KR102233236B1 - Plastic laminate, preparation method thereof and plastic molded product obtained therefrom - Google Patents

Abstract

A plastic laminate according to the present invention is designed to have a symmetrical laminate structure of a plastic film having a hard coating layer, so that curling can be remarkably reduced in a high-temperature environment. Since the thickness, components, and process conditions of each layer of the plastic laminate are controlled, not only dimensional stability, but also other properties, such as antifouling properties, printability, and the like, can be increased. In particular, the plastic laminate has a thickness and mechanical and optical properties, which can be applied to mobile devices that are recently manufactured in various standards, thereby being used in various ways. Accordingly, a plastic molded product molded from the plastic laminate has an advantage of reducing costs due to multifunctional complexation while having high durability, thereby being applied as a front or back cover or a front protective film of the mobile device by replacing the conventional glass material. The plastic laminate comprises a core substrate layer, a first sheet, and a second sheet.

Description

Plastic laminate, manufacturing method thereof, and plastic molded article {PLASTIC LAMINATE, PREPARATION METHOD THEREOF AND PLASTIC MOLDED PRODUCT OBTAINED THEREFROM}

The present invention relates to a plastic laminate, a method for producing the same, and a plastic molded body. Specifically, the present invention relates to a cover made of a plastic material that can replace a glass material applied as a front or rear cover or a front protective film of a mobile device.

Glass materials having advantages in appearance, dimensional stability, and optical properties are generally used for the front or rear cover or front protective film of a mobile device. However, as described above, the front or rear cover or front protective film made of a glass material used in a mobile device is likely to be broken and scattered due to an external impact. In addition, in accordance with the recent trend toward large-area mobile devices, when using a cover made of a glass material, it is difficult to reduce weight and increase cost.

Accordingly, attempts have been made to develop a cover using a plastic material in place of the glass material. In particular, plastic materials are lightweight, have excellent impact resistance, are not scattered even if they are broken, and have low cost.

Meanwhile, the front or rear cover or the front protective film is required to protect the mobile device from the external environment, and for this purpose, a hard coating layer is formed on the external exposed surface of the plastic substrate layer to improve surface hardness and durability. In addition, since various designs are applied to the cover of the mobile device, it is required to impart advantageous properties of mold molding or printing to the hard coating layer disposed inside the device.

In particular, since mobile devices are manufactured in various standards and shapes and it is difficult to apply glass materials, plastic materials having thickness, mechanical and optical properties applicable to these mobile devices are continuously being studied.

Korean Patent Application Publication No. 2017-5755

Despite the many advantages of the hard coating film made of plastic material for application to mobile devices, curling occurs due to the difference in heat shrinkage between layers in a high-temperature environment and has low dimensional stability.

Accordingly, as a result of research by the present inventors, by designing a plastic film with a hard coating layer in a symmetrical lamination structure, it was possible to significantly reduce the occurrence of curls in a high temperature environment. In addition, by controlling the thickness, components, and process conditions of each layer of the laminate, properties such as dimensional stability as well as other antifouling properties and printability could be further improved.

Accordingly, an object of the present invention is to provide a plastic laminate having improved low dimensional stability and other properties of a conventional hard coating film, and a method for manufacturing the same. In addition, the object of the present invention is to reduce costs due to multifunctional composites while having high durability, which can replace the glass material applied as a front or rear cover or a front protective film of a conventional mobile device by using the plastic laminate. possible It is to provide a plastic molded body.

In particular, an object of the present invention is to provide a plastic laminate having a thickness, mechanical and optical properties that can be applied to mobile devices manufactured to various standards in recent years, and a plastic molded article obtained therefrom.

According to the above object, the present invention is a core substrate layer; A first sheet including a first substrate layer and a first hard coating layer sequentially disposed on one surface of the core substrate layer; And a second sheet including a second base layer and a second hard coating layer sequentially disposed on the other surface of the core base layer, wherein the first sheet and the second sheet are 1: 0.9 to 1: 1.1 It provides a plastic laminate having a thickness ratio.

According to the above other object, the present invention provides a step of forming a first hard coating layer on a first base layer to obtain a first sheet; Forming a second hard coating layer on the second base layer to obtain a second sheet; Laminating the first sheet on one surface of the core base layer so that the first base layer faces; And laminating the second sheet on the other surface of the core base layer so that the second base layer faces, wherein the first sheet and the second sheet have a thickness ratio of 1: 0.9 to 1: 1.1. , It provides a method of manufacturing a plastic laminate.

According to one embodiment, the first sheet and the second sheet have a thickness ratio of 1: 0.9 to 1: 1.1, the core base layer has a thickness of 25 μm to 1000 μm, the first base layer and the The second base layer has a thickness of 10 μm to 500 μm, the first hard coat layer and the second hard coat layer have a thickness of 3 μm to 6 μm, and a urethane acrylate oligomer resin having 6 to 10 functional groups, or A resin derived therefrom is included, and after the plastic laminate is left at 140° C. for 2 hours, it has a curl change of 0.3 mm or less in the corners.

According to the another object, the present invention provides a plastic molded body molded from the plastic laminate.

The plastic laminate according to the present invention includes a plastic film on which a hard coating layer is formed in a symmetrical structure, so that the occurrence of curls can be minimized even in a high temperature environment. In addition, the plastic laminate may further improve dimensional stability as well as other properties such as antifouling properties and printability by adjusting the thickness, components, and process conditions of each layer. In particular, the plastic laminate can be used in various ways because of its thickness, mechanical and optical properties applicable to mobile devices manufactured in various standards in recent years.

Accordingly, the plastic molded body molded from the plastic laminate has high durability and can reduce costs due to multifunctional composites. Since it can be used in various ways with advantages, it can be usefully applied as a front or rear cover or a front protective film of a mobile device by replacing a conventional glass material.

1 is a cross-sectional view of a plastic laminate according to an embodiment of the present invention.
2 is a cross-sectional view of a plastic laminate according to another embodiment of the present invention.

Hereinafter, with reference to the accompanying drawings for the present invention will be described in more detail. In the accompanying drawings, sizes or intervals may be exaggerated and displayed for better understanding, and the illustration may be omitted for contents that are obvious to those of ordinary skill in the art.

In the following description, when each component is described as being disposed above or below the other component, it should be understood that all cases with or without another component between these components are included.

In the present specification, that a certain component "includes" another component means that it may further include another component unless otherwise specified.

1 is a cross-sectional view of a plastic laminate according to an embodiment of the present invention.

Plastic laminate according to the present invention, with reference to Figure 1, the core base material layer 100; A first sheet 10 including a first base layer 210 and a first hard coating layer 310 sequentially disposed on one surface of the core base layer 100; And a second sheet 20 including a second base layer 220 and a second hard coating layer 320 sequentially disposed on the other surface of the core base layer 100, and the first sheet 10 ) And the second sheet 20 has a thickness ratio of 1: 0.9 to 1: 1.1.

In addition, the plastic laminate may include a first adhesive layer 410 disposed between the core base layer 100 and the first sheet 10; And a second adhesive layer 420 disposed between the core base layer 100 and the second sheet 20.

Hereinafter, it will be described in more detail for each constituent layer.

Core base layer

The core base layer is located at the center of the plastic laminate, and serves as a support for the entire structure and imparts moldability.

The core substrate layer may include a polymer resin, for example, a transparent polymer resin.

Specifically, the core substrate layer is polyethylene terephthalate (PET), polyimide (PI), cyclic olefin polymer (COP), polyethylene naphthalate (PEN), polyethersulfone (PES), polycarbonate (PC), polyether A polymer resin selected from the group consisting of ether ketone (PEEK), polyphenylene sulfide (PPS), polyamide (PA), polycyclohexylenedimethylene terephthalate (PCT) and polypropylene (PP), or alloys thereof Resin (for example, PC/PCT alloy resin or PET/PCT alloy resin).

As a specific example, the core substrate layer may include polycarbonate, polyethylene terephthalate (PET), polycyclohexylenedimethylene terephthalate (PCT), or an alloy resin thereof. More specifically, the core substrate layer containing polycarbonate may be more advantageous in imparting moldability and suppressing curl.

The thickness of the core substrate layer is in the range of 25 µm to 1000 µm, and it is advantageous to suppress curl while having support for the entire structure and moldability.

For example, the thickness of the core substrate layer may be 25 μm or more, 50 μm or more, 100 μm or more, 150 μm or more, 200 μm or more, 250 μm or more, or 300 μm or more. In addition, the thickness of the core substrate layer may be 1000 µm or less, 700 µm or less, 600 µm or less, 500 µm or less, 450 µm or less, 300 µm or less, 250 µm or less, or 200 µm or less.

As a specific example, the thickness of the core substrate layer may be 25 µm to 500 µm, 50 µm to 500 µm, 100 µm to 500 µm, or 150 µm to 500 µm. In another embodiment, the thickness of the core substrate layer may be 100 µm to 1000 µm, 100 µm to 600 µm, 150 µm to 500 µm, 200 µm to 450 µm, 200 µm to 300 µm, or 300 µm to 500 µm. have.

1st sheet and 2nd sheet

The first sheet includes a first base layer and a first hard coating layer sequentially disposed on one surface of the core base layer. In addition, the second sheet includes a second base layer and a second hard coating layer sequentially disposed on the other surface of the core base layer.

The first base layer and the second base layer each serve to support the first hard coat layer and the second hard coat layer.

The first sheet and the second sheet have a thickness ratio of 1: 0.9 to 1: 1.1. When within the above range, the first sheet and the second sheet have a symmetrical structure with respect to the core substrate layer, so that the occurrence of curls can be drastically suppressed. More specifically, the first sheet and the second sheet may have a thickness ratio of 1: 0.99 to 1: 1.01.

The first sheet and the second sheet may have a symmetrical structure in terms of detailed layer thickness.

Specifically, the first hard coating layer and the second hard coating layer have a thickness ratio of 1: 0.9 to 1: 1.1, and the first substrate layer and the second substrate layer have a thickness ratio of 1: 0.9 to 1: 1.1. I can.

More specifically, the first hard coating layer and the second hard coating layer have a thickness ratio of 1: 0.99 to 1: 1.01, and the first substrate layer and the second substrate layer have a thickness ratio of 1: 0.99 to 1: 1.01 I can have it.

The thickness of the first base layer and the second base layer is in the range of 10 μm to 500 μm, respectively, which is more advantageous in suppressing curl while supporting the hard coat layer well.

For example, the thickness of the first base layer and the second base layer may be 10 μm or more, 25 μm or more, 50 μm or more, 75 μm or more, 100 μm or more, 150 μm or more, or 200 μm or more, respectively. In addition, the thicknesses of the first base layer and the second base layer may be 500 μm or less, 400 μm or less, 300 μm or less, 200 μm or less, or 150 μm or less, respectively.

As a specific example, the thickness of the first base layer and the second base layer may be 10 µm to 300 µm, 10 µm to 200 µm, 75 µm to 200 µm, 25 µm to 500 µm, or 50 µm to 500 µm have. As another specific example , the thickness of the first base layer and the second base layer is 10 µm to 500 µm, 50 µm to 300 µm, 100 µm to 200 µm, 100 µm to 150 µm, or 150 µm to 200 µm, respectively. Can be

The thickness of the first hard coating layer and the second hard coating layer may be 1 μm or more, 2 μm or more, 3 μm or more, 4 μm or more, or 5 μm or more, respectively. In addition, the thickness of the first hard coating layer and the second hard coating layer may be 50 μm or less, 30 μm or less, 20 μm or less, 10 μm or less, 8 μm or less, 7 μm or less, or 6 μm or less, respectively. For example, the thickness of the first hard coating layer and the second hard coating layer is 1 μm to 50 μm, 1 μm to 30 μm, 1 μm to 20 μm, 1 μm to 10 μm, 3 μm to 10 μm or 5 μm, respectively. It may be to 10㎛. Specifically, the thickness of the first hard coating layer and the second hard coating layer is 3㎛ to 6㎛ is advantageous for curl suppression.

The first base layer and the second base layer may include a polymer resin, and specifically, a transparent polymer resin.

For example, the first base layer and the second base layer are polyethylene terephthalate (PET), polyimide (PI), cyclic olefin polymer (COP), polyethylene naphthalate (PEN), polyethersulfone (PES), Polycarbonate (PC), polyetheretherketone (PEEK), polyphenylene sulfide (PPS), polyamide (PA), polycyclohexylenedimethylene terephthalate (PCT) and polypropylene (PP) Polymer resins, or alloy resins thereof (eg, PC/PCT alloy resin or PET/PCT alloy resin) may be included.

As a specific example, the first base layer and the second base layer may each include polycarbonate, polyethylene terephthalate (PET), polycyclohexylenedimethylene terephthalate (PCT), or alloy resins thereof. . More specifically, the first base layer and the second base layer containing polyethylene terephthalate may be more advantageous in imparting stability and suppressing curl after molding.

The first hard coating layer and the second hard coating layer are disposed outside the plastic laminate to improve surface hardness, antifouling property, and printability.

The first hard coating layer and the second hard coating layer may include a thermoplastic resin, a thermosetting resin, a UV curable resin, and the like, and preferably, a UV curable resin to increase the surface hardness to exhibit high hard coating properties. have.

Specific examples of the thermoplastic resin and thermosetting resin include acrylic resin, urethane resin, epoxy resin, urethane acrylate resin, epoxy acrylate resin, cellulose resin, acetal resin, melamine resin, phenol resin, silicone resin , Polyester resin, polycarbonate resin, polyethylene resin, polystyrene resin, polyamide resin, polyimide resin, and mixtures thereof.

As the UV curable resin, a photopolymerizable prepolymer crosslinked and cured by UV light irradiation may be used, and examples of the photopolymerizable prepolymer include a cationic polymerization type and a radical polymerization type photopolymerizable prepolymer. Examples of the cationic polymerization type photopolymerizable prepolymer include an epoxy resin or a vinyl ester resin, and the epoxy resin includes a bisphenol type epoxy resin, a nobla type epoxy resin, an alicyclic epoxy resin, an aliphatic epoxy resin, and these And mixtures of. As the radical polymerization type photopolymerizable prepolymer, an acrylic prepolymer (hard prepolymer) having two or more acryloyl groups in one molecule and having a three-dimensional network structure through crosslinking curing may be preferably used from the viewpoint of hard coatability.

Examples of the acrylic prepolymer include urethane acrylate, polyester acrylate, epoxy acrylate, melamine acrylate, polyfluoroalkyl acrylate, silicone acrylate, and mixtures thereof. The urethane acrylate prepolymer can be obtained, for example, by esterifying a polyurethane oligomer obtained by reaction of a polyether polyol or a polyester polyol with a polyisocyanate through reaction with (meth)acrylic acid. The polyester acrylate-based prepolymer is, for example, esterified with (meth)acrylic acid or the hydroxyl group of a polyester oligomer having receivers at both ends obtained by condensation of a polyhydric carboxylic acid and a polyhydric alcohol, or alkylene oxide to a polyhydric carboxylic acid. It can be obtained by esterifying the hydroxyl group at the end of the oligomer obtained by adding a seed with (meth)acrylic acid. The epoxy acrylate-based prepolymer can be obtained, for example, by esterification of a relatively low molecular weight bisphenol type epoxy resin or an oxirane ring of a noblock epoxy resin with (meth)acrylic acid.

By adding different additives to the first hard coating layer and the second hard coating layer, an additional function required for each layer may be imparted. For example, the first hard coating layer may contain an antifouling agent to prevent fingerprints, stains, and scratches, and may have excellent surface hardness. In addition, the second hard coating layer may include a leveling agent and may function as a primer layer to facilitate mold formation or printing.

For example, the antifouling agent may be one or more selected from the group consisting of silicone polyether acrylate, polyether-modified acrylic functional siloxane, fluoropolyether, and fluoroacrylic compound, and the leveling agent may be a non-silicone acrylic compound. And it may be one or more selected from the group consisting of fluoroacrylic compounds.

The antifouling agent and the leveling agent may be added in an amount of 0.001% by weight to 3% by weight, or 0.01% by weight to 1% by weight based on the weight of the first hard coating layer and the second hard coating layer, respectively.

In addition, the first hard coating layer and the second hard coating layer may further include conventional additives such as antioxidants, light stabilizers, and photoinitiators.

As a specific example, the first hard coating layer and the second hard coating layer may include a urethane acrylate oligomer resin having 4 to 10 or 4 to 8 functional groups or a resin derived therefrom, and improving wear resistance. Hazardous organic silica and the like may be further included.

Specifically, the first hard coating layer and the second hard coating layer include a urethane acrylate oligomer resin having a thickness of 3 μm to 6 μm and a functional group of 6 to 10 or a resin derived therefrom.

In addition, both the first hard coating layer and the second hard coating layer may have excellent 3D moldability.

First adhesive layer and second adhesive layer

The first adhesive layer is disposed between the core substrate layer and the first sheet to improve bonding force therebetween and impart moldability. In addition, the second adhesive layer is disposed between the core substrate layer and the second sheet to improve bonding force therebetween and impart moldability.

The first adhesive layer and the second adhesive layer may have a thickness ratio of 1:0.5 to 1:1.5. When it is within the above range, the core substrate layer has a more symmetrical structure toward both sides around the core substrate layer, so that the occurrence of curl may be suppressed. More specifically, the first adhesive layer and the second adhesive layer may have a thickness ratio of 1: 0.9 to 1: 1.1.

The first adhesive layer and the second adhesive layer may have a thickness of 1 µm to 50 µm, 3 µm to 30 µm, 5 µm to 20 µm, 5 µm to 15 µm, 7 µm to 12 µm, or 8 µm to 12 µm. have.

Specifically, the first adhesive layer and the second adhesive layer may have a thickness of 5 μm to 15 μm. When it is within the above thickness range, it may be more advantageous in suppressing curl while having excellent interfacial adhesion.

The first adhesive layer and the second adhesive layer may include an adhesive resin, and may further include a curing agent and/or a photoinitiator.

The adhesive resin is not particularly limited, but may be, for example, a resin that can be cured by UV light irradiation, and accordingly, the first adhesive layer and the second adhesive layer may be prepared through UV curing. In addition, the adhesive resin may be a resin having good dispersibility of the UV absorber without being yellowed by UV light. For example, the adhesive resin includes polyester resin, acrylic resin, alkyd resin, amino resin, and the like. The adhesive resin may be used alone, or two or more types of copolymers or mixtures may be used. Among them, acrylic resins excellent in optical properties, weather resistance, adhesion to a substrate, and the like are preferable. In addition, the adhesive resin may be an optically transparent adhesive (optical clear adhesive, OCA).

The curing agent is not particularly limited as long as it is a material capable of curing the adhesive resin. Specifically, at least one type may be selected from the group consisting of an isocyanate curing agent, an epoxy curing agent, and an aziridine curing agent that are not yellowed by UV light. In addition, the curing agent may be included in 0.2 to 0.5% by weight, 0.3 to 0.5% by weight, 0.3 to 0.45% by weight, or 0.35 to 0.45% by weight, based on the weight of each of the first and second adhesive layers.

The photoinitiator is required for UV curing, for example, benzophenone-based, thioxanthone-based, α-hydroxy ketone-based, ketone-based, phenyl glyoxylate (phenyl glyoxylate) and acrylic phosphine oxide (acyl phosphine oxide) may be selected from one or more types from the group consisting of. The photoinitiator may be included in an amount of 0.1 to 5.0% by weight based on the weight of each of the first adhesive layer and the second adhesive layer.

Curl change and flexibility

The plastic laminate has very little change in curl at high temperatures.

For example, the plastic laminate may have a curl change of the edge within 3.0 mm, within 2.0 mm, within 1.0 mm, within 0.5 mm, or within 0.3 mm after being left at 140°C for 2 hours. Specifically, the plastic laminate has a change in curl of 0.3 mm or less in the corners after standing at 140° C. for 2 hours.

In addition, the plastic laminate may have a curl change of the edge within 3.0 mm, within 2.0 mm, within 1.0 mm, within 0.5 mm, or within 0.3 mm after being left at 100°C for 72 hours.

In addition, the plastic laminate may exhibit 7R or less, 6R or less, or 5R or less, and specifically 1R to 7R, or 3R to 6R when measuring bending using a mandrel tester or the like.

Embodiment of the laminated structure

According to one embodiment, the first sheet and the second sheet have a thickness ratio of 1: 0.9 to 1: 1.1, the core base layer has a thickness of 25 μm to 1000 μm, the first base layer and the The second base layer has a thickness of 10 μm to 500 μm, the first hard coat layer and the second hard coat layer have a thickness of 3 μm to 6 μm, and a urethane acrylate oligomer resin having 6 to 10 functional groups, or A resin derived therefrom is included, and after the plastic laminate is left at 140° C. for 2 hours, it has a curl change of 0.3 mm or less in the corners.

In addition, the plastic laminate may include a first adhesive layer disposed between the core substrate layer and the first sheet; And a second adhesive layer disposed between the core substrate layer and the second sheet, wherein the first hard coating layer and the second hard coating layer have a thickness ratio of 1: 0.9 to 1: 1.1, and the first substrate The layer and the second base layer may have a thickness ratio of 1: 0.9 to 1: 1.1, and the first adhesive layer and the second adhesive layer may have a thickness ratio of 1: 0.5 to 1: 1.5.

The total thickness of the plastic laminate may be 50 μm or more, 100 μm or more, or 150 μm or more, and may be 1000 μm or less, 500 μm or less, 300 μm or less, or 200 μm or less. Specifically, the total thickness of the plastic laminate is 50㎛ to 1000㎛, 100㎛ to 1000㎛, 200㎛ to 1000㎛, 300㎛ to 1000㎛, 400㎛ to 1000㎛, 500㎛ to 900㎛, 500㎛ to 750 It may be ㎛, 700㎛ to 900㎛, or 600㎛ to 900㎛.

Other constituent layers

In addition, as shown in FIG. 2, the plastic laminate may further include an adhesive layer 500 on one surface as needed to be applied as a front protective film attached to the front of the mobile device, and at this time, the adhesive layer The resin used may be the same as or similar to the first adhesive layer and the second adhesive layer described above.

In addition, in the plastic laminate, a release paper 600 may be further laminated to protect the surface of the adhesive layer 500. Examples of the material of the release layer include epoxy-based, epoxy-melamine-based, aminoalkyd-based, acrylic-based, melamine-based, silicone-based, fluorine-based, cellulose-based, urea resin-based, and polyolefin-based.

Optical properties

The plastic laminate may have optical properties for a front cover or a front protective film.

For example, the plastic laminate may have a high-order phase difference or almost no phase difference for controlling the optical axis to minimize optical interference, thereby enabling optical fingerprint recognition when applied as a front protective film or the like. Specifically, the plastic laminate may have a deviation of an orientation angle with respect to an in-plane direction (width direction, length direction, or any other direction) within ±10°, within ±5°, or within ±1°. As an example, the plastic laminate may have a deviation of the orientation angle with respect to the full width within ±10°, within ±5°, or within ±1°.

In addition, the plastic laminate may have an in-plane retardation (Re) of 300 nm or less, 200 nm or less, or 100 nm or less. In the case of a film with no or minimized retardation as described above, since the orientation angle with respect to the entire width is the same or similar, it is possible to recognize an optical fingerprint without considering the orientation angle.

To this end, the plastic laminate may include a high-order retardation film with a controlled optical axis or a film with a minimized retardation as a base layer, for example, the first base layer and the second base layer are ±10 with respect to the full width. It can have an orientation angle deviation within ˚, within ±5˚, or within ±1˚. In addition, the first base layer and the second base layer may have an in-plane retardation of 300 nm or less, 200 nm or less, or 100 nm or less.

In addition, the plastic laminate may have a total light transmittance of 80% or more, 85% or more, or 90% or more. Such total light transmittance can be measured according to a method such as JIS K7361.

In addition, the plastic laminate is not particularly limited in terms of color, but as an example, x and y values according to the CIE 1931 xy chromaticity space may be 0.2 to 0.4, respectively.

Surface properties

In addition, the plastic laminate may have excellent surface properties.

For example, the plastic laminate may have a pencil hardness of 1H or more, 2H or more, or 3H or more on the surface. Such pencil hardness can be measured according to a method such as ASTM D3363.

In addition, even if the plastic laminate is rubbed 100 or more, 200 or more, or 300 or more times with a 1.5 kg load in a steel wool abrasion test, the coating of the surface may not be damaged. In addition, even if the plastic laminate is rubbed 1500 or more, 2000 or more, or 2500 or more times with a 1.0 kg load in a steel wool wear test, the coating of the surface may not be damaged.

In addition, the plastic laminate may have a contact angle with respect to water of 80° to 130°, specifically 80° to 115°. Such a contact angle can be measured according to a method such as ASTM D5946.

In addition, when the plastic laminate is adhered to other substrates by an adhesive layer or the like, it may have an adhesive strength of 3B grade or higher, 4B grade or higher, or 5B grade or higher in a cross hatch cut test. Such a cross hatch cut test may be performed according to a method such as ASTM D3359.

Manufacturing method of plastic laminate

The method of manufacturing the plastic laminate may include forming a first hard coating layer on a first substrate layer to obtain a first sheet; Forming a second hard coating layer on the second base layer to obtain a second sheet; Laminating the first sheet on one surface of the core base layer so that the first base layer faces; And laminating the second sheet on the other surface of the core base layer so that the second base layer faces, wherein the first sheet and the second sheet have a thickness ratio of 1: 0.9 to 1: 1.1.

The plastic laminate thus produced has a configuration as described above. According to one embodiment, the first sheet and the second sheet have a thickness ratio of 1: 0.9 to 1: 1.1, the core base layer has a thickness of 25 μm to 1000 μm, the first base layer and the The second base layer has a thickness of 10 μm to 500 μm, the first hard coat layer and the second hard coat layer have a thickness of 3 μm to 6 μm, and a urethane acrylate oligomer resin having 6 to 10 functional groups, or A resin derived therefrom is included, and after the plastic laminate is left at 140° C. for 2 hours, it has a curl change of 0.3 mm or less in the corners.

Laminating a first sheet on one side of the core base layer and stacking a second sheet on the other side of the core base layer may be performed sequentially or simultaneously.

Preferably, the step of stacking the first sheet on one side of the core base layer and the step of stacking the second sheet on the other side of the core base layer are simultaneously performed to form a symmetrical structure to suppress the occurrence of curls. It can be more advantageous.

In addition, before the step of laminating a first sheet on one side of the core base layer and laminating a second sheet on the other side of the core base layer, one side of the core base layer And forming a first adhesive layer and a second adhesive layer on the other surface, respectively.

In this case, the first adhesive layer and the second adhesive layer may have a thickness ratio of 1:0.5 to 1:1.5.

The effect of plastic laminates

As described above, the plastic laminate according to the present invention includes a plastic film on which a hard coating layer is formed in a symmetrical structure, thereby minimizing the occurrence of curls even in a high temperature environment. In addition, the plastic laminate may further improve not only dimensional stability but also other properties such as antifouling properties and printability by adjusting the thickness, components, and process conditions of each layer. In particular, the plastic laminate may be used in various ways because of its thickness, mechanical and optical properties applicable to mobile devices manufactured in various standards in recent years.

Molded body

Further, the present invention provides a plastic molded article molded from the plastic laminate.

The plastic molded body molded from the plastic laminate has high durability and can be used in a variety of ways with the advantage of reducing cost due to multifunctional composite. Accordingly, the plastic molded body may be usefully applied as a front cover, a rear cover, or a front protective film of a mobile device by replacing a conventional glass material.

Such a plastic molded body may be manufactured from the plastic laminate by a process such as thermoforming, and during this molding process, not only curls are generated due to the layer-by-layer composition and composition of the plastic laminate, but also the curved portion of the edge. The occurrence of cracks can also be suppressed.

Hereinafter, the effect of suppressing the occurrence of curls at a high temperature by the symmetrical structure of the plastic laminate will be examined through an experimental example. However, the following experimental examples are only examples for examining the relationship between the symmetrical structure of the plastic laminate and the occurrence of curls at high temperature, and the scope of the present invention is not limited to the structure of the plastic laminate exemplified in these experimental examples.

In the following experimental examples, unless otherwise stated, a polyethylene terephthalate (PET) film was used as a V7610 product from SKC, and a CCL series product from I-component was used as a polycarbonate (PC) film.

Experimental Example 1

1A. Film production

PET films or PC films were prepared in various thicknesses of a single layer (Samples 1-1 to 1-7). In addition, a film in which two PET films or PC films were laminated was prepared (Samples 1-9 and 1-11).

In addition, a hard coating (HC) resin composition was coated on the PET film to a thickness of about 15 μm to prepare a hard coating film (Sample 1-8). At this time, the hard coating resin composition was prepared by mixing 47.6 parts by weight of a urethane acrylate oligomer type resin (MIRAMER PU620NT, Miwon), 1.7 parts by weight of a curing agent (Irgacure 184, Ciba), and 50.7 parts by weight of a solvent (toluene). The hard coating resin composition was coated on the surface of the substrate layer using a Mayer bar coater, etc., dried at 80° C. for 1 minute, and then UV-cured under ^{400 mJ/cm 2 conditions.}

In addition, two hard coat films prepared in this way were laminated so that their base layers contact each other (Samples 1-10). In the case of film lamination, an adhesive was applied to a thickness of about 5 μm on the abutting surface to adhere. UV-type acrylate resin (TS-03, NCP Chem) was used as an adhesive, and after applying the adhesive using a Mayer bar coater and laminating films with a laminator, UV curing under ^{400 mJ/cm 2 conditions} Made it.

1B. exam

In order to measure the initial curl of each prepared film sample, the maximum value of the raised heights of the four corners from the bottom of the film was measured. Thereafter, the film was heat-treated at 100° C. for 72 hours, and the curl was measured in the same manner. The curl change was calculated by subtracting the initial curl height from the curl height measured after the heat treatment.

The structures and evaluation results of the samples are shown in Table 1 below.

division Layer structure (adhesive layer omitted) Curl change Sample 1-1 PET(125㎛) 0mm Sample 1-2 PET(188㎛) 0mm Sample 1-3 PET(250㎛) 0.3mm Sample 1-4 PC(125㎛) 0mm Sample 1-5 PC(200㎛) 0mm Sample 1-6 PC(250㎛) 0mm Sample 1-7 PC(380㎛) 0mm Sample 1-8 HC(15㎛) / PET(188㎛) 34mm Sample 1-9 PET(188㎛) / PET(188㎛) 2mm Sample 1-10 HC(15㎛) / PET(188㎛) / PET(188㎛) / HC(15㎛) 3mm Sample 1-11 PC(200㎛) / PC(200㎛) 0mm

As shown in Table 1, the curl change of the hard coating film was greater than that of the PET or PC monolayer film. In addition, when two hard coating films were laminated in a symmetrical structure, the curl change was larger than that of the case where two PET or PC films were laminated, but the curl change was significantly less than that of a single hard coating film.

Experimental Example 2

2A. Film production

PET film or PC film was prepared in various thicknesses. The PET film and/or the PC film was laminated to prepare a film (Samples 2-2, 2-4, 2-6 to 2-10).

In addition, a hard coating (HC) resin composition was coated on the PET film to a thickness of about 15 μm to prepare a hard coating film, which was laminated with a PET film and/or a PC film (Samples 2-1, 2-3, 2-5). At this time, the preparation, coating and curing conditions of the hard coating resin composition were the same as in Experimental Example 1.

When the film was laminated, an adhesive was applied to the abutting surface to a thickness of about 5 μm, and the adhesive type, application and curing conditions were the same as in Experimental Example 1.

2B. exam

For each of the prepared film samples, the curl change was measured in the same manner as in Experimental Example 1, except that the heat treatment conditions were changed to 140°C and 2 hours.

The structure and evaluation results of the samples are shown in Table 2 below.

division Layer structure (adhesive layer omitted) Curl change Sample 2-1 HC(15㎛) / PET(250㎛) / PC(125㎛) / PET(250㎛) 13.0mm Sample 2-2 PET(250㎛) / PC(125㎛) / PET(250㎛) 11.5mm Sample 2-3 HC(15㎛) / PET(188㎛) / PC(250㎛) / PET(188㎛) 11.5mm Sample 2-4 PET(188㎛) / PC(250㎛) / PET(188㎛) 9.5mm Sample 2-5 HC(15㎛) / PET(125㎛) / PC(380㎛) / PET(125㎛) 7.5mm Sample 2-6 PET(125㎛) / PC(380㎛) / PET(125㎛) 7.0mm Sample 2-7 PET(250㎛) / PC(380㎛) 18.0mm Sample 2-8 PC(200㎛) / PET(250㎛) / PC(200㎛) 3.5mm Sample 2-9 PC(250㎛) / PC(300㎛) 2.5mm Sample 2-10 PET(250㎛) / PET(250㎛) 4.5mm

As shown in Table 2, when the upper/lower layers around the core layer have a symmetrical structure, the curl change is less. In addition, when the thickness of the PC film (core layer) was 380 µm and the thickness of the PET film (substrate layer) was 125 µm, the curl change was the least.

Experimental Example 3

3A. Film production

A hard coating (HC) resin composition was coated on a PET film to a thickness of about 15 μm to prepare a hard coating film, which was laminated with a PC film and a PET film (Sample 3-1). At this time, the preparation, coating and curing conditions of the hard coating resin composition were the same as in Experimental Example 1.

In addition, hard coating films were each laminated on both sides of the PC film as the center (Samples 3-2 to 3-5). At this time, the hard coating resin composition was diluted to change the thickness of the hard coating in the range of 9 μm to 15 μm.

When the film was laminated, an adhesive was applied to the abutting surface to a thickness of about 5 μm, and the adhesive type, application and curing conditions were the same as in Experimental Example 1.

3B. exam

For each of the prepared film samples, the curl change was measured in the same manner as in Experimental Example 1, except that the heat treatment conditions were changed to 140°C and 2 hours.

The structures and evaluation results of the samples are shown in Table 3 below.

division Layer structure (adhesive layer omitted) Curl change Sample 3-1 HC(15㎛) / PET(125㎛) / PC(380㎛) / PET(125㎛) 7.5mm Sample 3-2 HC(15㎛) / PET(125㎛) / PC(380㎛) / PET(125㎛) / HC(15㎛) 5.5mm Sample 3-3 HC(13㎛) / PET(125㎛) / PC(380㎛) / PET(125㎛) / HC(13㎛) 5.5mm Sample 3-4 HC(11㎛) / PET(125㎛) / PC(380㎛) / PET(125㎛) / HC(11㎛) 4.5mm Sample 3-5 HC(9㎛) / PET(125㎛) / PC(380㎛) / PET(125㎛) / HC(9㎛) 3.5mm

As shown in Table 3, when a hard coating film is stacked above and below the core layer (PC film), there is little change in curl. In addition, the smaller the thickness of the hard coating layer, the smaller the curl change.

Experimental Example 4

4A. Film production

A hard coating film was prepared by coating a hard coating (HC) resin composition to a thickness of about 9 μm on a PET film. At this time, in Samples 4-1 to 4-3, the following hard coating (HC) resin compositions were used, respectively. In addition, the coating and curing conditions of the hard coating resin composition were the same as in Experimental Example 1.

-Sample 4-1: urethane acrylate oligomer type resin (solid content 100% by weight, MIRAMER PU620NT, Miwon) 25.4 parts by weight, curing agent (Irgacure 184, Ciba) 1.7 parts by weight, and solvent (toluene) 50.2 parts by weight

-Sample 4-2: Urethane acrylate oligomer type resin (solid content 70% by weight, D7, Miwon) 47.6 parts by weight, curing agent (Irgacure 184, Ciba company) 1.7 parts by weight, and solvent (toluene) 50.7 parts by weight

-Sample 4-3: Urethane acrylate oligomer type resin (solid content 100% by weight, D9, Miwon) 25.4 parts by weight, curing agent (Irgacure 184, Ciba company) 1.7 parts by weight, and solvent (toluene) 50.2 parts by weight

Hard coating films were each laminated on both sides with the PC film as the center. In the case of film lamination, an adhesive was applied to the abutting surface to a thickness of about 5 μm, and the adhesive type, application and curing conditions were the same as in Experimental Example 1.

4B. exam

For each of the prepared film samples, the curl change was measured in the same manner as in Experimental Example 1, except that the heat treatment conditions were changed to 140°C and 2 hours.

The structures and evaluation results of the samples are shown in Table 4 below.

division Layer structure (adhesive layer omitted) Curl change Sample 4-1 HC(9㎛) / PET(188㎛) / PC(380㎛) / PET(188㎛) / HC(9㎛) 3.5mm Sample 4-2 HC(9㎛) / PET(188㎛) / PC(380㎛) / PET(188㎛) / HC(9㎛) 2.0mm Sample 4-3 HC(9㎛) / PET(188㎛) / PC(380㎛) / PET(188㎛) / HC(9㎛) 2.5mm

As shown in Table 4, it was confirmed that the curl change was changed according to the composition of the hard coating layer. Specifically, the resin (MIRAMER PU620NT) used for the hard coating layer in Sample 4-1 is an oligomer for high hardness hard coating with 6 functional groups, and the resin (D7) used for the hard coating layer in Sample 4-2 is a flexible hard coating layer having 9 functional groups. As a coating oligomer, when the hardness of the resin generally used in the hard coating layer is high, the abrasion resistance is high, but the occurrence of curls and cracks increases, whereas when the hardness of the resin is low, the abrasion resistance is low, but the occurrence of curls and cracks tends to decrease. . On the other hand, the resin (D9) used for the hard coating layer in Sample 4-3 was an oligomer for flexible hard coating having 6 functional groups. By introducing organic silica, it was possible to reduce the occurrence of curls and cracks while improving abrasion resistance.

Experimental Example 5

5A. Film production

A hard coating (HC) resin composition was coated on the PET film to a thickness of about 9 μm to prepare a hard coating film. At this time, the hard coating resin composition is a urethane acrylate oligomer type resin (solid content 70% by weight, D7, Miwon) 47.6 parts by weight, a curing agent (Irgacure 184, Ciba) 1.7 parts by weight, and a solvent (toluene) 50.7 parts by weight by mixing Was manufactured. The coating and curing conditions of the hard coating resin composition were the same as in Experimental Example 1.

Hard coating films were each laminated on both sides with the PC film as the center. In the case of film lamination, the adhesive was applied by applying different thicknesses within the range of 5 μm to 10 μm on the abutting surface, and other types of adhesives, application and curing conditions were the same as in Experimental Example 1.

5B. exam

For each of the prepared film samples, the curl change was measured in the same manner as in Experimental Example 1, except that the heat treatment conditions were changed to 140°C and 2 hours.

The structure and evaluation results of the samples are shown in Table 5 below.

division Layer structure (adhesive layer omitted) Adhesive thickness Curl change Sample 5-1 HC(9㎛) / PET(188㎛) / PC(380㎛) / PET(188㎛) / HC(9㎛) 5㎛ 2.0mm Sample 5-2 HC(9㎛) / PET(188㎛) / PC(380㎛) / PET(188㎛) / HC(9㎛) 7㎛ 1.0mm Sample 5-3 HC(9㎛) / PET(188㎛) / PC(380㎛) / PET(188㎛) / HC(9㎛) 10㎛ 0.5mm

As shown in Table 5, it was confirmed that the curl change was changed according to the thickness of the adhesive layer.

Experimental Example 6

6A. Film production

A hard coating (HC) resin composition was coated on a PET film with different thicknesses within the range of 6 μm to 9 μm to prepare a hard coating film. At this time, the following hard coating (HC) resin compositions were used in Samples 6-1 to 6-3, respectively. In addition, the coating and curing conditions of the hard coating resin composition were the same as in Experimental Example 1.

-Sample 6-1: Urethane acrylate oligomer type resin (solid content 70% by weight, D7, Miwon) 47.6 parts by weight, curing agent (Irgacure 184, Ciba company) 1.7 parts by weight, and solvent (toluene) 50.7 parts by weight

-Sample 6-2: Urethane acrylate oligomer type resin (solid content 70% by weight, D7, Miwon) 47.6 parts by weight, curing agent (Irgacure 184, Ciba company) 1.7 parts by weight, and solvent (toluene) 56.8 parts by weight

-Sample 6-3: Urethane acrylate oligomer type resin (solid content 70% by weight, D7, Miwon) 47.6 parts by weight, curing agent (Irgacure 184, Ciba company) 1.7 parts by weight, and solvent (toluene) 60.0 parts by weight

Hard coating films were each laminated on both sides with the PC film as the center. When laminating the film, an adhesive was applied to the abutting surface to a thickness of about 10 μm, and the adhesive type, application and curing conditions were the same as in Experimental Example 1.

6B. exam

For each of the prepared film samples, the curl change was measured in the same manner as in Experimental Example 1, except that the heat treatment conditions were changed to 140°C and 2 hours.

The structures and evaluation results of the samples are shown in Table 6 below.

division Layer structure (adhesive layer omitted) Curl change Sample 6-1 HC(9㎛) / PET(188㎛) / PC(380㎛) / PET(188㎛) / HC(9㎛) 0.5mm Sample 6-2 HC(7㎛) / PET(188㎛) / PC(380㎛) / PET(188㎛) / HC(7㎛) 0.5mm Sample 6-3 HC(6㎛) / PET(188㎛) / PC(380㎛) / PET(188㎛) / HC(6㎛) 0.0mm

As shown in Table 6, it was confirmed that the curl change was changed according to the thickness of the hard coating layer.

Experimental Example 7

7A. Film production

A hard coating film was prepared by coating a hard coating (HC) resin composition to a thickness of 6 μm on the PET film. At this time, the hard coating (HC) resin composition below was used for the front/rear hard coating layers of Samples 7-1 and 7-2, respectively. In addition, the coating and curing conditions of the hard coating resin composition were the same as in Experimental Example 1.

-Front/rear hard coating layer of Sample 7-1: Urethane acrylate oligomer type resin (solid content 70% by weight, D7, Miwon) 47.6 parts by weight, hardener (Irgacure 184, Ciba) 1.7 parts by weight, and solvent (toluene) 60.0 parts by weight

-Front hard coating layer of Sample 7-2: Urethane acrylate oligomer type resin (solid content 70% by weight, D7, Miwon) 47.6 parts by weight, hardener (Irgacure 184, Ciba) 1.7 parts by weight, antifouling agent (KY-1203, ShinEtsu) 0.2 parts by weight and solvent (toluene) 60.0 parts by weight

-Rear hard coating layer of Sample 7-2: Urethane acrylate oligomer type resin (solid content 70% by weight, D7, Miwon) 47.6 parts by weight, leveling agent (Flow-300; TEGO) 1.7 parts by weight and solvent (toluene) 60.0 Parts by weight

Hard coating films were each laminated on both sides with the PC film as the center. When laminating the film, an adhesive was applied to the abutting surface to a thickness of about 10 μm, and the adhesive type, application and curing conditions were the same as in Experimental Example 1.

7B. exam

For each prepared film sample, the hard coating layer was evaluated as follows.

-Front hard coating layer: Measurement of contact angle with water

-Back hard coating layer: Surface tension measurement using Dyne pen (Acrotest)

The structure and evaluation results of the samples are shown in Table 7 below.

division Layer structure (adhesive layer omitted) Contact angle Surface tension Sample 7-1 HC(6㎛) / PET(188㎛) / PC(380㎛) / PET(188㎛) / HC(6㎛) 53˚ ≤26 dyne Sample 7-2 HC(6㎛) / PET(188㎛) / PC(380㎛) / PET(188㎛) / HC(6㎛) 110˚ 30 dyne

As shown in Table 7, the water contact angle was increased by adding an antifouling agent to the front hard coating layer, and thus, contamination prevention or anti-fingerprint properties may be exhibited on the entire surface exposed to the outside. In addition, the surface tension was increased by adding a leveling agent to the rear hard coating layer, and in this case, it may be easy to form a mold for decoration or print a design.

Experimental Example 8

8A. Film production

Sample 4-1 prepared in Experimental Example 4 and Sample 7-1 prepared in Experimental Example 7 were prepared.

8B. exam

Curling was observed while performing thermoforming on the prepared sample. Specifically, molding was evaluated under the following conditions using a heating molding apparatus (SHT-HTFC 001, Sungho Tech Co., Ltd.).

1) Molding temperature: 140℃

2) Molding time: preheating (10 seconds), molding (15 seconds), cooling (60 seconds)

3) Heat forming jig: size (72.5mm x 155mm), edge curvature (4R)

The structures and evaluation results of the samples are shown in Table 8 below.

division Layer structure (adhesive layer omitted) Curl type Curl change Sample 4-1 HC(9㎛) / PET(188㎛) / PC(380㎛) / PET(188㎛) / HC(9㎛) Torsion curl ≥5mm Sample 7-1 HC(6㎛) / PET(188㎛) / PC(380㎛) / PET(188㎛) / HC(6㎛) No curl 0mm

As shown in Table 8, sample 7-1 did not cause curling during heat molding. In addition, in the case of Sample 7-1, no cracks were found in the hard coating layer after heat molding, but in Sample 4-1, a number of cracks were found in the hard coating layer at the edge portion.

Experimental Example 9

9A. Film production

Samples 6-1 to 6-3 prepared in Experimental Example 6 were prepared as films having different thicknesses of the hard coating layers.

9B. exam

For the prepared sample, bending evaluation was performed using an Elcometer cylindrical mandrel tester (model name: K1506M201). In addition, it was observed whether cracks occurred while performing heat molding on the prepared sample. At this time, the heating molding conditions were carried out in the same manner as in Experimental Example 8. The thickness and evaluation results of the hard coating layer of the samples are shown in Table 9 below.

division Hard coating layer thickness Flexibility Whether cracks have occurred Sample 6-1 HC(9㎛) 8R Edge crack Sample 6-2 HC(7㎛) 6R No crack Sample 6-3 HC(6㎛) 5R No crack

As shown in Table 9, it was confirmed that the molding properties were changed according to the thickness of the hard coating layer. In particular, Sample 6-3 having a hard coating layer having a thickness of 6 μm was the most excellent in flexibility and no cracks occurred during heat molding.

Experimental Example 10

10A. Film production

As a PET film, products of various thicknesses (50㎛, 75㎛, 100㎛) manufactured by SKC (V7610) were prepared, and products of various thicknesses (30㎛, 50㎛) manufactured by SKC HT&M as a PC film were prepared. Ready.

A hard coating film was prepared by coating a hard coating (HC) resin composition to a thickness of about 6 μm on a PET film. At this time, the hard coating resin composition of Sample 6-3 used in Experimental Example 6 was used as the hard coating resin composition, and the coating and curing conditions of the other hard coating resin composition were the same as in Experimental Example 1.

Hard coating films were each laminated on both sides with the PC film as the center. When laminating the film, an adhesive was applied to the abutting surface to a thickness of about 10 μm, and the adhesive type, application and curing conditions were the same as in Experimental Example 1.

10B. exam

The curl change was measured in the same manner as in Experimental Example 1, except that the heat treatment conditions for the prepared sample were changed to 140°C and 2 hours. The structure and evaluation results of the samples are shown in Table 10 below.

division Layer structure (adhesive layer omitted) Curl change Sample 10-1 HC(6㎛) / PET(50㎛) / PC(30㎛) / PET(50㎛) / HC(6㎛) ≒ 0mm Sample 10-2 HC(6㎛) / PET(50㎛) / PC(50㎛) / PET(50㎛) / HC(6㎛) ≒ 0mm Sample 10-3 HC(6㎛) / PET(75㎛) / PC(30㎛) / PET(75㎛) / HC(6㎛) ≒ 0mm Sample 10-4 HC(6㎛) / PET(75㎛) / PC(50㎛) / PET(75㎛) / HC(6㎛) ≒ 0mm Sample 10-5 HC(6㎛) / PET(100㎛) / PC(30㎛) / PET(100㎛) / HC(6㎛) ≒ 0mm Sample 10-6 HC(6㎛) / PET(100㎛) / PC(50㎛) / PET(100㎛) / HC(6㎛) ≒ 0mm

As shown in Table 10, the laminates (Samples 10-1 to 10-6) of a symmetrical structure in which the thickness of the hard coating layer is 6 μm, even if the thickness of the PET film and the PC film is 100 μm or less, No curl change was observed at high temperatures.

Experimental Example 11

11A. Film production

As a PET film, a high-order phase difference PET film with controlled optical axis (TU08, SKC) and a PET film with minimized phase difference (TOF40, SKC) were prepared in various thicknesses (40㎛, 55㎛, 80㎛), and as a PC film. Products of various thicknesses (30㎛, 50㎛) manufactured by SKC HT&M were prepared.

A hard coating film was prepared by coating a hard coating (HC) resin composition to a thickness of about 6 μm on a PET film. At this time, the hard coating resin composition of Sample 6-3 used in Experimental Example 6 was used as the hard coating resin composition, and the coating and curing conditions of the other hard coating resin composition were the same as in Experimental Example 1.

Using this, a laminate with a PC film was prepared as follows or left as a single hard coating film. When laminating the film, an adhesive was applied to the abutting surface to a thickness of about 10 μm, and the adhesive type, application and curing conditions were the same as in Experimental Example 1.

-Samples 11-1 to 11-4: A hard coating film was prepared using a PET film with a controlled optical axis, and a hard coating film was laminated on both sides with a PC film as the center.

-Samples 11-5 and 11-6: A hard coating film was prepared using a PET film with a minimized retardation, and a hard coating film was laminated on both sides with a PC film as the center.

-Samples 11-7 and 11-8: Hard coating film was prepared using high-order PET film with controlled optical axis

-Sample 11-9: A hard coating film was produced using PET film with minimized retardation.

10B. exam

Molding evaluation was performed on the prepared sample in the same manner as in Experimental Example 8 through a heat molding method. The structure and evaluation results of the samples are shown in Table 11 below.

division Layer structure (adhesive layer omitted) Curl type Curl change Sample 11-1 HC(6㎛) / PET(55㎛) / PC(30㎛) / PET(55㎛) / HC(6㎛) No curl ≒ 0mm Sample 11-2 HC(6㎛) / PET(55㎛) / PC(50㎛) / PET(55㎛) / HC(6㎛) No curl ≒ 0mm Sample 11-3 HC(6㎛) / PET(80㎛) / PC(30㎛) / PET(80㎛) / HC(6㎛) No curl ≒ 0mm Sample 11-4 HC(6㎛) / PET(80㎛) / PC(50㎛) / PET(80㎛) / HC(6㎛) No curl ≒ 0mm Sample 11-5 HC(6㎛) / PET(40㎛) / PC(30㎛) / PET(40㎛) / HC(6㎛) No curl ≒ 0mm Sample 11-6 HC(6㎛) / PET(40㎛) / PC(50㎛) / PET(40㎛) / HC(6㎛) No curl ≒ 0mm Sample 11-7 HC(6㎛) / PET(55㎛) Torsion curl ≥ 3mm Sample 11-8 HC(6㎛) / PET(80㎛) Torsion curl ≥ 3mm Sample 11-9 HC(6㎛) / PET(40㎛) Torsion curl ≥ 3mm

As shown in Table 11, the symmetrical laminates (Samples 11-1 to 11-6) in which the thickness of the hard coating layer is 6 μm, even if the thickness of the PET film and the PC film is 100 μm or less, It can be seen that it is molded into a good shape without causing curls during heat molding. In particular, since these laminates have a PET film whose optical axis is controlled or phase difference is minimized, there is little optical interference, so there is no problem in utilizing functions such as optical fingerprint recognition in mobile devices.

On the other hand, a single hard coating film (Samples 11-7 to 11-9) may be difficult to apply to the front or rear cover of mobile devices that require bending molding due to torsion curls occurring during heat molding. It may not be particularly necessary or may be applicable as a front protective film bonded to the cover with an adhesive.

Since the plastic molded body molded from the plastic laminate according to the present invention has high durability and can be used in various ways with the advantage of reducing costs due to multi-functional composites, it can replace the conventional glass material to cover the front or rear of the mobile device or It can be applied as a front protective film.

10: first sheet, 20: second sheet,
100: core substrate layer, 210: first substrate layer,
220: second base layer, 310: first hard coating layer,
320: second hard coating layer, 410: first adhesive layer,
420: second adhesive layer, 500: adhesive layer,
600: Hyungji Lee.

Claims (14)

Core base layer;
A first sheet including a first substrate layer and a first hard coating layer sequentially disposed on one surface of the core substrate layer; And
A plastic laminate comprising a second sheet including a second base layer and a second hard coating layer sequentially disposed on the other surface of the core base layer,
The first sheet and the second sheet have a thickness ratio of 1: 0.9 to 1: 1.1, the core base layer has a thickness of 25 µm to 100 µm, and the first base layer and the second base layer have 10 Has a thickness of µm or more, and the first and second base layers have an orientation angle deviation within ±1° or an in-plane retardation of 100 nm or less with respect to the full width, and the first hard coating layer and the second hard coating layer A urethane acrylate oligomer resin having a thickness of 3 μm to 6 μm and a functional group of 6 to 10 or a resin derived therefrom, and the total thickness of the plastic laminate is 200 μm or less, and the plastic laminate is After standing at 140° C. for 2 hours, the plastic laminate has a change in the height of within 0.3 mm at the corners.
The method of claim 1,
The plastic laminate, wherein the first base layer and the second base layer have a thickness of 10 μm to 100 μm.
delete delete The method of claim 1,
The plastic laminate has a pencil hardness of 3H or more on the surface and a contact angle of 80˚ to 130˚ with respect to water, the plastic laminate.
The method of claim 1,
The first hard coating layer and the second hard coating layer further comprises an organic silica, plastic laminate.
The method of claim 1,
The plastic laminate
A first adhesive layer disposed between the core substrate layer and the first sheet; And
Further comprising a second adhesive layer disposed between the core substrate layer and the second sheet,
The first adhesive layer and the second adhesive layer has a thickness ratio of 1: 0.5 to 1: 1.5, the plastic laminate.
The method of claim 1,
The core substrate layer, the first substrate layer, and the second substrate layer each contain polycarbonate, polyethylene terephthalate (PET), polycyclohexylenedimethylene terephthalate (PCT), or alloy resins thereof,
The first hard coating layer contains an antifouling agent, and the second hard coating layer contains a leveling agent.
The method of claim 8,
The antifouling agent is at least one selected from the group consisting of silicone polyether acrylate, polyether-modified acrylic functional siloxane, fluoropolyether, and fluoroacrylic compound,
The leveling agent is at least one selected from the group consisting of non-silicone acrylic compounds and fluoroacrylic compounds, the plastic laminate.
The method of claim 1,
A first adhesive layer in which the plastic laminate is disposed between the core substrate layer and the first sheet; And a second adhesive layer disposed between the core substrate layer and the second sheet,
The first hard coating layer and the second hard coating layer have a thickness ratio of 1: 0.9 to 1: 1.1, the first base layer and the second base layer have a thickness ratio of 1: 0.9 to 1: 1.1, the second 1 adhesive layer and the second adhesive layer have a thickness ratio of 1: 0.5 to 1: 1.5,
The first adhesive layer and the second adhesive layer has a thickness of 5㎛ to 15㎛, the plastic laminate.
Forming a first hard coating layer on the first base layer to obtain a first sheet;
Forming a second hard coating layer on the second base layer to obtain a second sheet;
Laminating the first sheet on one side of the core base layer so that the first base layer faces; And
A method for manufacturing a plastic laminate comprising the step of laminating the second sheet so that the second base layer faces on the other surface of the core base layer,
The first sheet and the second sheet have a thickness ratio of 1: 0.9 to 1: 1.1, the core base layer has a thickness of 25 µm to 100 µm, and the first base layer and the second base layer have 10 Has a thickness of µm or more, and the first and second base layers have an orientation angle deviation within ±1° or an in-plane retardation of 100 nm or less with respect to the full width, and the first hard coating layer and the second hard coating layer A urethane acrylate oligomer resin having a thickness of 3 μm to 6 μm and a functional group of 6 to 10 or a resin derived therefrom, and the total thickness of the plastic laminate is 200 μm or less, and the plastic laminate is After standing at 140° C. for 2 hours, a method of manufacturing a plastic laminate having a change in curl of a height of 0.3 mm or less at the corners.
The method of claim 11,
Laminating a first sheet on one side of the core base layer and stacking a second sheet on the other side of the core base layer at the same time, a method of manufacturing a plastic laminate.
A plastic molded article molded from the plastic laminate of claim 1.
The method of claim 13,
The plastic molded body is applied as a front cover, a rear cover, or a front protective film of a mobile device.

Images