamino)-1-(4-(4-morpholylyl)phenyl)-1-butanone (2-Benzyl-2-(dimethylamino)-1- (4-(4-morpholinyl)phenyl)-1-butanone), 2-hydroxy-2-methyl-1-phenyl-propane-1-one (2-Hydroxy-2-methyl-1-phenyl-propane-1 -one), diaminobenzo phenone (Diaminobenzo Phenone), 2-methyl-1- [4- (methylthio) phenyl] -2-mortorino propan-1-one (2-Methyl-1- [4- (Methylthio) )phenyl]-2-Mortholino Propan-1-one), 2,4-diethyl thioxantone-9-one (2,4-Diethyl thioxantone-9-one), 4- (diethylamino) benzoic acid 3 -MB(4-(Dimethylamino)benzoic acid 3-MB), phenylbis(2,4,6-trimethyl-benzoyl)phosphine oxide (Phenylbis(2,4,6-trimethyl-benzoyl)-phosphinoxide), diphenyl (2,4,6-trimethylbenzoyl) -phosphine oxide (Diphenyl (2,4,6-trimethylbenzoyl) -phosphine oxide) and a method for imparting immediate deformation recovery of the pressure-sensitive adhesive selected from the group consisting of mixtures thereof.
10. The method of claim 9,
The dispersant is a polyether-modified siloxane (Polyether-modified siloxane), the pressure-sensitive adhesive immediate deformation recovery method.
According to claim 1,
The pressure-sensitive adhesive has an adhesive force of 14 N/25mm or less, the method for imparting immediate deformation recovery properties of the pressure-sensitive adhesive.
According to claim 1,
The pressure-sensitive adhesive has a stress relaxation (stress relaxation) of 40% or more at 25% strain, an immediate strain recovery method of the pressure-sensitive adhesive.
According to claim 1,
The pressure-sensitive adhesive has a light transmittance of 90% or more, a method for providing immediate deformation recovery properties of the pressure-sensitive adhesive.
According to claim 1,
The pressure-sensitive adhesive has a stress relaxation rate of 40% or more, the method for imparting immediate deformation recovery properties of the pressure-sensitive adhesive.
According to claim 1,
The pressure-sensitive adhesive has a resistance increase rate of 2% or less of the ITO substrate, the method for imparting immediate deformation recovery properties of the pressure-sensitive adhesive.
According to claim 1,
The pressure-sensitive adhesive has a maximum tensile strength (Ultimate tensile strength) of 1.95 ± 0.1 MPa, the instantaneous deformation recovery method of the pressure-sensitive adhesive.
According to claim 1,
The pressure-sensitive adhesive has a Young's modulus (Young's modulus) of 3.5 ± 0.5 kPa, the method for imparting immediate deformation recovery of the pressure-sensitive adhesive.
According to claim 1,
The pressure-sensitive adhesive has an elongation at break of 425 ± 11.9%, a method for imparting immediate deformation recovery of the pressure-sensitive adhesive.
According to claim 1,
The pressure-sensitive adhesive has a glass transition temperature (T _g ) of -54.3° C., a method for imparting immediate deformation recovery properties of the pressure-sensitive adhesive.
The laminate to which the method of any one of claims 1 to 24 for imparting immediate deformation recovery properties of the pressure-sensitive adhesive is applied.
26. The method of claim 25,
The laminate is a flexible device for use.
A flexible device comprising the laminate of claim 26 .

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