KR20190025799A - Supporting substrate for flexible display apparatus, method of manufacturing the substrate, and flexible display apparatus having the substrate - Google Patents

Abstract

Disclosed is a substrate for a flexible display apparatus disposed under a flexible display panel and supporting the flexible display panel. The substrate comprises: a first base material layer; a second base material layer disposed to oppose the first base material layer; and a restoration layer disposed between the first and second base material layers to bond the first and second base material layers and having a restoration pattern layer on which a plurality of openings spaced apart from each other are formed. The support substrate may improve the flexibility and durability of a flexible display apparatus by having high restoring force.

Description

Technical Field [0001] The present invention relates to a supporting substrate for a flexible display device, a method of manufacturing the same, and a flexible display device including the supporting substrate. [0002]

The present invention relates to a substrate applied to a flexible display device, a method of manufacturing the same, and a flexible display device having the same.

Recently, many researches on flexible display devices have been conducted in terms of portability and space utilization. Such a flexible display device has evolved into a display device which can be simply bent or folded.

In such a flexible display device, since a flexible substrate is used instead of a conventional glass substrate, the durability of the display device may be deteriorated. In particular, in the case of a display device which can be folded or folded, the substrate supporting it must be capable of stably supporting the display panel against a number of repetitive strains.

It is an object of the present invention to provide a supporting substrate for a flexible display device with improved restoring force and flexibility.

Another object of the present invention is to provide a flexible display device having the support substrate.

A substrate for a flexible display device according to an exemplary embodiment of the present invention is disposed below a flexible display panel to support the flexible display panel, and includes a first substrate layer; A second base layer disposed to face the first base layer; And a restoration layer disposed between the first base layer and the second base layer to bond the first base layer and the second base layer and having a restoration pattern layer formed with a plurality of spaced-apart openings. In this case, the flexible display may be disposed on one of the first base layer and the second base layer.

In one embodiment, the first base layer and the second base layer may have the same strength, and the first base layer and the second base layer may be made of polycarbonate, polyethylene terephthalate, polyethylene naphthalate, and polymethyl Methacrylate, and the like.

In one embodiment, the strength of the second substrate layer may be less than the strength of the first substrate layer, wherein the first substrate layer is selected from the group consisting of polycarbonate, polyethylene terephthalate, polyethylene naphthalate and polymethylmethacrylate Rate, and the second substrate layer may be formed of an elastomeric material. For example, the second base layer may be formed of a silicone resin or a urethane resin.

In one embodiment, the openings may be elongated in a first direction, have the same shape, and may be spaced apart from each other by a predetermined distance in a second direction intersecting the first direction.

In one embodiment, the restoration pattern layer may have a lattice-like planar shape.

In one embodiment, the openings may be formed to penetrate the restoration pattern layer, or may be formed to have a depth smaller than the thickness of the restoration layer from one surface of the restoration pattern layer.

In one embodiment, the restoration pattern layer may be formed of a polymer compound of a first urethane acrylate oligomer compound, a bifunctional first acrylate monomer compound, and a monofunctional second acrylate monomer compound. In this case, the polymer compound may include chemical structures represented by the following formulas (1) to (3).

[Chemical Formula 1]

(2)

(3)

Wherein X and Y represent aliphatic hydrocarbons having 12 to 18 carbon atoms and aliphatic hydrocarbons having 6 to 13 carbon atoms, R1 and R2 each independently represent hydrogen or a methyl group, Ra, Rb , Rc and Rd independently represent hydrogen or a methyl group, and n is an integer of 6 or more and 12 or less.

In one embodiment, the first urethane acrylate oligomer compound may be a polymer of a bifunctional isocyanate compound and an acrylate compound having at least one hydroxy group in the molecule.

In one embodiment, the bifunctional isocyanate compound is 4,4'-dicyclohexyl diisocyanate, hexamethylene diisocyanate, 1,4-diisocyanatobutane, 1,6-diisocyanatohexane, 1 Diisocyanatohexane, 1,8-diisocyanatohexane, 1,8-diisocyanatohexane, 1,8-diisocyanatohexane, 1,8-diisocyanatohexane, Methylene) cyclohexane, trans-1,4-cyclohexene diisocyanate, 4,4'-methylenebis (cyclohexyl isocyanate), isophorone diisocyanate, toluene-2,4-diisocyanate, 1,3-diisocyanate, 1-chloromethyl-2,4-diisocyanate, 4,4'-methylenebis (2,6-dimethylphenyl) Isocyanate) and trimethane propanol adduct toluene diisocyanate. Acrylate compound having at least one hydroxyl group in the molecule may be at least one selected from the group consisting of hydroxyethyl acrylate, hydroxypropyl acrylate, hydroxyisopropylacrylate, hydroxybutyl acrylate, hydroxy Hydroxyethyl acrylate, butyl acrylate, butyl acrylate, butyl acrylate, butyl acrylate, pentyl acrylate, hydroxyhexyl acrylate, hydroxybutyl vinyl ether, hydroxyalkyl acrylate in which alkylene oxide is ring-opened and caprolactone ring-opening hydroxyacrylate.

In one embodiment, the first urethane acrylate oligomer compound may comprise a compound of Formula 4:

[Chemical Formula 4]

In Formula 4, X and Y each represent an aliphatic hydrocarbon having 12 to 18 carbon atoms and an aliphatic hydrocarbon having 6 to 13 carbon atoms, and R 1 and R 2 independently represent hydrogen or a methyl group. For example, the first urethane acrylate oligomer compound may include at least one selected from compounds represented by the following formulas (5) to (7).

[Chemical Formula 5]

[Chemical Formula 6]

(7)

In one embodiment, the bifunctional first acrylate monomer compound may be a polyethylene glycol diacrylate in which ethylene oxide is ring-opened having 1 to 50 repeating units, or a polypropylene glycol di Acrylate. ≪ / RTI >

In one embodiment, the monofunctional second acrylate monomer compound may comprise 2-hydroxyethyl acrylate or 2-hydroxypropyl acrylate.

In one embodiment, the restoration pattern layer may be formed by curing a composition comprising the first urethane acrylate oligomer compound, the first acrylate monomer compound, and the second acrylate monomer compound together with a photoinitiator and a solvent .

In one embodiment, the composition comprises 35 to 80 weight percent of the first urethane acrylate oligomer compound, 15 to 60 weight percent of the first acrylate monomer compound, and 3 to 20 weight percent of the first acrylate monomer compound, % Of said second acrylate monomeric compound.

In one embodiment, the photoinitiator may include a radical photopolymerization initiator or a cationic photopolymerization initiator.

In one embodiment, the composition may further comprise a third acrylate monomer compound having at least three functional groups. In this case, the third acrylate monomer compound may be contained in an amount of 10% by weight or less based on the weight of the total acrylate compound.

In one embodiment, the composition may further comprise a second urethane acrylate oligomer compound having not more than 2 functional groups. In this case, the composition may comprise the second urethane acrylate oligomer compound in an amount of up to 35% by weight based on the total weight of the acrylate compound.

In one embodiment, the restoration layer may further comprise a liquid or gel filler filling at least a portion of each of the openings. For example, the filler may comprise a liquid elastomer such as liquid silicone rubber (LSR) or the like.

A flexible display device according to an embodiment of the present invention includes a first substrate layer, a second substrate layer disposed to face the first substrate layer, and a second substrate layer disposed between the first substrate layer and the second substrate layer, A restoration layer including a restoration pattern layer having openings spaced apart from each other; And a flexible display panel disposed on one of the first base layer and the second base layer.

In one embodiment, the flexible display panel may include an OLED panel, an LCD panel, or an E-paper.

In one embodiment, the restoration pattern layer may be formed of a polymer compound of a first urethane acrylate oligomer compound, a bifunctional first acrylate monomer compound, and a monofunctional second acrylate monomer compound, wherein the polymer The compounds may include the chemical structures of the following formulas (1) to (3).

[Chemical Formula 1]

(2)

(3)

Wherein X and Y represent aliphatic hydrocarbons having 12 to 18 carbon atoms and aliphatic hydrocarbons having 6 to 13 carbon atoms, R1 and R2 each independently represent hydrogen or a methyl group, Ra, Rb , Rc and Rd independently represent hydrogen or a methyl group, and n is an integer of 6 or more and 12 or less.

According to the substrate for a flexible display device and the flexible display device including the substrate for the flexible display device of the present invention, it is possible to remarkably improve the folding performance by increasing the elongation of the supporting substrate by forming the opening in the restoring layer, The impact resistance of the support substrate and the flexible display device including the support substrate can be remarkably improved by absorbing an external impact through the opening.

Further, by forming the restoration pattern layer of the restoration layer from a material having a high restoration ratio, the restoring force and flexibility of the entire support substrate can be further improved, and as a result, it is possible to prevent repetitive deformation of the flexible display device such as rolling, folding, The display panel can be more stably supported even under a strong external impact.

1 is a cross-sectional view illustrating a substrate for a flexible display device according to an embodiment of the present invention.
2A and 2B are plan views for explaining embodiments of the restoration layer shown in FIG.
3 is a cross-sectional view illustrating a support substrate for a flexible display device according to another embodiment of the present invention.
4A and 4B are cross-sectional views illustrating a flexible display device according to an embodiment of the present invention.
5A and 5B are cross-sectional views illustrating a flexible display device according to another embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. The present invention is capable of various modifications and various forms, and specific embodiments are illustrated in the drawings and described in detail in the text. It is to be understood, however, that the invention is not intended to be limited to the particular forms disclosed, but on the contrary, is intended to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention. Like reference numerals are used for like elements in describing each drawing. In the accompanying drawings, the dimensions of the structures are enlarged to illustrate the present invention in order to clarify the present invention.

The terms first, second, etc. may be used to describe various components, but the components should not be limited by the terms. The terms are used only for the purpose of distinguishing one component from another. For example, without departing from the scope of the present invention, the first component may be referred to as a second component, and similarly, the second component may also be referred to as a first component.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The singular expressions include plural expressions unless the context clearly dictates otherwise. In the present application, the term "comprises" or "having ", etc. is intended to specify that there is a feature, step, operation, element, part or combination thereof described in the specification, , &Quot; an ", " an ", " an "

Unless defined otherwise, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Terms such as those defined in commonly used dictionaries are to be interpreted as having a meaning consistent with the contextual meaning of the related art and are to be interpreted as either ideal or overly formal in the sense of the present application Do not.

1 is a cross-sectional view illustrating a substrate for a flexible display device according to an embodiment of the present invention, and FIGS. 2A and 2B are plan views illustrating embodiments of the restoration layer shown in FIG.

1, 2A and 2B, a supporting substrate 100 for a flexible display device according to an embodiment of the present invention includes a first substrate layer 110, a second substrate layer 120, and a restoration layer 130, . ≪ / RTI > The support substrate 100 is disposed below and supports a flexible display panel such as an OLED panel (see '1200' in FIGS. 4A and 4B and '2200' in FIGS. 5A and 5B) And protects the display panel.

The first base layer 110 may be formed of a polymer material to improve the flexibility of the support substrate 100. For example, the first base layer 110 may be formed of polycarbonate, polyethylene terephthalate, polyethylene naphthalate, polymethylmethacrylate, or the like.

The second base layer 120 may be disposed to face the first base layer 110 and may be formed of the same or different polymer material as the first base layer 110.

In one embodiment, the second substrate layer 120 may have the same strength as the first substrate layer 110 to improve the flexibility of the support substrate 100. In this case, the second base layer 120 may be formed of the same material as the first base layer 110. Alternatively, in another embodiment, the second substrate layer 120 may be formed of a soft material having a lower strength than the first substrate layer 110 to further improve the foldability of the support substrate 100 have. In this case, the second base layer 120 may be formed of an elastomer material. For example, the second base layer 120 may be formed of a silicone resin, a urethane resin, or the like.

The restoration layer 130 may be disposed between the first base layer 110 and the second base layer 120 to bond the first base layer 110 and the second base layer 120 have.

In one embodiment, the restoration layer 130 may include restoration pattern layers 131a and 131b having a plurality of spaced-apart openings 132a and 132b. In one embodiment, the openings 132a and 132b may pass through the restoration pattern layers 131a and 131b.

2A, the restoration pattern layer 131a may have first openings 132a extending in a first direction Y and having the same shape as the first direction Y, The first direction X and the second direction X intersecting with each other. In this case, in order to prevent the adhesive force between the restoration pattern layer 131a and the first and second base layers 110 and 120 from being lowered, X are preferably smaller than the spacing W1 between the openings 132a. Although both ends of the openings 132a are shown as being sealed in FIG. 2A, both ends of the openings 132a may be opened.

In another embodiment, in order to more stably prevent the adhesive strength between the restoration pattern layer 131b and the first and second base layers 110 and 120 from being lowered, as shown in FIG. 2B, The pattern layer 131b may have a lattice shape. That is, the openings 132b having the same shape may be formed in a matrix shape so as to be spaced apart from each other in the first direction Y and the second direction X at regular intervals. In this case, the spacing H1 between the openings 132b in the first direction Y and the width H2 in the first direction Y of each of the openings 132b may be appropriately adjusted And a width W2 of each of the openings 132b in the second direction X may be smaller than a spacing W1 between the openings 132b. Although each of the openings 132b is shown as having a rectangular shape in FIG. 2B, the shape of each of the openings 132b may be variously changed, and may have a circular shape, for example.

The restoration coating layers 131a and 131b may be formed of a superior recovery material. In one embodiment, the restoration coating layers 131a and 131b may be formed of a polymer compound of a first urethane acrylate oligomer compound, a bifunctional first acrylate monomer compound, and a monofunctional second acrylate monomer compound. The first urethane acrylate oligomer compound and the first acrylate monomer compound may improve the restoring force of the restoration coating layers 131a and 131b and the second acrylate monomer compound may prevent the restoration coating layers 131a and 131b The composition comprising the first urethane acrylate oligomer compound, the first acrylate monomer compound and the second acrylate monomer compound can be reduced in viscosity to improve workability and moldability.

In one embodiment, the polymer compound of the first urethane acrylate oligomer compound, the bifunctional first acrylate monomer compound, and the monofunctional second acrylate monomer compound has the chemical structure of the following formula 1, the chemical structure of the following formula 2, And may include a chemical structure represented by the following formula (3). In this case, the chemical structure of Formula 1 may be derived from the first urethane acrylate oligomer compound, the chemical structure of Formula 2 may be derived from the first acrylate monomer compound, May be derived from the second acrylate monomer compound.

[Chemical Formula 1]

(2)

(3)

In Formula 1, X represents an aliphatic hydrocarbon having about 12 to 18 carbon atoms, Y represents an aliphatic hydrocarbon having about 6 to 13 carbon atoms, and R1 and R2 may independently represent hydrogen or a methyl group. On the other hand, the aliphatic hydrocarbon represented by X may or may not include a hetero atom.

In the general formulas (2) and (3), Ra, Rb, Rc and Rd may independently represent hydrogen or a methyl group, and n may be an integer of 6 or more and 12 or less.

In one embodiment, the first urethane acrylate oligomer compound may be formed by polymerizing a bifunctional isocyanate compound and an acrylate compound having at least one hydroxyl group in the molecule. In this case, the method of polymerizing the bifunctional isocyanate compound and the acrylate compound having at least one hydroxyl group in the molecule is not particularly limited. For example, they may be any polymerization reaction, block polymerization reaction, graft polymerization reaction And the like.

Examples of the bifunctional isocyanate compound include 4,4'-dicyclohexyl diisocyanate, hexamethylene diisocyanate, 1,4-diisocyanatobutane, 1,6-diisocyanatohexane, 1, Diisocyanatohexane, 8-diisocyanatooctane, 1,12-diisocyanatodecane, 1,5-diisocyanato-2-methylpentane, trimethyl-1,6-diisocyanatohexane, 1,3- ) Cyclohexane, trans-1,4-cyclohexene diisocyanate, 4,4'-methylenebis (cyclohexyl isocyanate), isophorone diisocyanate, toluene-2,4-diisocyanate, toluene- Diisocyanate, tetramethyl xylene-1,3-diisocyanate, 1-chloromethyl-2,4-diisocyanate, 4,4'-methylene bis (2,6-dimethylphenyl isocyanate ), Trimethylene propanol adduct, toluene diisocyanate, and the like There.

The acrylate compound having at least one hydroxy group in the molecule may be, for example, hydroxyethyl acrylate, hydroxypropyl acrylate, hydroxyisopropylacrylate, hydroxybutyl acrylate, hydroxypentyl acrylate, Hydroxybutyl acrylate, hydroxybutyl acrylate, hydroxyhexyl acrylate, hydroxybutyl vinyl ether, hydroxyalkyl acrylate in which alkylene oxide is ring-opened, caprolactone ring-opening hydroxyacrylate, and the like.

In one embodiment, the first urethane acrylate oligomer compound may comprise a compound of Formula 4:

[Chemical Formula 4]

In Formula 4, X and Y may represent aliphatic hydrocarbons having 12 to 18 carbon atoms and aliphatic hydrocarbons having 6 to 13 carbon atoms, respectively, and R 1 and R 2 may independently represent hydrogen or a methyl group.

For example, the first urethane acrylate oligomer compound may include at least one selected from compounds represented by the following formulas (5) to (7).

[Chemical Formula 5]

[Chemical Formula 6]

(7)

The compound of formula (5) can be synthesized, for example, by reacting isophorone diisocyanate with caprolactone acrylate. The compound of formula (6) can be produced, for example, by reacting isophorone diisocyanate with polyethylene glycol acrylate The compound of formula (7) can be synthesized, for example, by reacting isophorone diisocyanate with polypropylene glycol acrylate.

The bifunctional first acrylate monomer compound may be prepared from polyethylene glycol diacrylate in which ethylene oxide is ring-opened having a repeating unit of about 1 to 50, polypropylene glycol diacrylate in which propylene oxide having a repeating unit of about 1 to 50 is ring- And may include at least one selected. For example, the bifunctional first acrylate monomer compound may be a polyethylene glycol diacrylate having an ethylene oxide ring opening of about 6 to 14 repeating units, or a polypropylene glycol diacrylate having a propylene oxide ring opening of about 6 to 14 repeating units Rate, and the like.

The monofunctional second acrylate monomer compound may include at least one selected from 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate and the like.

Meanwhile, in the embodiment of the present invention, the restoration coating layers 131a and 131b include the first urethane acrylate oligomer compound, the bifunctional first acrylate monomer compound, and the monofunctional second acrylate monomer compound ≪ / RTI > composition. In one embodiment, the composition may further comprise a photoinitiator, a solvent, an additive, etc. together with the first urethane acrylate oligomer compound, the bifunctional first acrylate monomer compound and the monofunctional second acrylate monomer compound have. In addition, the composition may further comprise a polyfunctional third acrylate monomer compound.

The photoinitiator may include a radical photopolymerization initiator, a cationic photopolymerization initiator, and the like, which may be used alone or in combination of two or more.

As the radical photopolymerization initiator, known radical photopolymerization initiator compounds may be used without limitation and are not particularly limited. For example, the radical photopolymerization initiator may be 1-hydroxycyclohexyl phenyl ketone, 2,2'-dimethoxy-2-phenylacetophenone, xanthone, fluorene, fluorenone, benzaldehyde, anthraquinone, triphenylamine, Carbazole, 3-methylacetophenone, 4-chlorobenzophenone, 4,4'-dimethoxybenzophenone, 4,4'-diaminobenzophenone, mihira ketone, benzoylpropyl ether, benzoin ethyl ether, benzyldimethyl Ketal, 1- (4-isopropylphenyl) -2-hydroxy-2-methylpropan-1-one, 2-hydroxy- 2-isopropylthioxanthone, 2-chlorothioxanthone, 2-methyl-1- [4- (methylthio) phenyl] 1- (4-morpholinophenyl) butan-1-one, 1- [4- (2-hydroxyethoxy) -phenyl ] -2-hydroxy-2-methylpropan-1-one and the like .

As the cationic photopolymerization initiator, known cationic photopolymerization initiator compounds may be used without limitation and are not particularly limited. For example, the cationic photopolymerization initiator may include an onium salt, an organic metal salt, and the like. Specifically, the cationic photopolymerization initiator is selected from the group consisting of a diaryl iodonium salt, a triarylsulfonium salt, an aryldiazonium salt, an arylsulfonium hexafluoroantimonium salt, an arylsulfonium hexafluorophosphate salt, Diphenyl iodonium hexafluoroantimonium salt, diphenyl iodonium hexafluorophosphate salt, ditolyl iodonium hexafluorophosphate salt, 9- (4-hydroxyethoxyphenyl) cyan sulphonium hexa Fluorophosphate salts, iron-arene complexes, and the like. However, since the antimonium salt has environmental pollution problems, the cationic photopolymerization initiator is preferably a hexafluorophosphate salt-based compound.

The solvent may improve the applicability of the composition and may include at least one selected from an alcohol compound, a ketone compound, a hexane compound, a benzene compound, and the like. The alcohol-based compound may include at least one selected from methanol, ethanol, isopropanol, butanol, methylcellulose, and ethylsorbose. The ketone-based compound may include at least one selected from methyl ethyl ketone, methyl butyl ketone, methyl isobutyl ketone, diethyl ketone, dipropyl ketone, cyclohexanone, and the like. The hexane-based compound may include at least one selected from hexane, heptane, octane, and the like. The benzene-based compound may include at least one selected from benzene, toluene, xylene, and the like.

Meanwhile, the composition may further include additives commonly used in the art to which the present invention belongs, such as a surfactant, a yellowing inhibitor, and a leveling agent. The content of these additives may be in the range of about 0.1 to 10 parts by weight, but may be variously controlled within a range not deteriorating the physical properties of the present invention.

In one embodiment, the composition may comprise about 35 to 80 weight percent of the first urethane acrylate oligomer compound, based on the total weight of the acrylate compound. If the content of the first urethane acrylate oligomer compound is less than 35% by weight, the restoration rate of the restoration coating layers 131a and 131b may be lowered. If the content of the first urethane acrylate oligomer compound is less than 80% By weight, the viscosity of the composition may be excessively high, resulting in a problem that the moldability of the composition is deteriorated.

In one embodiment, the composition may comprise about 15 to 60 weight percent of the bifunctional first acrylate monomer compound, based on the total weight of the acrylate compound. If the content of the first acrylate monomer compound is less than 15% by weight, the restoration ratio of the restoration coating layers 131a and 131b may decrease. If the content of the first acrylate monomer compound exceeds 60% by weight , The curing shrinkage ratio of the composition increases, which may result in a problem that the workability of the work is lowered.

In one embodiment, the composition may comprise about 3 to 20 weight percent of the monofunctional second acrylate monomer compound, based on the total weight of the acrylate compound. If the content of the second acrylate monomer compound is less than 3% by weight, the viscosity of the composition may become excessively high and the moldability of the composition may be deteriorated. If the content of the second acrylate monomer compound is less than 20% , The restoration rate of the restoration coating layers 131a and 131b may be lowered.

In one embodiment, the composition may include the photoinitiator in an amount of about 1 to 3 wt%, and the solvent may be included in an amount of about 10 to 20 wt%.

On the other hand, when the composition further comprises the polyfunctional third acrylate monomer compound, the composition may comprise less than about 10% by weight of the third acrylate monomer compound.

In addition, the composition may further comprise a second urethane acrylate oligomer compound having not more than 2 functional groups independently of the first urethane acrylate oligomer compound, wherein the composition is based on the total weight of the acrylate compound And about 35% by weight or less of the second urethane acrylate oligomer compound.

In order to improve the mechanical durability of the support substrate 100 for a flexible display, the restoration layer 130 may fill at least a part of each of the openings 132a and 132b, (Not shown). For example, the filler may comprise a liquid or gel-like composition. Specifically, the filler may comprise a liquid elastomer, for example, a liquid silicone rubber (LSR).

3 is a cross-sectional view illustrating a support substrate for a flexible display device according to another embodiment of the present invention.

3, the support substrate 200 for a flexible display device according to an embodiment of the present invention includes a first substrate layer 210, a second substrate layer 220, and a restoration layer 230 ). The supporting substrate 200 according to the present embodiment is substantially the same as the supporting substrate 100 described with reference to FIGS. 1, 2A and 2B except for the structure of the openings 232 formed in the restoration layer 230 The detailed description will be omitted.

The restoration layer 230 may include a restoration pattern layer 231 having a plurality of spaced apart openings 232. The restoration pattern layer 231 and the first or second base layer 210, The opening portions 232 may be formed so as not to penetrate the restoration pad layer 231. [ For example, the openings 232 may be formed at a predetermined depth smaller than the thickness of the restoration layer 230 from one surface of the restoration pad layer 231. 3, the openings 232 are formed to have a predetermined depth from one surface of the restoration pattern layer 231 adhered to the second base layer 220, And may be formed at a predetermined depth from one surface of the restoration pattern layer 231 adhered to the base layer 210.

The planar shape of the openings 232 is substantially the same as the shapes of the openings 132a and 132b described with reference to FIGS. 2A and 2B, so that a detailed description thereof will be omitted.

The restoration layer 230 may further include a filler filling at least a portion of each of the openings 232. For example, the filler may comprise a liquid or gel-like composition. Specifically, the filler may comprise a liquid elastomer, for example, a liquid silicone rubber (LSR).

According to the support substrates 100 and 200 for a flexible display according to the embodiment of the present invention, the opening portions 132 and 232 are formed in the restoration layers 130 and 230, The folding performance can be remarkably improved by increasing the elongation of the supporting boards 100 and 200 and the impact resistance of the supporting boards 100 and 200 can be remarkably improved by absorbing the external impacts of the openings 132 and 232.

The restoration pattern layers 131 and 132 of the restoration layers 130 and 230 are formed of a material having a high recovery ratio so that the restoring force and flexibility of the entire support substrate 100 can be further improved. The display panel can be more stably supported by repeated deformations or strong external impacts of the flexible display device such as folding, folding, and the like.

Meanwhile, the flexible display panel may be arranged to be supported by the first substrate layers 110 and 210 or may be supported by the second substrate layers 120 and 220.

4A and 4B are cross-sectional views illustrating a flexible display device according to an embodiment of the present invention.

Referring to FIGS. 4A and 4B, the flexible display devices 1000a and 1000b according to the embodiment of the present invention include a support substrate 1100 and a display panel 1200. FIG.

The support substrate 1100 may include a first base layer 1110, a second base layer 1120, and a restoration layer 1130. Since the supporting substrate 1100 is substantially the same as the supporting substrate 100 for a flexible display device described with reference to FIG. 1, a detailed description thereof will be omitted.

The flexible display panel 1200 may be disposed on the support substrate 1100. In one embodiment, as shown in FIG. 4A, the flexible display panel 1200 may be disposed on the second base layer 1120 of the support substrate 1100. 4B, the flexible display panel 1200 may be disposed on the first base layer 1110 of the support substrate 1100. In this case, as shown in FIG.

The type of the flexible display panel 1200 is not particularly limited as long as it has a flexible characteristic. For example, the flexible display panel 1200 may include an OLED panel, an LCD panel, an E-paper, and the like.

For convenience of explanation, the flexible display panel 1200 is an OLED panel. The flexible display panel 1200 includes a panel substrate 1210 disposed on the first base layer 1110 or the second base layer 1120 of the supporting substrate 1100 and having a thin film transistor TFT, An organic light emitting layer 1220 disposed on the substrate 1210 and emitting light according to the operation of the thin film transistor and a protective layer 1230 disposed on the organic light emitting layer 1220 and protecting the organic light emitting layer 1220 can do. The flexible display panel 1200 may further include a sealing film and an optical film disposed between the organic light emitting layer 1220 and the passivation layer 1230.

5A and 5B are cross-sectional views illustrating a flexible display device according to another embodiment of the present invention.

5A and 5B, the flexible display devices 2000 a and 2000 b according to the embodiment of the present invention include a support substrate 2100 and a display panel 2200.

The support substrate 2100 is substantially the same as the support substrate 200 for a flexible display device described with reference to FIG. 3, and the flexible display panel 2200 is the same as the flexible display panel 1200 described with reference to FIGS. 4A and 4B ), So redundant detailed descriptions thereof are omitted.

The flexible display panel 2200 may be disposed on the second base layer 2120 of the support substrate 2100 as shown in FIG. 2100 may be disposed on the first base layer 2110.

According to the substrate for a flexible display device of the present invention and the flexible display device including the same, the support substrate includes a restoration layer formed of a material having high restoring force and having openings as described above, It is possible to stably support the display panel even with repeated deformations or strong external impacts of the flexible display device. As a result, the durability of the flexible display device can be remarkably improved.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the present invention as defined by the following claims. It can be understood that it is possible.

100, 200, 1100: Support substrate for flexible display device
110, 210: first base layer 120, 220: second base layer
130, 230: restoration layer 1000: display device
1200: display panel

Claims (27)

1. A substrate for a flexible display device disposed at a lower portion of a flexible display panel to support the flexible display panel,
A first base layer;
A second base layer disposed to face the first base layer; And
And a restoration layer disposed between the first base layer and the second base layer to bond the first base layer and the second base layer and having a restoration pattern layer formed with a plurality of spaced apart openings,
Wherein the flexible display is disposed on one of the first base layer and the second base layer. The method according to claim 1,
Wherein the first base layer and the second base layer have the same strength,
Wherein the first base layer and the second base layer are formed of one material selected from the group consisting of polycarbonate, polyethylene terephthalate, polyethylene naphthalate and polymethylmethacrylate. The method according to claim 1,
The strength of the second base layer is smaller than the strength of the first base layer,
Wherein the first base layer is formed of one material selected from the group consisting of polycarbonate, polyethylene terephthalate, polyethylene naphthalate and polymethylmethacrylate,
Wherein the second substrate layer is formed of an elastomeric material. The method according to claim 1,
Wherein the openings are elongated in a first direction and have the same shape and are spaced apart from each other by a predetermined distance in a second direction intersecting with the first direction. The method according to claim 1,
Wherein the restoration pattern layer has a lattice-like planar shape. The method according to claim 4 or 5,
Wherein the opening portions are formed to penetrate the restoration pattern layer. The method according to claim 4 or 5,
Wherein the openings are formed at a depth smaller than the thickness of the restoration layer from one surface of the restoration pattern layer. The method according to claim 1,
Wherein the restoration pattern layer is formed of a polymer compound of a first urethane acrylate oligomer compound, a bifunctional first acrylate monomer compound, and a monofunctional second acrylate monomer compound. 9. The method of claim 8,
A substrate for a flexible display device, characterized in that the polymer compound comprises the chemical structure of the following formulas (1) to (3):
[Chemical Formula 1]

(2)

(3)

Wherein X and Y represent aliphatic hydrocarbons having 12 to 18 carbon atoms and aliphatic hydrocarbons having 6 to 13 carbon atoms, R1 and R2 each independently represent hydrogen or a methyl group, Ra, Rb , Rc and Rd independently represent hydrogen or a methyl group, and n is an integer of 6 or more and 12 or less. 10. The method of claim 9,
Wherein the first urethane acrylate oligomer compound is a polymer of a bifunctional isocyanate compound and an acrylate compound having at least one hydroxyl group in the molecule. 11. The method of claim 10,
The bifunctional isocyanate compound is preferably selected from the group consisting of 4,4'-dicyclohexyl diisocyanate, hexamethylene diisocyanate, 1,4-diisocyanatobutane, 1,6-diisocyanatohexane, 1,8- Octane, 1,12-diisocyanatodecane, 1,5-diisocyanato-2-methylpentane, trimethyl-1,6-diisocyanatohexane, 1,3-bis (isocyanatomethyl) cyclohexane, 1,4-cyclohexene diisocyanate, 4,4'-methylenebis (cyclohexyl isocyanate), isophorone diisocyanate, toluene-2,4-diisocyanate, toluene-2,6-diisocyanate, xylene- Diisocyanate, tetramethyl xylene-1,3-diisocyanate, 1-chloromethyl-2,4-diisocyanate, 4,4'-methylene bis (2,6-dimethylphenyl isocyanate) And adduct toluene diisocyanate. And,
The acrylate compound having at least one hydroxy group in the molecule may be at least one selected from the group consisting of hydroxyethyl acrylate, hydroxypropyl acrylate, hydroxyisopropylacrylate, hydroxybutyl acrylate, hydroxypentyl acrylate, hydroxyhexyl acrylate, A hydroxybutyl vinyl ether, a hydroxybutyl vinyl ether, an alkylene oxide ring-opened hydroxyacrylate, and a caprolactone ring-opening hydroxyacrylate. 9. The method of claim 8,
Wherein the first urethane acrylate oligomer compound comprises a compound of Formula 4: < EMI ID =
[Chemical Formula 4]

In Formula 4, X and Y each represent an aliphatic hydrocarbon having 12 to 18 carbon atoms and an aliphatic hydrocarbon having 6 to 13 carbon atoms, and R1 and R2 independently represent hydrogen or a methyl group. 13. The method of claim 12,
Wherein the first urethane acrylate oligomer compound comprises at least one selected from the group consisting of compounds represented by the following formulas (5) to (7):
[Chemical Formula 5]

[Chemical Formula 6]

(7)

9. The method of claim 8,
The bifunctional first acrylate monomer compound includes polyethylene glycol diacrylate in which ethylene oxide having a repeating unit of 1 to 50 is opened or polypropylene glycol diacrylate in which propylene oxide having a repeating unit of 1 to 50 is opened Wherein the substrate is a substrate for a flexible display device. 9. The method of claim 8,
Wherein the monofunctional second acrylate monomer compound comprises 2-hydroxyethyl acrylate or 2-hydroxypropyl acrylate. 9. The method of claim 8,
Wherein the restoration pattern layer is formed by curing a composition comprising the first urethane acrylate oligomer compound, the first acrylate monomer compound and the second acrylate monomer compound together with a photoinitiator and a solvent. Board. 17. The method of claim 16,
Wherein the composition comprises from 35 to 80% by weight, based on the total weight of the acrylate compound, of the first urethane acrylate oligomer compound, from 15 to 60% by weight of the first acrylate monomer compound and from 3 to 20% Lt; RTI ID = 0.0 > 1, < / RTI > a late monomer compound. 17. The method of claim 16,
Wherein the photoinitiator comprises a radical photopolymerization initiator or a cationic photopolymerization initiator. 17. The method of claim 16,
Characterized in that the composition further comprises a third acrylate monomer compound having at least three functional groups. 20. The method of claim 19,
Wherein the third acrylate monomer compound is contained in an amount of 10 wt% or less based on the weight of the total acrylate compound. 17. The method of claim 16,
Characterized in that the composition further comprises a second urethane acrylate oligomer compound having a functionality of 2 or less. 22. The method of claim 21,
Wherein the composition comprises the second urethane acrylate oligomer compound in an amount of up to 35 weight percent based on the total weight of the acrylate compound. The method according to claim 1,
Wherein the restoration layer further comprises a liquid or gel filler filling at least a portion of each of the openings. 24. The method of claim 23,
≪ / RTI > wherein the filler comprises a liquid elastomer. A second base layer disposed to face the first base layer, and a restoration pattern layer disposed between the first base layer and the second base layer and adhered to each other to form a plurality of spaced- A support substrate including a restoration layer; And
And a flexible display panel disposed on one of the first base layer and the second base layer. 26. The method of claim 25,
Wherein the flexible display panel includes an OLED panel, an LCD panel, or E-paper. 26. The method of claim 25,
Wherein the restoration pattern layer is formed of a polymer compound of a first urethane acrylate oligomer compound, a bifunctional first acrylate monomer compound, and a monofunctional second acrylate monomer compound,
A substrate for a flexible display device, characterized in that the polymer compound comprises the chemical structure of the following formulas (1) to (3):
[Chemical Formula 1]

(2)

(3)

Wherein X and Y represent aliphatic hydrocarbons having 12 to 18 carbon atoms and aliphatic hydrocarbons having 6 to 13 carbon atoms, R1 and R2 each independently represent hydrogen or a methyl group, Ra, Rb , Rc and Rd independently represent hydrogen or a methyl group, and n is an integer of 6 or more and 12 or less.

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