Optical laminate and transparent display comprising same

Abstract

The utility model provides an optical laminated body and a transparent display comprising the same. The optical laminated body comprises a glass substrate; an adhesive layer formed on one surface of the glass substrate; a metal layer pattern formed on one surface of the adhesive layer; and a functional layer provided on a portion on one surface of the adhesive layer where the metal layer pattern is not formed, the adhesive layer including a silicon-based adhesive, and the functional layer including a solder resist layer.

Description

Technical Field

[0001] The utility model relates to an optical laminate and a transparent display comprising the same. Background Art

[0002] Recently, in the display market, the demand for large-area display devices has been increasing due to technological advances. Advanced electronic circuit and display business fields such as Micro-LED (micro light-emitting diode) and Mini-LED (mini light-emitting diode) that can control the contrast and brightness per unit area are also developing, and people are studying the photolithography method for producing electronic devices that meet large area size, high resolution and contrast quality at the same time.

[0003] Korean Patent Publication No. 10-2019-0003025 also discloses a circuit board and a method for manufacturing the same using a patterning process for a metal layer on top of a glass substrate.

[0004] However, conventionally, various methods such as electroplating or vapor deposition of metal thin films have been used as methods for realizing low-resistance metal wiring on glass substrates, but each of these methods has limitations due to the increase in the area of ​​displays.

[0005] In order to overcome such limitations, attempts have recently been made to develop a technology that patterns the metal thin film by using a photolithography method after bonding the metal thin film to a glass substrate.

[0006] However, the problem with this method of bonding a metal thin film to a glass substrate is that not only is the adhesion between the metal thin film and the glass substrate insufficient, but also the lower adhesive layer exposed after the metal layer is patterned is damaged by contact with a metal etching solution.

[0007] Furthermore, especially when used in electronic devices such as transparent displays that are exposed to the external environment for a long time, heat resistance and reliability in high temperature and high humidity environments are very important, but in the case of acrylic adhesives or epoxy adhesives used in existing metal films, there is a problem of insufficient heat resistance and reliability in high temperature and high humidity environments.

[0008] To solve this problem, when a metal film is bonded to a glass substrate using a silicone adhesive, the surface shape of the originally laminated metal will remain on the surface of the adhesive that is peeled off after the metal film is patterned, thereby creating roughness on the surface. Accordingly, when applied to a display, light is scattered on the surface of the adhesive layer where the metal film pattern is not formed, increasing the haze and causing a problem of reduced visibility.

[0009] Therefore, there is a need to develop an optical laminate and a transparent display having improved visibility in addition to adhesion to a glass substrate, chemical resistance to a metal layer etching solution, heat resistance, and reliability under a high-temperature and high-humidity environment.

[0010] Prior art literature

[0011] Patent Literature

[0012] Patent Document 1: Korean Patent Publication No. 10-2019-0003025 Utility Model Content

[0013] The utility model aims to provide an optical laminate having excellent adhesion to a glass substrate and excellent chemical resistance to etching liquid, heat resistance and reliability, that is, an optical laminate and a transparent display having improved visibility by reducing the haze of the surface.

[0014] In order to achieve the above-mentioned purpose, the utility model adopts the following technical scheme.

[0015] The utility model provides an optical laminate, comprising: a glass substrate; an adhesive layer formed on one surface of the glass substrate; a metal layer pattern formed on one surface of the adhesive layer; and a functional layer arranged on a portion of one surface of the adhesive layer where the metal layer pattern is not formed, wherein the adhesive layer comprises a silicon-based adhesive, and the functional layer comprises a solder resist layer.

[0016] According to the present invention, the functional layer can be configured to completely or partially cover the metal layer pattern.

[0017] According to the present invention, the thickness of the metal layer can be 3 μm to 120 μm.

[0018] According to the utility model, in a third aspect, the metal layer may include one or more selected from the group consisting of copper (Cu), aluminum (Al), nickel (Ni), chromium (Cr), silver (Ag), iron (Fe), gold (Au), cobalt (Co), titanium (Ti) and tungsten (W).

[0019] According to the utility model, the thickness of the adhesive layer can be 5 μm to 50 μm.

[0020] According to the present invention, no separate component may be included between the metal layer and the adhesive layer.

[0021] According to the utility model, the adhesion between the adhesive layer and the glass substrate can be 5B or more.

[0022] The utility model provides a transparent display, comprising the optical stacked body and a light emitting diode (LED).

[0023] According to the present invention, a transparent cover may be further included in the outermost portion corresponding to the glass substrate of the optical laminate.

[0024] According to the utility model, the transparent cover can be one or more selected from glass, wired glass, colored glass, magic mirror, and holographic glass.

[0025] According to the utility model, when the transparent cover is glass, it can also include at least one selected from wired glass, colored glass, magic mirror, and holographic glass.

[0026] The effects of the utility model are as follows.

[0027] According to the optical laminate and transparent display of the utility model, the effect of improving visibility can be obtained by reducing the surface roughness and reducing the haze. In particular, according to the optical laminate and transparent display of the utility model, since the solder resist layer is included as a functional layer, the generation of bubbles in the structure of the optical laminate is suppressed, thereby improving the reliability and long-term storage reliability. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is a figure which shows the optical laminated body of one or more examples of this invention.

[0029] Figure 2 2 is a diagram showing a transparent display according to one or more embodiments of the present invention.

[0030] Figure 3a and Figure 3b This is a diagram showing a method for producing an optical layered body according to an embodiment of the present invention.

[0031] Figure 3c The diagram shows a method for manufacturing a transparent display according to an example of the present invention, and is a diagram showing a step of mounting a light emitting diode 70 (LED).

[0032] Reference numerals

[0033] 10: metal layer, 20: adhesive layer, 30: protective film, 40: glass substrate, 50: photoresist pattern, 60: functional layer, 70: light emitting diode. DETAILED DESCRIPTION

[0034] The utility model relates to an optical laminate and a transparent display having an adhesive layer including a silicon-based adhesive. Since the adhesive surface peeled off after patterning of a metal thin film includes a functional layer, the surface roughness is reduced and the haze is reduced, thereby having the effect of improving visibility. In particular, according to the optical laminate and the transparent display of the utility model, since the solder resist layer is included as the functional layer, the generation of bubbles in the structure of the optical laminate is suppressed, thereby improving reliability and long-term storage reliability.

[0035] In more detail, the utility model relates to an optical laminate, which includes: a glass substrate; an adhesive layer formed on one side of the glass substrate; a metal layer pattern formed on one side of the adhesive layer; and a functional layer provided on a portion of one side of the adhesive layer where the metal layer pattern is not formed, the adhesive layer including a silicon-based adhesive, and the functional layer including a solder resist layer.

[0036] The following is a more detailed description of the embodiments of the present invention with reference to the accompanying drawings. However, the following drawings attached to this specification illustrate preferred embodiments of the present invention and are used together with the above-mentioned contents of the present invention to further understand the function of the technical idea of ​​the present invention, so the present invention should not be limited to the matters recorded in such drawings for interpretation.

[0037] The terms used in this specification are used to describe the embodiments and are not intended to limit the present invention. In this specification, unless otherwise stated in the context, the singular form also includes the plural form. For example, the "protective film" used in this specification may refer to at least one of the first protective film and the second protective film.

[0038] The terms "comprises" and / or "comprising" used in this specification are used to mean that they do not exclude the existence or addition of one or more other constituent elements, steps, actions and / or elements other than the mentioned constituent elements, steps, actions and / or elements. Throughout the specification, the same reference numerals refer to the same constituent elements.

[0039] "Below", "bottom", "lower part", "above", "top", "upper part" and the like as spatially relative terms can be used as shown in the figure to facilitate the description of the correlation between one element or constituent element and other elements or constituent elements. Spatially relative terms should be understood as terms that include different directions of elements when in use or operation in addition to the directions shown in the drawings. For example, when the elements shown in the figure are turned over, an element described as "below" or "lower part" of another element can also be placed "above" another element. Therefore, the exemplary term "below" can include both upper and lower directions. Elements can also be oriented in other directions, and accordingly, spatially relative terms can also be interpreted based on the orientation.

[0040] The term “substantially” as used in this specification may be interpreted as including not only being physically identical or identical but also being within a range of error in measurement or manufacturing process, for example, an error range of less than 0.1%.

[0041] <Optical laminate and transparent display>

[0042] Figure 1 1 is a diagram showing an optical laminate according to one or more embodiments of the present invention. Figure 2 2 is a diagram showing a transparent display according to one or more embodiments of the present invention.

[0043] Reference Figure 1 and Figure 2 , the optical laminate of one or more embodiments of the utility model may include a glass substrate 40, an adhesive layer 20, a metal layer 10 pattern, and a functional layer 60. In addition, the transparent display of the utility model may include the optical laminate, and a light emitting diode (LED). In addition, the transparent display may also include a transparent cover, and may also include a transparent cover (not shown) in the outermost contour corresponding to the glass substrate of the optical laminate. The transparent cover may be one or more selected from glass, wired glass, colored glass, magic mirror, and holographic glass. In addition, according to the utility model, when the transparent cover is glass, it may also include one or more selected from wired glass, colored glass, magic mirror, and holographic glass.

[0044] The glass substrate 40 is not particularly limited as long as it does not hinder the optical properties of the optical laminate, and can include, for example, oxide glass such as silicate glass, borate glass, phosphate glass, etc. In this case, there are advantages in that thermal shrinkage does not occur in subsequent processes, etc., and a predetermined hardness can be given to the optical laminate.

[0045] In one or more embodiments, the thickness of the glass substrate 40 may be 0.5 mm to 20 mm. When the thickness of the glass substrate 40 satisfies the range, the hardness is excellent and thinness can be achieved, and deformation or cracks of the metal layer 10 can be prevented. Specifically, when it is less than 0.5 mm, it may be difficult to protect the metal layer 10 or other laminated components from external impact, and when it exceeds 20 mm, it may be disadvantageous in thinness or lightness.

[0046] In one or more embodiments, the glass substrate 40 may have a single-layer or multi-layer structure. For example, the glass substrate 40 may have a single-layer structure formed by a single glass substrate, but is not necessarily limited thereto, and may also have a multi-layer structure having a plurality of glass substrates stacked.

[0047] In one embodiment, the optical laminate may include an adhesive layer 20 on one surface of the glass substrate 40 .

[0048] The adhesive layer 20 can be made of an adhesive layer composition including a silicon-based adhesive. The adhesive layer composition of the utility model includes a silicon-based additive and a solvent, and may also contain additives. Specifically, in the case of an adhesive layer formed using an existing acrylic adhesive or epoxy adhesive, there is a problem of insufficient adhesion to the glass substrate, or the adhesive layer is damaged by an etching solution used to etch a metal layer formed on the upper part of the adhesive layer. Furthermore, as in the case of a transparent display, when used for a product mainly used outdoors, there is a problem of decreased adhesion between the adhesive layer and the glass substrate or yellowing of the adhesive layer, which becomes a cause of product failure.

[0049] In order to solve this problem, the inventors of the present invention have proposed the present invention with an eye on the following aspects: when the adhesive layer 20 includes a silicon-based adhesive, it not only has excellent adhesion to the glass substrate, but also has excellent chemical resistance to etching liquid, and has excellent heat resistance and reliability in a high temperature and high humidity environment.

[0050] The silicon-based adhesive may be one or more of a silicon-based compound and a siloxane compound.

[0051] The use of the silicon compound is not particularly limited as long as it is a compound including a silicon (Si) atom. In addition, the siloxane compound can use a compound including a siloxane bond of a Si-O bond without restriction. More specifically, in one example of the present utility model, the silicon compound and the siloxane compound can be one or more of trimethylated silica, vinyl terminated polydimethylsiloxane, hexamethyl di siloxane, trisiloxane, and tetrakis (trimethylsilyloxy) silane.

[0052] In particular, preferably, the silicone adhesive of the present invention is contained in 40% to 60% of the total weight of the adhesive layer composition. In this way, the silicone adhesive of the present invention can be diluted and added at a concentration lower than that of conventional adhesives. Accordingly, when the adhesive layer of the present invention is bonded to a metal layer or a glass substrate, the adhesion to the metal layer or the glass substrate can be maximized, thereby having the advantage of achieving bonding without additional treatment such as UV curing of the adhesive layer.

[0053] The solvent is not particularly limited as long as it can dilute the silicon-based adhesive, and can be, for example, toluene, xylene, PGME, and / or PGMEA. From the perspective of the stability of the adhesive coating thickness under the metal layer, the solvent of the utility model is preferably contained in an amount of 40% to 55% relative to the total weight of the adhesive layer composition.

[0054] The additive may be one or more of an anchoring agent, a cross linker, and a catalyst.

[0055] The anchoring agent is added to increase the bonding strength with the metal layer when the adhesive layer is applied, and can prevent the adhesive layer from separating from the metal layer. Generally, there is no special restriction on the material used as the anchoring agent, but it is preferred that the material does not deform under heat at 200°C or below.

[0056] The crosslinking agent is a substance added for chemical bonding between the components of the adhesive layer composition, and is preferably a product that does not undergo thermal deformation at 200° C. or below.

[0057] The catalyst is a component added for curing the adhesive layer composition, and helps the adhesive layer composition to transform from a liquid phase to a solid phase. As specific examples, platinum catalysts, palladium catalysts, and / or osmium catalysts can be used.

[0058] From the aspect of stability of adhesive force, it is preferred that the additive of the present invention is contained in an amount of 0.1% to 10% relative to the total weight of the adhesive layer composition.

[0059] The adhesive layer 20 of the present invention can be formed by heating and curing the adhesive layer composition at a temperature of 100° C. to 180° C.

[0060] The thickness of the adhesive layer 20 may be 5 μm to 50 μm, preferably 5 μm to 30 μm, preferably 5 μm to 25 μm. When the thickness of the adhesive layer 20 is less than 5 μm, sufficient adhesion with other components cannot be maintained, and when the thickness exceeds 50 μm, it may be disadvantageous in increasing the thickness of the product.

[0061] In one embodiment, the adhesive layer 20 may not include a separate component, such as an intermediate layer or a protective layer, at the contact interface with the metal layer 10. Specifically, in the case of using a conventional acrylic adhesive or epoxy adhesive to form the adhesive layer, there are problems such as damage to the adhesive layer due to the etching solution used to form the etching on the adhesive layer that does not reach the metal layer, such as in the case of an adhesive layer formed by an epoxy adhesive, the non-transparency of the adhesive layer increases when in contact with the etching solution. Therefore, in the conventional optical laminate, in order to prevent the etching solution from causing damage to the adhesive layer, a component of an intermediate layer or a protective layer is separately included between the adhesive layer and the metal layer. However, when a separate component is included in this way, not only does the processability decrease and the manufacturing cost increase due to the increase in the manufacturing process, but there is also a problem of disadvantage in the production of the film. However, in the utility model, as described above, by using a silicone adhesive with excellent chemical resistance to the etching solution to form the adhesive layer, damage to the adhesive due to the etching solution does not occur, and therefore, a component of an intermediate layer or a protective layer that was previously provided to protect the adhesive is not separately included. By not including a separate member, it is advantageous not only in terms of improving processability but also in terms of reducing manufacturing costs, and further advantageous in terms of thinning the film.

[0062] In one embodiment, the adhesion between the adhesive layer 20 and the glass substrate 40 may be 5B or more. As described above, the adhesive layer 20 includes a silicon-based adhesive, and thus has a characteristic of excellent adhesion between the adhesive layer 20 and the glass substrate 40 .

[0063] In one embodiment, the adhesion strength of the adhesive layer 20 to the glass substrate 40 can be evaluated by measuring the standard ISO 2409: Standard Test Methods for Measuring Adhesion by Tape Test.

[0064] The metal layer 10 can be used as an electrode in an electronic device such as a display device including the optical laminate.

[0065] There is no particular limitation on the metal layer 10 as long as it is conductive. For example, it may include one or more selected from the group consisting of copper (Cu), aluminum (Al), nickel (Ni), chromium (Cr), silver (Ag), iron (Fe), gold (Au), cobalt (Co), titanium (Ti) and tungsten (W).

[0066] The metal layer 10 can be formed by a well-known metal thin film process, for example, by preparing and attaching a metal thin film, or by using at least one of electroless deposition, electrodeposition, sputtering, thermal evaporation, and electron beam evaporation, but is not limited thereto.

[0067] The thickness of the metal layer 10 may be 3 μm to 120 μm, preferably 3 μm to 110 μm, and more preferably 18 μm to 105 μm. When the thickness of the metal layer 10 is less than 3 μm, it may not be easy to form a uniform film or pattern, and when the thickness exceeds 120 μm, there may be a problem that it cannot be applied to electronic devices with thin film structures.

[0068] The functional layer 60 is formed on the portion of the adhesive layer 20 where the metal layer 10 pattern is not formed, that is, formed on the adhesive layer 20 exposed by etching the metal layer when the metal layer 10 pattern is formed. The functional layer 60 can be formed by filling Figure 1 More specifically, the adhesive layer 20 may be formed in a form that is connected to a portion of the adhesive layer 20 where the metal layer 10 is not formed and is stacked on the metal layer 10 .

[0069] More specifically, the functional layer may be formed to completely or partially cover the metal layer pattern. In one example of the present invention, when there are multiple metal layer patterns, the functional layer may be formed to completely cover or only partially cover the metal layer pattern. More preferably, Figure 1 As shown, it is preferably formed so that the functional layer 60 completely covers part of the metal layer pattern ( Figure 1 The left and right of the three metal layer patterns 10) and only partially cover part of the metal layer pattern ( Figure 1In this case, the metal layer pattern that only partially covers the functional pattern may be used to mount the light emitting diode 70 (LED). In addition, the metal layer pattern that completely covers the functional pattern may function as a wiring. In this way, when the functional layer is formed to only partially cover the metal layer pattern, the degree to which the functional layer is formed on the metal layer pattern is not particularly limited, as long as it is a degree suitable for mounting the light emitting diode 70 (LED).

[0070] On the other hand, as described above, the metal layer 10 is stacked on one surface of the adhesive layer 20 of the present invention, and the metal layer 10 may have a surface roughness (Rz) of 0.1 to 20 μm.

[0071] At this time, since the adhesive layer 20 includes a silicon-based adhesive layer, the surface morphology of the metal layer 10 is directly reflected in the adhesive layer 20. Therefore, when the metal layer 10 is peeled off after patterning, the surface of the adhesive layer 20 exposed by etching the metal layer generates concavities and convexities derived from the metal layer having a certain surface roughness, thereby causing light scattering when applied to a transparent display, resulting in a problem of increased haze.

[0072] Therefore, the functional layer 60 is provided at the portion of the adhesive layer 20 where the metal layer 10 pattern is not formed to prevent the surface unevenness of the adhesive layer 20 from occurring, thereby preventing scattering and reducing haze to improve visibility.

[0073] In this regard, the surface roughness (Rz) of the functional layer 60 may be 5.0 μm or less. When the surface roughness (Rz) exceeds 5.0 μm, scattering occurs, haze increases, and there is a problem of visual blurring.

[0074] The functional layer 60 may include a solder resist. Accordingly, not only can the transmittance and haze be reduced, but also the generation of bubbles in the structure of the optical stack can be suppressed, thereby improving reliability and long-term storage reliability. More specifically, the functional layer 60 may be formed by a solder resist. The solder resist may be formed by one of thermal curing, photocuring, and thermal photocuring, and may be one of a liquid type and a film type.

[0075] When the solder resist is a liquid type, it may be manufactured from a solder resist composition including a binder resin, a photopolymerizable compound, a photopolymerization initiator, a pigment, a dye, a solvent, and / or other additives.

[0076] When the solder resist is a liquid type, since printing and drying processes need to be repeated during production, in the present invention, a film type described later is more preferably used.

[0077] When the solder resist is a film type, it may include a protective film, a photosensitive resin layer, and a base film. The base film includes a polyester film such as polyethylene terephthalate and serves as a support. The protective film acts as a protective layer to prevent damage to the resist, but is not limited thereto. The photosensitive resin layer may use the same ingredients as the liquid solder resist composition.

[0078] Furthermore, when the solder resist is a film type, bubbles are less likely to be mixed between the substrate and the solder resist layer, and the film has excellent flatness, which is preferable in that a light emitting diode (LED) can be mounted efficiently and has high resolution.

[0079] The solder resist is used, for example, to form a solder resist layer of a wiring board, a circuit board, etc. In particular, a dry film solder resist is preferred.

[0080] The functional layer can be patterned by photolithography to form a portion covering only the metal layer pattern. Accordingly, the metal layer pattern can be coated in a form suitable for mounting a light emitting diode (LED) and then patterned. The specific method of photolithography is not particularly limited, but the content described in the following method for manufacturing an optical laminate can be applied without restriction.

[0081] The thickness of the functional layer 60 stacked on the metal layer 10 may be 1 μm to 3 mm.

[0082] As the light emitting diode (LED) 70 of the present invention, a known light emitting diode (LED) may be used without limitation.

[0083] <Method for producing an optical laminate>

[0084] Figure 3a and Figure 3b This is a diagram showing a method for producing an optical layered body according to an embodiment of the present invention.

[0085] Reference Figure 3a and Figure 3b , a method for manufacturing an optical laminate according to an embodiment of the utility model includes: a step of preparing a metal film, wherein the metal film includes a silicon-based adhesive layer 20 formed on one side of a metal layer 10, and includes a first protective film 30-1 provided on one side of the silicon-based adhesive layer 20, and a second protective film 30-2 provided on the other side of the metal layer 10; a step of peeling off the first protective film 30-1 of the metal film; a step of bonding the metal film in a manner of configuring the adhesive layer 20 on one side of a glass substrate 40; a step of peeling off the second protective film 30-2 of the metal film; a step of patterning the metal layer 10 to form a metal layer pattern; and a step of forming a functional layer 60 on a portion where the pattern of the metal layer 10 is not formed.

[0086] Specifically, in the step of peeling off the first protective film provided on the metal thin film, the first protective film 30 - 1 disposed on the lower surface of the adhesive layer 20 of the metal thin film may be peeled off.

[0087] The protective film 30 can be provided to protect the surface of the metal layer 10 and / or the adhesive layer 20 from external damage. For example, it can be provided in the form of a second protective film 30-2 formed on one surface of the metal layer 10 to protect the surface of the adhesive layer 20 and to protect the first protective film 30-1 formed on one surface of the adhesive layer 20 and the surface of the metal layer 10.

[0088] In one embodiment, the protective film can be used as Figure 2 Although a single-layer structure is shown, the present invention is not limited thereto and may be a multi-layer structure in which one or more protective films are continuously stacked.

[0089] In one embodiment, as for the protective film 30 , a second protective film 30 - 2 and a first protective film 30 - 1 may be laminated on one surface of the metal layer 10 and the adhesive layer 20 respectively by using a laminator.

[0090] The protective film 30 is not particularly limited as long as it is used to protect the surface of the metal layer 10 and / or the adhesive layer 20. For example, it can include a material selected from polyethylene terephthalate (PET), polyethylene isophthalate (PEI), polyethylene naphthalate (PEN), polybutylene terephthalate (PBT), diacetyl cellulose, triacetyl cellulose (TAC), polycarbonate (PC), polyethylene (PE), polypropylene (PP), polymethyl acrylate (PMA), polyimide (PI), polymethyl methacrylate (PMMA), polyethyl acrylate (PEA), polyethyl methacrylate (PEMA), and cyclic olefin polymer (cyclic olefin polymer). In terms of availability and processing convenience, polyethylene terephthalate (PET), triacetylcellulose (TAC), polycarbonate (PC), polyimide (PI), and cyclic olefin polymer (COP) can be preferably used.

[0091] The thickness of the protective film 30 is not particularly limited, and may be, for example, 10 μm to 200 μm.

[0092] On the other hand, although the above-mentioned metal film takes the metal film having the protective film 30 on one side of the metal layer 10 and the adhesive layer 20 respectively as an example, it is not limited to this. For example, it may also include only one of the protective film formed on one side of the metal layer and the protective film formed on one side of the adhesive layer.

[0093] In the step of peeling off the first protective film provided on the metal thin film, the first protective film 30 - 1 disposed on the lower surface of the adhesive layer 20 of the metal thin film may be peeled off.

[0094] The first protective film 30 - 1 may be peeled off appropriately within a range that does not hinder the purpose of the present invention, and a method used in a conventional process of peeling off a release film may be used.

[0095] In the step of bonding the metal thin film so as to arrange the adhesive layer on one surface of the glass substrate, the surface of the adhesive layer 20 exposed to the outside by peeling off the first protective film 30 - 1 may be bonded to one surface of the glass substrate 40 .

[0096] The bonding of the adhesive layer 20 and the glass substrate 40 may be appropriately performed within a range that does not hinder the purpose of the present invention. For example, the bonding may be performed using a laminator or the like.

[0097] In the step of peeling off the second protective film provided on the metal thin film, the second protective film 30 - 2 disposed on the upper surface of the metal layer 10 of the metal thin film may be peeled off.

[0098] The peeling of the second protective film 30 - 2 may be performed by substantially the same method as the peeling of the first protective film 30 - 1 .

[0099] On the other hand, although the method for producing the optical layered body in FIG. 3 is described by taking a method for producing the optical layered body using a metal thin film as an example, the method is not limited thereto.

[0100] For example, in another embodiment of the present invention, when the metal film does not include the second protective film 30 - 2 , the step of peeling off the second protective film provided on the metal film may be omitted.

[0101] The steps of forming a pattern of the metal layer 10 of an optical stack according to an embodiment of the present invention may include: forming a photoresist pattern 50 on one side of the metal layer 10; etching the exposed area of ​​the metal layer 10 through the photoresist pattern; and stripping the photoresist pattern.

[0102] Specifically, the step of forming a photoresist pattern 50 on one side of the metal layer 10 may include: a process of coating a composition for forming a photoresist pattern on the metal layer 10 by spin coating, slit coating, inkjet printing, etc., and a process of drying and heat treating the coated composition for forming a photoresist pattern to form a photoresist film, and a process of forming the photoresist pattern 50 by selectively exposing and developing the photoresist film to dissolve and remove the photoresist film corresponding to the exposed area or the non-exposed area.

[0103] The step of forming the photoresist pattern 50 may be performed by a known method, and the details are omitted here.

[0104] The step of etching the exposed region of the metal layer 10 through the photoresist pattern 50 is not particularly limited, and may be performed by a dry etching process or a wet etching process.

[0105] In one embodiment, the wet etching process can be performed using an etching solution including at least one selected from the group consisting of nitric acid, phosphoric acid, and acetic acid. As described above, the bonding layer 20 is characterized in that it includes a silicon-based adhesive and has excellent chemical resistance to an etching solution including at least one selected from the group consisting of nitric acid, phosphoric acid, and acetic acid. Therefore, when the etching process is performed by wet etching based on an etching solution including at least one selected from the group consisting of nitric acid, phosphoric acid, and acetic acid, not only is the etching performance of the metal layer 10 excellent, but even if the bonding layer 20 located at the bottom of the metal layer 10 is exposed to the etching solution, it is possible to achieve that no damage (physical and chemical damage and white turbidity phenomenon) to the bonding layer 20 occurs.

[0106] The dry etching process or the wet etching process may be performed by a known method, and the details are omitted here.

[0107] The step of stripping the photoresist pattern may be performed by immersing the substrate having the resist pattern 50 formed thereon in a resist stripping solution, or by spraying the stripping solution onto the substrate, etc. In this case, a physical treatment such as ultrasonic irradiation, contact with a rotating or swinging brush, etc. may also be used.

[0108] In one embodiment, as the resist stripping condition, the temperature can be about 15°C to 100°C, preferably 30°C to 70°C, and the immersion or spraying time is preferably about 1 minute to 20 minutes, but is not limited thereto and can be appropriately modified according to user needs.

[0109] In one embodiment, after the resist stripping solution treatment, a cleaning process may be further performed to remove the stripping solution remaining on the substrate. The cleaning process may be performed in the same manner as the stripping process described above, except that water or isopropyl alcohol is used instead of the stripping solution.

[0110] In an embodiment of the present invention, the step of forming the functional layer 60 may be a step of forming a liquid type solder resist layer or a film type solder resist layer, and preferably, may be a step of forming a film type solder resist layer.

[0111] The method of forming the functional layer 60 is not particularly limited, but any one of the liquid type and film type solder resist may be manufactured by a known method.

[0112] <Transparent display and method of manufacturing the same>

[0113] The utility model comprises a transparent display manufactured by utilizing the optical laminate of the utility model and a manufacturing method thereof.

[0114] Specifically, the utility model relates to a transparent display, which includes the above-mentioned optical laminate and a light emitting diode (LED). Figure 2 1 is a diagram showing an example of a transparent display according to the present invention. Figure 2 The transparent display of the utility model is in the form of a light emitting diode 70 (LED) formed on a portion of the patterned metal layer 10 of the optical laminate where the functional layer 60 is not formed. More specifically, the portion of the patterned metal layer 10 of the metal film substrate where the functional layer 60 is not formed may also include a solder layer (not shown), and the light emitting diode 70 (LED) may be mounted through the solder layer. The configuration interval or density of the light emitting diodes (LED) is not particularly limited, but may be configured in a grid form. In this case, the upper, lower, left, and right spacings may be 1 to 50 mm, and the spacings of the plurality of light emitting diodes (LEDs) may be the same or different from each other. When a light emitting diode (LED) is formed on the metal film substrate of the utility model, it has the advantage of being a transparent display capable of emitting and playing images on a substrate having transparency.

[0115] In addition, the manufacturing method of the transparent display of the utility model includes: a step of mounting a light emitting diode (LED) on the optical laminate. Figure 3c The transparent display manufacturing method according to one example of the present invention is a diagram showing a step of mounting a light emitting diode 70 (LED) on a portion of the patterned metal layer 10 of the optical laminate of the present invention where the functional layer 60 is not formed.

[0116] In the present invention, the method of forming the light emitting diode (LED) on the optical laminate of the present invention may be a method of surface mounting (SMT: Surface Mount Technology) of the device by soldering, etc., but is not limited thereto.

[0117] The utility model further includes an outer coating structure and method for covering the upper part of the light emitting diode (LED) or the entire transparent display. The outer coating can be made of conventionally known materials without limitation, and its thickness is not particularly limited, as long as it is a level commonly used by those skilled in the art.

[0118] The optical laminate of the present invention exhibits the above-mentioned characteristics, and therefore has the advantage that it can be suitable for use in display devices that require a large area and low resistance, and has excellent heat resistance and reliability in high temperature and high humidity environments, and is particularly suitable for use in devices such as transparent displays that may be exposed to the external environment for a long time.

[0119] Hereinafter, experimental examples including specific embodiments and comparative examples will be presented to help understand the present invention, but these are only examples of the present invention and do not limit the scope of the appended claims. It is obvious to those skilled in the art that various changes and modifications can be made to the embodiments within the scope of the present invention and the technical concept, and it is obvious that such changes and modifications also fall within the scope of the appended claims. In addition, unless otherwise stated, the "%" and "parts" indicating the content hereinafter are based on weight.

[0120] Examples and Comparative Examples: Preparation of Optical Laminated Body

[0121] Example 1

[0122] 4 kg of 99% toluene was added to 10 kg of a silicone adhesive (DOWSILTM 96-083 Silicone Adhesive Kit, DOW; solid content 70%) to prepare a composition having a silicone adhesive content of 50%, which was then stirred with a stirrer (5 horsepower) and further mixed with 0.5 g of an anchoring agent (SYL-OFFTM SL-9250, DOW), 0.8 g of a cross-linking agent (SYL-OFFTM 7678, DOW), and 1 g of a platinum catalyst as additives to prepare an adhesive layer composition.

[0123] Then, the adhesive layer composition was coated on one side of a 30 μm thick copper metal substrate (surface roughness (Rz) 9.0 μm) using a gravure coating method, and then cured at 150° C. for 2 minutes to produce a metal thin film having a 10 μm thick silicon-based adhesive layer formed on one side of the metal substrate.

[0124] After that, the adhesive layer of the metal thin film was disposed on one surface of a glass substrate having a thickness of 2 mm, and then the metal thin film was bonded by a sheet-to-sheet method to laminate a metal layer.

[0125] Then, as shown in FIG3 , the metal layer is patterned by photolithography to form a metal layer pattern. Figure 1As shown in FIG. 1 , a functional layer is formed by using a solder resist to produce the optical laminate of Example 1. Specifically, the solder resist is a monomer (ELVAROY TM , manufacturer: DOW) and adhesive (VORAMER TM , manufacturer: DOW), photoinitiator (IRGACURE 907, manufacturer: CIBA Specialty Chemicals (manufactured)) were mixed in a ratio of 5:3:2, and then PGMEA solvent was mixed with monomer, adhesive and photoinitiator mixture in a ratio of 5.5:4.5 to make a liquid solution. After uniformly coating the upper part of the film, it was dried in an oven at 85°C for 6 minutes to make a transparent dry film solder resist (Dry Film Solder Resist). At this time, the thickness of the functional layer was 50μm.

[0126] Example 2

[0127] In addition to the monomer ELVAROY TM , manufacturer: DOW) and adhesive (VORAMER TM , manufacturer: DOW), a photoinitiator (IRGACURE 907, manufacturer: CIBA Specialty Chemicals (manufactured)) was mixed in a ratio of 5:3:2 as a solder resist, and then a liquid solder resist prepared by mixing a PGMEA solvent with a monomer, an adhesive and a photoinitiator mixture in a ratio of 8:2 was used to manufacture the functional layer, and an optical laminate was manufactured by the same method as in the above-mentioned Example 1.

[0128] Example 3

[0129] An optical laminate was produced in the same manner as in Example 1 except that a copper metal substrate having a surface roughness (Rz) of 0.9 μm was used.

[0130] Comparative Example 1

[0131] An optical layered body was produced in the same manner as in Example 1 except that the functional layer was not formed.

[0132] Comparative Example 2

[0133] An optical layered body was produced in the same manner as in Example 3 except that the functional layer was not formed.

[0134] Comparative Example 3

[0135] An optical laminate was prepared in the same manner as in Example 1 except that the following transparent photosensitive resin composition was applied by a knife coater instead of the transparent dry film solder resist and then dried at 120° C. for 5 minutes to form a 5 μm thick negative transparent photosensitive resin composition layer.

[0136] For the transparent photosensitive resin composition, 16 grams of an acrylic resin having a weight average molecular weight of 10,100 g / mol, an acid value of 77 mgKOH / g, and an acrylic acid reactor ratio of 30 mol%, 7.5 grams of trihydroxypentitol hexaacrylate, 1 gram of BASF OXE-02 as a photoinitiator, and 0.5 grams of Glide-410 surfactant were dissolved in 75 grams of PGMEA (Propylene Glycol Mnomethyl Ether Acetate) and filtered with a 0.1 μm filter to prepare a transparent photosensitive resin composition.

[0137] 16 grams of acrylic resin with a weight average molecular weight of 10,100 g / mol, an acid value of 77 mgKOH / g, and an acrylic acid reactor ratio of 30 mol%, 7.5 grams of trihydroxypentyl alcohol hexaacrylate, 1 gram of BASF OXE-02 as a photoinitiator, and 0.5 grams of Glide-410 surfactant were dissolved in 75 grams of PGMEA (Propylene Glycol Mnomethyl Ether Acetate) and filtered with a 0.1 μm filter to prepare a transparent photosensitive resin composition. The back of the surface with the transparent photosensitive resin composition layer was irradiated with a light amount of 100 mJ / cm2 using a parallel light exposure machine (Karl Suss MA-8) and then developed to selectively remove the transparent photosensitive transparent resin composition layer coated on the copper foil pattern.

[0138] Experimental example

[0139] (1) Transmittance and haze evaluation

[0140] The transmittance and haze of the optical laminates of Examples and Comparative Examples were measured using a haze meter HM-150N (Murakami Co., Ltd.). The results are shown in Table 1 below.

[0141] (2) Evaluation of whether bubbles occur

[0142] The ratio of the bubble generation length to the total wiring length was measured for the optical laminates of Examples and Comparative Examples, and the results are shown in Table 1 below according to the following criteria.

[0143] ○: 0.5% or less

[0144] X: 1% or more

[0145] (3) Reliability evaluation

[0146] For the optical laminates of Examples and Comparative Examples including the functional layer, whether the film was physically damaged at the boundary of the functional layer near the wiring was evaluated, and the results are shown in Table 1 below according to the following criteria.

[0147] ○: No physical expansion of the film was observed at the boundary of the functional layer near the wiring

[0148] X: Physical opening of the film is observed at the boundary of the functional layer near the wiring

[0149] (4) Haze after long-term storage

[0150] The haze of the optical layered bodies of the examples and comparative examples was measured by the method (1) above after being left to stand at a high temperature of 90° C. for 500 hours. The results are shown in Table 1 below based on the following reference materials.

[0151] ○: Yellowish not observed

[0152] X: Yellowish observed

[0153]

Table 1

[0154]

[0155]

[0156] Referring to Table 1 above, it can be confirmed that the optical layered body of the example including the functional layer of the present invention has excellent transmittance and significantly low haze, and reduces the generation of bubbles, thereby improving reliability, compared with the comparative example not including the functional layer of the present invention.

[0157] That is, when comparing the optical laminates of Example 1 and Comparative Example 1 using metal substrates having the same surface roughness (Rz), and comparing the optical laminates of Example 3 and Comparative Example 2, it can be confirmed that the optical laminate of the embodiment including the functional layer of the utility model is excellent in transmittance and has significantly low haze compared to the comparative example not including the functional layer of the utility model. In particular, it was confirmed that in the case of Comparative Example 3 using a resin type as a functional layer, yellowing (Yellowish) was confirmed in terms of long-term reliability or when placed outdoors for a long time, thereby increasing haze.

[0158] In addition, in the case of Comparative Example 3, physical opening of the film was observed at the boundary of the functional layer near the wiring. This is because the boundary was exposed along the edge of the wiring during back exposure to form the functional layer, which means that the corresponding part is very likely to be damaged when exposed to the outside or heated, and the reliability is greatly reduced.

Claims

1. An optical laminate, characterized in that: include: Glass substrate; an adhesive layer formed on one surface of the glass substrate; a metal layer pattern formed on one side of the adhesive layer; as well as a functional layer provided on a portion of the adhesive layer on which the metal layer pattern is not formed, The adhesive layer includes a silicon-based adhesive, The functional layer includes a solder resist layer.

2. The optical layered body according to claim 1, wherein: The functional layer is arranged to completely or partially cover the metal layer pattern.

3. The optical laminate according to claim 1, wherein: The thickness of the metal layer is 3 μm to 120 μm.

4. The optical layered body according to claim 1, wherein: The metal layer includes at least one selected from the group consisting of copper, aluminum, nickel, chromium, silver, iron, gold, cobalt, titanium, and tungsten.

5. The optical layered body according to claim 1, wherein: The adhesive layer has a thickness of 5 μm to 50 μm.

6. The optical layered body according to claim 1, wherein: No separate components are included between the metal layer and the adhesive layer.

7. The optical layered body according to claim 1, wherein: The adhesion between the adhesive layer and the glass substrate is 5B or more.

8. A transparent display, characterized in that: include: The optical laminate according to any one of claims 1 to 7; as well as Light Emitting Diode.

9. The transparent display according to claim 8, characterized in that: The optical laminate further includes a transparent cover at the outermost portion corresponding to the glass substrate.

10. The transparent display according to claim 9, characterized in that: The transparent cover is one or more selected from glass, wired glass, colored glass, magic mirror, and holographic glass.

11. The transparent display according to claim 10, characterized in that: When the transparent cover is glass, it also includes at least one selected from wired glass, colored glass, magic mirror, and holographic glass.

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