KR20200064275A - Electromagnetic wave transmitting cover and method of manufacturing thereof - Google Patents

Abstract

Provided is an electromagnetic wave transmitting cover which comprises a transparent resin layer, a transfer laminate, a metal layer, and a base layer, wherein the transfer laminate comprises: an adhesive layer comprising a base resin and nano-silica, and attached to the transparent resin layer; a release layer comprising an acrylic resin and nano-silica; and a colored layer stacked between the adhesive layer and the release layer. The present invention can maximize print matching with improved cutting properties and adhesion properties.

Description

Electromagnetic wave transmission cover and its manufacturing method{ELECTROMAGNETIC WAVE TRANSMITTING COVER AND METHOD OF MANUFACTURING THEREOF}

The present invention relates to an electromagnetic wave transmission cover and a method for manufacturing the same.

The auto cruise control system is a technology that measures the inter-vehicle distance or relative speed between the vehicle in front and the host vehicle by a sensor mounted on the front of the vehicle, controls the brakes based on this information, and controls the inter-vehicle distance while accelerating/decelerating the host vehicle. As a sensor used in an auto cruise control system, a radar device, which is an electromagnetic wave transmitting and receiving device such as a millimeter wave radar, is generally used.

The radar device mounted on the front of the vehicle body is generally disposed behind the front grill, and the front grill is generally equipped with an emblem or ornament of the vehicle manufacturer. The millimeter wave irradiated from the radar device is radiated to the front through the front grill or emblem, reflected from an object such as a vehicle in front or an obstacle, and the reflected light is returned to the radar device through the front grill or the like. Therefore, a portion located in the beam path of a radar device such as a front grill or an emblem has a low electromagnetic wave transmission loss, and an electromagnetic wave transmission cover capable of providing a desired aesthetic is required.

An object of the present invention is to provide an electromagnetic wave transmission cover that exhibits excellent electromagnetic wave transmittance with excellent print matching and adhesion.

It is also an object of the present invention to provide a method for manufacturing the electromagnetic wave transmission cover.

The objects of the present invention are not limited to the above-mentioned objects, and other objects and advantages of the present invention not mentioned can be understood by the following description, and will be more clearly understood by embodiments of the present invention. In addition, it will be readily appreciated that the objects and advantages of the present invention can be realized by means of the appended claims and combinations thereof.

A transparent resin layer, a transfer laminate, a metal layer and a base layer according to the present invention, the transfer laminate comprising a base resin and nano silica and an adhesive layer attached to the transparent resin layer; A release layer comprising an acrylic resin and nano silica; And a colored layer stacked between the adhesive layer and the release layer.

In addition, the step of laminating the transfer laminate on the carrier film according to the present invention; Injection molding a transparent resin layer having irregularities; Laminating a transfer laminate laminated on the carrier film on a transparent resin layer having the uneven portion, and transferring the transfer laminate by a hot stamp process; Forming a metal layer on the transfer laminate; And forming a base layer on the metal layer, wherein the transfer laminate includes a base resin and nano silica and an adhesive layer attached to the transparent resin layer; A release layer comprising an acrylic resin and nano silica; And a colored layer stacked between the adhesive layer and the release layer.

The electromagnetic wave transmission cover according to the present invention exhibits excellent radar transmittance and can maximize print matching with improved cutting and adhesion while expressing excellent design similar to an emblem or front grill.

In addition to the above-described effects, the concrete effects of the present invention will be described together while describing the specific matters for carrying out the invention.

1 is a schematic cross-sectional view of an electromagnetic wave transmission cover according to an embodiment of the present invention.
2 is a method of manufacturing an electromagnetic wave transmission cover according to an embodiment of the present invention, the transfer laminate laminated on the carrier film is laminated on the convex portion of the transparent resin layer having irregularities, and stamped on the carrier film It is a schematic sectional view showing a member being placed and pressed.
3 is a schematic cross-sectional view showing that the transfer laminate is transferred to the transparent resin layer after separating the stamp member and removing the carrier film in the method of manufacturing the electromagnetic wave transmission cover according to the embodiment of the present invention.
Figure 4 shows the measurement results of the cutting properties of Examples 1 to 3.
5 shows the measurement results of the cutability of Comparative Example 1.

The above-described objects, features, and advantages will be described in detail below with reference to the accompanying drawings, and accordingly, a person skilled in the art to which the present invention pertains can easily implement the technical spirit of the present invention. In the description of the present invention, when it is determined that detailed descriptions of known technologies related to the present invention may unnecessarily obscure the subject matter of the present invention, detailed descriptions will be omitted. Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. The same reference numerals in the drawings are used to indicate the same or similar components.

In the following, the arrangement of any component in the "upper (or lower)" or "upper (or lower)" of the component means that the arbitrary component is disposed in contact with the upper surface (or lower surface) of the component. In addition, it may mean that other components may be interposed between the component and any component disposed on (or under) the component.

One embodiment of the present invention includes a transparent resin layer, a transfer laminate, a metal layer and a base layer, the transfer laminate includes a base resin and nano silica and an adhesive layer attached to the transparent resin layer; A release layer comprising an acrylic resin and nano silica; And a colored layer laminated between the adhesive layer and the release layer.

The radar device is a device that can measure the inter-vehicle distance or relative speed between the front vehicle and the host vehicle by irradiating the millimeter wave (76GHz to 77GHz), control the brake based on this information, and control the inter-vehicle distance while accelerating and decelerating the host vehicle. The electromagnetic wave transmission cover is located between the radar device and the front grill mounted on the front of the vehicle body or between the radar device and the emblem, and is required to have low electromagnetic wave transmission loss. In addition, the electromagnetic wave transmission cover is used in a design similar to the emblem or front grill, and it is required to exhibit excellent design by giving continuity to the metallic luster represented by the emblem or front grill.

The design of the electromagnetic wave transmission cover can be roughly divided into a metal expression part and a part expressing shade. The electromagnetic wave transmission cover is a molded product having a complex three-dimensional structure according to the shape or emblem of the front grill convexly located in front of the vehicle, and matching the metal color of the front grill and/or the emblem and the dark color around the printing Last name is important. When the print matching property of the electromagnetic wave transmission cover is inferior, there is a problem that design is deteriorated.

1 is a schematic cross-sectional view of an electromagnetic wave transmission cover according to an embodiment of the present invention, wherein the electromagnetic wave transmission cover includes a transparent resin layer, a transfer laminate, a metal layer and a base layer, and the transfer laminate is a base resin And an adhesive layer comprising nano silica and attached to the transparent resin layer. A release layer comprising an acrylic resin and nano silica; And a colored layer stacked between the adhesive layer and the release layer, thereby improving print matching and exhibiting excellent electromagnetic wave transmission. In addition, the electromagnetic wave transmission cover can improve weather resistance by exhibiting excellent water resistance, moisture resistance, heat resistance, and salt water resistance with excellent adhesion between interfaces.

The electromagnetic wave transmission cover includes a transparent resin layer, a transfer laminate, a metal layer and a base layer. Specifically, the transparent resin layer may have an uneven portion. The electromagnetic wave transmission cover may have a three-dimensional shape having an uneven portion by injection molding a transparent resin layer located adjacent to the front grill.

The transparent resin layer may include one resin selected from the group consisting of polymethyl methacrylate (PMMA), polycarbonate (PC), and combinations thereof.

The transparent resin layer serves as a support in the electromagnetic wave transmission cover, including the resin, so that the metallic luster of the metal layer can be recognized well outside the vehicle, irradiated from a radar device, and reflected and returned from the object It can exhibit excellent transmittance to electromagnetic waves.

The electromagnetic wave transmission cover includes a transfer laminate including an adhesive layer, a colored layer, and a release layer on one surface of the transparent resin layer. The transfer laminate may be a transfer material attached to an iron portion of the transparent resin layer by a hot stamp process. Specifically, as described later, the transfer laminate is laminated on a transparent resin layer having the uneven portion, and the heat transfer and pressure are applied by a hot stamp process to apply an iron portion of the transparent resin layer, as described later. After attaching to ), it may be formed by peeling the carrier film. Specifically, the transfer laminate may be formed by peeling together the carrier film when the carrier film is peeled, and the remaining transfer laminates covering the main parts excluding the transfer laminate attached to the iron portion of the transparent resin layer are peeled off together with the carrier film. have. At this time, if the cutability between the transfer laminate attached to the iron portion of the transparent resin layer and the transfer laminate covering the recess is low, or if the adhesion between the transparent resin layer, the transfer laminate and the base layer is low, , Print matching performance may deteriorate and design may deteriorate. In addition, if the adhesion is low, interlayer peeling may occur due to hot heat inside the vehicle, and rainwater, seawater, etc. may enter or deteriorate weather resistance between the interfaces between the layers of the electromagnetic wave transmission cover. In the present invention, the iron portion of the transparent resin layer means a portion of the surface on which the transfer laminate is in contact with the transparent resin layer, and the main portion refers to a portion covered by the transfer laminate on the extension line of the iron portion without the transfer laminate being contacted.

The transfer laminate includes a base resin and nano silica, and an adhesive layer attached to the transparent resin layer; A release layer comprising an acrylic resin and nano silica; And a colored layer laminated between the adhesive layer and the release layer. The electromagnetic wave transmission cover can maximize the print matching property by improving the cutting property while expressing an excellent shading feeling through the composition of the release layer and the adhesive layer of the transfer laminate. In addition, the electromagnetic wave transmission cover may exhibit excellent water resistance, moisture resistance, heat resistance, and salt water resistance with excellent adhesion, thereby improving weather resistance.

The release layer includes acrylic resin and nano silica. The release layer contains an acrylic resin, and does not peel off integrally with the carrier film when peeling the carrier film, and may remain attached to one surface of the colored layer.

Generally, the composition of the release layer contains a wax component, and when the carrier film and the release layer are peeled off, wax components are present on both sides. When the release layer and the pigment foil are transferred from the carrier film, and then a metal-like film expressing metallicity is adhered to the release layer in which the wax component is present, there is a problem in that the interfacial adhesion is reduced due to the low surface free energy of the wax component. .

The release layer may include a polymethyl methacrylate-based resin to facilitate adhesion to a metal layer that is the next step, that is, a metal-like composite film, without deteriorating surface free energy.

Specifically, the glass transition temperature (Tg) of the acrylic resin may be about 100 ℃ to about 115 ℃. The release layer may include an acrylic resin having a glass transition temperature within the above range to improve print matching by imparting excellent heat resistance, cutting properties and design properties. The glass transition temperature can be measured using differential scanning calorimetry (DSC).

More specifically, when the glass transition temperature of the acrylic resin is less than the above range, it is not suitable for a hot stamping process due to lack of heat resistance, and may not peel off from the carrier film. And, when it exceeds the above range, the release force is too low, the cutability of the transfer laminate is reduced, there may be a problem that ribs are formed on the surface of the release layer. And, when the viscosity is increased to apply the same thickness, there may be a problem that the appearance of the coating is lowered.

In addition, the weight average molecular weight of the acrylic resin of the release layer may be about 40,000 g/mol to about 70,000 g/mol. The release layer may include an acrylic resin having a weight average molecular weight within the above range, and exhibit excellent peelability and cutability. The weight average molecular weight can be measured using gel permeation chromatography (Gel Permeation Chromatography, GPC).

Specifically, when the weight average molecular weight of the acrylic resin is less than the above range, the peelability with the carrier film and the cutability of the transfer laminate may be reduced, and the coating film stability may be reduced, such as cracks on the surface of the transfer laminate. Can be. In addition, when the weight average molecular weight of the acrylic resin exceeds the above range, when the carrier film is peeled off, the release layer is stretched to generate a lot of burrs, and there is a problem that the release layer surface is not uniformly formed due to the increase in viscosity. It can be. For example, the acrylic resin may be polymethyl methacrylate, which is a polymer of methyl methacrylate.

In addition, the release layer includes nano-silica together with the acrylic resin. The release layer is not a wax component, but can include nano silica to ensure transparency, and impart appropriate surface free energy. And, it is possible to improve the adhesion to the metal layer, that is, the metal-like composite film. For example, the secondary force with the adhesive layer of the metal-like composite film can be improved.

The nano-silica particles may have a diameter of about 10 nm to about 20 nm. The release layer includes nano-silica particles having a diameter in the above range, it is possible to suppress the light scattering effect, it can give excellent transparency and gloss and excellent cutting properties. Specifically, when the diameter of the nano-silica particles exceeds the above range, the release layer may become opaque, and accordingly, the color of the colored layer is not clearly recognized, and design may be deteriorated. And, as the diameter of the nano-silica particles increases, there may be a problem that the surface roughness increases, leading to a decrease in print quality, for example, glossiness. Nano silica particles can be measured by a specific surface area meter (BET).

In addition, the nano-silica may be a colloidal silica having a chain shape. The colloidal silica may have a chain shape having a structure in which a certain number, series or partial branching of spherical colloidal silica, which is a spherical or primary particle in which ultrafine particles of silicic anhydride are dispersed in a dispersion medium, is connected in a bead shape. have.

The release layer may include a colloidal silica having a chain shape together with the acrylic resin to improve the cutting property. The release layer is not a spherical colloidal silica, but a colloidal silica having a chain shape, and may contain a small amount of silica to effectively improve cutting properties.

In addition, although spherical colloidal silica and colloidal silica having a chain shape are measured with similar particle diameters in the results of a specific surface area meter (BET), the actual particle diameter of the colloidal silica having a chain shape shows a small effect, resulting in better transparency. Can be represented.

The release layer may include about 15 parts by weight to about 30 parts by weight of the nano-silica compared to 100 parts by weight of the acrylic resin. The release layer may exhibit excellent transparency and cutability by including the nano-silica in the above range. Specifically, when the content of the nano-silica is less than the above range, transparency and cutability may deteriorate, resulting in poor print matching. In addition, when the content of the nano-silica exceeds the above range, cracks are generated in the transfer laminate in the process of manufacturing the electromagnetic wave transmission cover, and there is a problem that the transfer laminate can be easily broken.

The colored layer is laminated between the release layer and the adhesive layer, and includes pigments such as carbon black, and may exhibit printing characteristics of parts other than metal such as a front grill and/or an emblem. In addition, the colored layer can prevent the radar device from being recognized in front of the vehicle and thereby harming the aesthetics. The colored layer may include a polyurethane-based resin and a melamine resin together with the pigment. The colored layer may have a thickness of about 4 μm to about 8 μm.

The adhesive layer is attached to the transparent resin layer, and includes a base resin and nano silica, and improves print matching with excellent cutting properties along with the release layer, and can exhibit excellent adhesion. In addition, the adhesive layer exhibits excellent transparency, so that the metallic luster of the metal layer can be well recognized from the outside of the vehicle.

The base resin of the adhesive layer may include one selected from the group consisting of vinyl acetate resin, polyester resin, polyolefin resin, acrylic resin, urethane resin and combinations thereof. The adhesive layer may impart excellent adhesion to the transparent layer by including the base resin. For example, the adhesive layer has a glass transition temperature of 60 °C to 75 °C and a weight average molecular weight of 60,000 g/mol to 80,000 g/mol of a vinyl acetate-based resin, for example, a copolymer of vinyl chloride and vinyl acetate. It can contain. In addition, the adhesive layer may include polypropylene modified with polyolefin-based resin, for example, chlorinated polypropylene, glass transition temperature is 40°C to 60°C, and weight average molecular weight is 40,000g/mol to 70,000 g/mol acrylic resin, for example, a copolymer of methyl methacrylate and butyl methacrylate. The adhesive layer is a combination of two or more of the resin Including it can exhibit excellent adhesion and adhesion between the transparent resin layer and the colored layer. Accordingly, even after the hot stamping process, excellent print matching properties and design properties can be exhibited. In addition, with excellent adhesion between interfaces, it can exhibit excellent water resistance, moisture resistance, heat resistance, and salt water resistance to improve weather resistance.

The adhesive layer includes nano silica together with the base resin, and the nano silica of the adhesive layer may be the same as the nano silica of the release layer. The adhesive layer comprises the same nano-silica as the release layer, while securing the transparency, by imparting an appropriate surface free energy to improve the adhesion with the transparent resin layer, it is possible to improve the print matching with excellent cutting properties have. Accordingly, it is possible to exhibit improved design and weather resistance along with excellent radio wave transmittance.

The adhesive layer may include about 5 parts by weight to about 15 parts by weight of the nano-silica compared to 100 parts by weight of the base resin. The adhesive layer may exhibit excellent adhesion and cutting properties, including the nano-silica in the above range. Specifically, when the content of the nano-silica is less than the above range, there may be a problem that the cutting property is not expressed. And, when the content of the nano-silica exceeds the above range, the adhesion is reduced, it is possible to inhibit the stability of the transfer laminate. That is, when slitting with a certain width in the mother roll, the transfer laminate may be broken, resulting in a problem in that powder is generated in the cut section of the roll. The adhesive layer may be uniformly applied through a roll-to-roll process, and the adhesive layer may have a thickness of about 1 μm to about 2 μm.

The ratio of the weight of the nano-silica to 100 parts by weight of the base resin of the adhesive layer to the weight of the nano-silica compared to 100 parts by weight of the acrylic resin of the release layer may be about 1:2 to about 1:3. The transfer laminate laminated between the transparent resin layer and the metal layer includes a base resin and nano silica, and an adhesive layer attached to the transparent resin layer; A release layer comprising an acrylic resin and nano silica; And a colored layer laminated between the adhesive layer and the release layer; and including the weight ratio of the nano-silica contained in the adhesive layer and the release layer in the above range, it may exhibit excellent cutability and adhesion. For example, in relation to the content of the release layer nano-silica based on 100 parts by weight of the resin of each layer of the adhesive layer and the resin layer, when the weight ratio of the adhesive layer nano-silica is less than the above range, the cutting property is not expressed and burr There may be a problem that print matching is deteriorated, such as is generated, when the weight ratio of the adhesive layer nano-silica exceeds the above range, the adhesion and cutting properties are poor, the transfer of the transfer laminate is not well done, the transparent resin layer The boundary between the convex and concave parts of the can become unclear. Accordingly, print matching performance may be deteriorated and design may be deteriorated.

The electromagnetic wave transmission cover may include a metal layer on one surface of the transfer laminate. The metal layer may be a metal-like composite film. In the electromagnetic wave transmission cover, the metal layer may be manufactured to have a complicated three-dimensional structure by sputtering and depositing metal or the like on the injection material. The electromagnetic wave transmission cover can prevent metal from being oxidized by including a metal-like composite film as a metal layer, and can reduce the defect generation rate, and is economical, and the metal layer can be included in the electromagnetic wave transmission cover with a uniform thickness. Accordingly, excellent design and electromagnetic transmittance can be exhibited. In addition, the metal-like composite film may represent a metal including a resin other than a metal, thereby preventing a problem of metal oxidation.

The base layer is acrylonitrile Butadiene Styrene (ABS), acrylonitrile Styrene Acrylate (ASA), acrylonitrile ethylene propylene rubber styrene (AES) And a resin injection material selected from the group consisting of and combinations thereof.

Another embodiment of the present invention comprises the steps of laminating a transfer laminate on a carrier film; Injection molding a transparent resin layer having irregularities; Laminating a transfer laminate laminated on the carrier film on a transparent resin layer having the uneven portion, and transferring the transfer laminate by a hot stamp process; Forming a metal layer on the transfer laminate; And forming a base layer on the metal layer, wherein the transfer laminate includes a base resin and nano silica and an adhesive layer attached to the transparent resin layer; A release layer comprising an acrylic resin and nano silica; And a colored layer stacked between the adhesive layer and the release layer.

In the case of manufacturing an electromagnetic wave transmission cover having the above-described lamination structure using an in-mold process, the matching property between printing that realizes a metallic color such as a front grill and an emblem and a dark color around it is deteriorated, and the design is poor. have.

The method of manufacturing the electromagnetic wave transmission cover is a hot stamping process in which volatile substances (VOC) are not generated, rather than a general coating containing an organic solvent, and an electronic laminate is environmentally attached to the iron portion of the transparent resin layer, in addition to the metal expression portion. The shaded part can be represented, and the design can be improved with excellent print matching.

First, the method of manufacturing the electromagnetic wave transmission cover includes a step of laminating a transfer laminate on a carrier film. The carrier film may include a polyester-based film. The carrier film may have a thickness of about 12 μm to about 50 μm. Specifically, it may have a thickness of about 12 μm to about 25 μm.

A transfer laminate comprising an adhesive layer, a colored layer and a release layer is laminated on the carrier film. The contents of the transfer laminate including the adhesive layer, the colored layer, and the release layer are as described above.

Then, the step of injection molding a transparent resin layer having an uneven portion. The transparent resin layer may be manufactured by injection molding in a mold having a three-dimensional concavo-convex portion according to the shape of a front grill and/or an emblem.

And, the step of laminating the transfer laminate laminated on the carrier film on the transparent resin layer having the uneven portion, and transferring the transfer laminate by a hot stamp process. 2 is a method of manufacturing an electromagnetic wave transmission cover according to an embodiment of the present invention, the transfer laminate laminated on the carrier film is laminated on the convex portion of the transparent resin layer having irregularities, and stamped on the carrier film It is a schematic cross-sectional view showing that the member is placed and pressed, and FIG. 3 is a schematic cross-sectional view showing that the transfer laminate is transferred to the transparent resin layer after the stamp member is separated and the carrier film is removed.

Specifically, the step of transferring the transfer laminate may include the step of laminating the transfer laminate laminated on the carrier film to the convex portion of the transparent resin layer having the uneven portion. At this time, the transfer laminate laminated on the carrier film is attached to the convex portion of the transparent resin layer, not attached to the concave portion, and covers the concave portion on the extension line of the convex portion.

And, by placing a stamp member on the carrier film, and pressing the transfer laminated body laminated on the carrier film with the heated stamp member so that the transfer laminated body in close contact with the iron portion of the transparent resin layer. can do.

And, it may include the step of peeling the carrier film, the transfer layer except for the transfer laminate attached to the iron portion of the transparent resin layer with the carrier film. At this time, as described above, the transfer laminate includes the adhesive layer, the colored layer, and the release layer, and covers the transfer laminate and the recesses attached to the iron portions of the transparent resin layer. With excellent cutting performance between the transfer laminates, and excellent adhesion between the transparent resin layer and the transfer laminates, it can exhibit improved print matching and electromagnetic wave transmittance and design.

Then, forming a metal layer on the transfer laminate; And forming a base layer on the metal layer. Matters regarding the metal layer and the base layer are as described above.

(Example)

Example 1

A release layer as a transfer laminate, a colored layer, and an adhesive layer were sequentially stacked on a polyester film as a carrier film. At this time, the release layer in contact with the polyester film includes a polymethyl methacrylate having a weight average molecular weight of 40,000 g/mol, a glass transition temperature of 108°C, and a chain shape, and colloidal nano silica having an average particle diameter of 12 nm. And, 20 parts by weight of the colloidal nano-silica compared to 100 parts by weight of the polymethyl methacrylate. And, the adhesive layer comprises the same colloidal nano-silica as the base resin and release layer, including chlorinated polypropylene (CPP), polyester, polyvinyl chloride acetate and acrylic resin, and 10 parts by weight of the colloidal nano silica compared to 100 parts by weight of the total base resin.

Then, a transparent resin layer containing polycarbonate was injection molded to prepare a transparent resin layer having irregularities. Then, the transfer laminate laminated on the carrier film was laminated on the convex portion of the transparent resin layer having the concavo-convex portion. At this time, the adhesive layer of the transfer laminate was laminated so as to adhere to the iron portion of the transparent resin layer.

Then, a stamp member was placed on the carrier film, and the stamp member was removed after pressing the transfer laminate laminated on the carrier film with the heated stamp member.

Thereafter, the carrier film was peeled off, and the remaining transfer laminate covering the concave portion except the transfer laminate attached to the iron portion of the transparent resin layer was peeled together with the carrier film.

Then, a metal layer composite film is laminated on the transfer laminate to form a metal layer, and a base layer including acrylonitrile styrene acrylate (ASA) is formed on the metal layer composite film to cover the electromagnetic wave transmission. Was prepared.

Example 2

A release layer, a colored layer and an adhesive layer, which are transfer laminates, were sequentially stacked on a carrier film (polyester film). At this time, the release layer in contact with the polyester film includes a colloidal nano-silica having a weight average molecular weight of 70,000 g/mol, a polymethyl methacrylate having a glass transition temperature of 112°C, and a chain shape and an average diameter of particles of 12 nm. And, it was made to contain 20 parts by weight of the colloidal nano silica compared to 100 parts by weight of the polymethyl methacrylate. A transfer laminate laminated on a carrier film and an electromagnetic wave transmission cover including the same were prepared in the same manner as in Example 1 except for this.

Example 3

A release layer, a colored layer and an adhesive layer, which are transfer laminates, were sequentially stacked on a carrier film (polyester film). At this time, the release layer in contact with the polyester film includes a colloidal nano-silica having a weight average molecular weight of 70,000 g/mol, a polymethyl methacrylate having a glass transition temperature of 112°C, and a chain shape and an average diameter of particles of 12 nm. And, it was made to contain 30 parts by weight of the colloidal nano silica compared to 100 parts by weight of the polymethyl methacrylate. A transfer laminate laminated on a carrier film and an electromagnetic wave transmission cover including the same were prepared in the same manner as in Example 1 except for this.

Comparative Example 1

A release layer, a colored layer and an adhesive layer, which are transfer laminates, were sequentially stacked on a carrier film (polyester film). At this time, the release layer contacting the polyester film was made to include polymethyl methacrylate without the colloidal nano-silica and having a weight average molecular weight of 70,000 g/mol and a glass transition temperature of 112°C. A transfer laminate laminated on a carrier film and an electromagnetic wave transmission cover including the same were prepared in the same manner as in Example 1 except for this.

Comparative Example 2

A release layer, a colored layer and an adhesive layer, which are transfer laminates, were sequentially stacked on a carrier film (polyester film). At this time, the release layer in contact with the polyester film is a transfer laminate stacked on a carrier film in the same manner as in Example 1, except that it was formed by applying 5 g/m 2 of Wax dispersion (solid content 0.5 wt%), and An electromagnetic wave transmission cover was prepared.

Comparative Example 3

A release layer, a colored layer and an adhesive layer, which are transfer laminates, were sequentially stacked on a carrier film (polyester film). At this time, the adhesive layer without the colloidal nano-silica, chlorinated polypropylene (Chlorinated Polypropylene, CPP), polyester, polyvinyl chloride acetate (Polyvinyl Chloride Acetate) and the average diameter of the particles including the acrylic resin 1 It was made to include silica of µm. A transfer laminate laminated on a carrier film and an electromagnetic wave transmission cover including the same were prepared in the same manner as in Example 1 except for this.

evaluation

Experimental Example 1: Adhesion

The adhesion of the electromagnetic wave transmission cover of the above Examples and Comparative Examples was measured through a cross-cut adhesion test according to ASTM D3359. Specifically, the transparent resin layer surface of the electromagnetic wave transmission cover was drawn with a razor blade horizontally and vertically at 1 mm intervals to create a total of 100 square checkered eyes. Then, after attaching the adhesive tape on the transparent resin layer, when the tape was peeled off again, the number of peeled cross cuts was counted to evaluate the degree of adhesion. Specifically, the adhesion was evaluated by the following evaluation criteria, and the results are shown in Table 1 below. The smaller the number of peeled cross cuts, the better the adhesion.

(Evaluation standard)

5B: The number of peeled cross cuts is 0 to 4

4B: The number of peeled cross cuts is 5 to 14

3B: The number of peeled cross cuts is 15 to 34

2B: 35 to 64 number of peeled crosscuts

1B: When the number of peeled crosscuts is 65 or more

Experimental Example 2: Cutting property

An injection material having a concave-convex structure in which a grid with a thickness of 1 mm was engraved at 5 mm intervals in a square with a width of 3.5 cm and a height of 3.5 cm was prepared. Then, a release layer, a colored layer, and an adhesive layer, which are transfer laminates, were sequentially stacked on the carrier films prepared in Examples and Comparative Examples, and then transferred to the injection material by Roll on Stamping. Then, the release layer, the colored layer and the adhesive layer, which are transfer laminates, were transferred only to the iron portions of the injection material, and the degree of not being transferred to the grid formed by the recesses was compared to evaluate the cutability. Specifically, when the entire lattice formed by the main portion of the injection material is 100, the transfer laminate is transferred only to the iron portion of the injection material as shown in FIG. 1, and the rest is cut so that the transfer laminate is not left in the lattice formed by the main portion. Was referred to as 100% cutting property. In addition, when the transfer laminate has poor cutability and the transfer laminate remains in the grid formed by the recess, it is formed by the recess hidden by the transfer stack remaining without cutting in the total number of grids (m) formed by the recess. The number of grids (X=mn), in which the transfer stack was not left, was counted by subtracting the number of grids (n), that is, the transfer stack was cut and expressed as %.

Figure 4 shows the measurement results of the cutting properties of Examples 1 to 3, Figure 5 shows the measurement results of the cutting properties of Comparative Example 1.

Experimental Example 3: Glossiness

In the electromagnetic wave transmission cover of the above Examples and Comparative Examples, the glossiness of the portions expressed in shades other than the metal expression portion was confirmed by measuring a micro gloss meter (BYK Gardner) facing the transparent resin layer. The value measured at 60° was used as the gloss value. At 60°, when the minimum gloss is 60 or more, it can be regarded as excellent transparency, and when it is less than 60, the transparency is poor.

Adhesion Cutting property (cutting property) Glossiness Example 1 5B 100 62 Example 2 5B 100 65 Example 3 5B 100 64 Comparative Example 1 5B 60 63 Comparative Example 2 5B 50 61 Comparative Example 3 5B 100 10

As shown in Table 1, it can be seen that the Examples exhibit excellent cutting properties together with excellent adhesion, and at the same time, excellent transparency and improved design. On the other hand, in Comparative Examples 1 and 2, when the carrier film is peeled, burrs are generated a lot, and the cutting property is deteriorated, and Comparative Example 3 can be confirmed that the glossiness is significantly lowered.

As described above, the present invention has been described with reference to the exemplified drawings, but the present invention is not limited by the examples and drawings disclosed in the present specification, and can be varied by those skilled in the art within the scope of the technical idea of the present invention. It is obvious that modifications can be made. In addition, although the operation and effect according to the configuration of the present invention has not been explicitly described while explaining the embodiment of the present invention, it is natural that the effect predictable by the configuration should also be recognized.

100: electromagnetic wave transmission cover
10: transparent resin layer
11: iron
12: Main part
20: transfer laminate
21: adhesive layer
22: colored layer
23: release layer
24: carrier film
30: metal layer
40: base layer
200: no stamp

Claims (14)

It includes a transparent resin layer, a transfer laminate, a metal layer and a base layer,
The transfer laminate includes a base resin and nano silica, and an adhesive layer attached to the transparent resin layer; A release layer comprising an acrylic resin and nano silica; And a colored layer laminated between the adhesive layer and the release layer.
Electromagnetic wave transmission cover.
According to claim 1,
The transparent resin layer has an uneven portion, and includes one resin selected from the group consisting of polymethyl methacrylate (PMMA), polycarbonate, PC, and combinations thereof.
Electromagnetic wave transmission cover.
According to claim 1,
The glass transition temperature of the acrylic resin of the release layer is 100 ℃ to 115 ℃
Electromagnetic wave transmission cover.
According to claim 1,
The weight average molecular weight of the acrylic resin of the release layer is 40,000g/mol to 70,000 g/mol
Electromagnetic wave transmission cover.
According to claim 1,
The release layer contains 15 parts by weight to 30 parts by weight of the nano-silica compared to 100 parts by weight of the acrylic resin
Electromagnetic wave transmission cover.
According to claim 1,
The nano-silica contained in the adhesive layer and the release layer is the same,
The nano-silica particles have a diameter of 10 nm to 20 nm
Electromagnetic wave transmission cover.
According to claim 1,
The nano-silica comprises colloidal silica having a chain shape
Electromagnetic wave transmission cover.
According to claim 1,
The base resin of the adhesive layer comprises one selected from the group consisting of vinyl acetate resin, polyester resin, polyolefin resin, acrylic resin, urethane resin and combinations thereof.
Electromagnetic wave transmission cover.
According to claim 1,
The adhesive layer comprises 5 parts by weight to 15 parts by weight of the nano-silica compared to 100 parts by weight of the base resin
Electromagnetic wave transmission cover.
According to claim 1,
The ratio of the weight of the nano silica to 100 parts by weight of the base resin of the adhesive layer to the weight of the nano silica relative to 100 parts by weight of the acrylic resin of the release layer is 1:2 to 1:3
Electromagnetic wave transmission cover.
According to claim 1,
The transfer laminate is a transfer product attached to the iron portion of the transparent resin layer by a hot stamp process
Electromagnetic wave transmission cover.
According to claim 1,
The metal layer is a metal-like composite film
Electromagnetic wave transmission cover.
Laminating a transfer laminate on the carrier film;
Injection molding a transparent resin layer having irregularities;
Laminating a transfer laminate laminated on the carrier film on a transparent resin layer having the uneven portion, and transferring the transfer laminate by a hot stamp process;
Forming a metal layer on the transfer laminate; And
Including; forming a base layer on the metal layer;
The transfer laminate includes a base resin and nano silica, and an adhesive layer attached to the transparent resin layer; A release layer comprising an acrylic resin and nano silica; And a colored layer laminated between the adhesive layer and the release layer.
Method for manufacturing an electromagnetic wave transmission cover.
The method of claim 13,
The step of transferring the transfer laminate,
Laminating the transfer laminate laminated on the carrier film to the convex portion of the transparent resin layer having the concave-convex portion;
Placing a stamp member on the carrier film, and pressing the transfer laminate stacked on the carrier film with the heated stamp member; And
And peeling the carrier film, and peeling the remaining transfer laminate except the transfer laminate attached to the iron portion of the transparent resin layer together with the carrier film.
Method for manufacturing an electromagnetic wave transmission cover.

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