Matte-type electromagnetic interference shielding film containing bio-based components and its manufacturing method

Abstract

To provide a matte type electromagnetic interference shielding film containing a bio-based component that has characteristics such as good surface insulation, high surface hardness, good chemical resistance, high shielding, good adhesive strength, low transmission loss, high transmission quality, high bio-based content, matte appearance, good operability, high heat resistance, a long storage period of an inner layer conductive paste, and storage stability, and to provide a method for producing the same.SOLUTION: There is provided a matte type electromagnetic interference shielding film 100 containing a bio-based component that comprises: a bio-based conductive paste layer 104 having a thickness of 3 to 50 μm and containing a bio-based resin and a petrochemical resin; a metal layer 103 having a thickness of 0.1 to 15 μm; and a bio-based insulating layer 101 having a thickness of 2 to 50 μm and containing a bio-based resin and a petrochemical resin.SELECTED DRAWING: Figure 1A

Description

[Technical field]

[0001] The present disclosure relates to the technical field of shielding films having high shielding properties, and in particular to a matte-type electromagnetic interference shielding film containing a bio-based component and a method for producing the same. [Background technology]

[0002] Bio-based is an important renewable material, which has the characteristics of reusability and renewable energy, similar to solar energy, wind energy, or geothermal energy, and when used in plant growth, it helps absorb carbon dioxide and reduce the accumulation of greenhouse gases. In recent years, various bio-based material technologies have been gradually developed to replace the existing petrochemical material technologies, and in order to meet the needs for future energy conservation, carbon emission reduction, and avoiding the depletion of the earth's resources, various bio-based material products being developed are replacing the existing petrochemical material products. In addition, the requirements for the manufacturing conditions of various bio-based material products can gradually reduce human dependence on petroleum, and increase the use of renewable agricultural resources, which helps to reduce the adverse effects on the environment and health. The methods for promoting the sales status of bio-based products in the market are mainly divided into the following two parts: (1) government agencies and their contractors are compulsorily purchasing bio-based products, and (2) voluntary labeling of bio-based products by businesses, which explains the content of verified bio-based ingredients contained in the products or packaging to consumers through voluntary labeling. The testing standard for biobased content is mainly ASTM D6866( 14It is measured by one of the three methods described in the 1990 C dating method. For example, the Japan Organic Recycling Association (JORA) measures the weight percent (wt.%) of biobased and petrochemical derived components, the United States Department of Agriculture (USDA) measures the ratio of biobased carbon to petrochemical carbon according to a revised version of ASTM D6866-12, and other countries often use the ratio of biobased and petrochemical derived components in a material to determine whether the material is biobased plastic and how biobased it is.

[0003] Regarding the design of the shielding film, for example, a black polyimide film is required to meet the requirements of product appearance, surface protection, etc. In addition, commercially available polyimides are mainly manufactured by the casting method, but since the dimensional stability of thin films manufactured by the uniaxial stretching method of the casting method does not meet the industry's requirements, biaxial stretching methods are more and more required, and the requirements for equipment and manufacturing processes are higher. In addition, in order to meet the market's demand for lighter and thinner electronic products, when manufacturing multi-layer boards for flexible printed circuits (FPCs), it is necessary to reduce the thickness of the flexible printed circuit board material to meet the ultra-thin products required by users. However, when polyimide manufacturers design the thinning thickness to 5 to 7.5 μm in order to reduce the thickness of the thin film, it is difficult to meet the currently required matte surface (glossiness less than 25 GU) in terms of appearance, and the general technical indicators such as its mechanical strength, processing operability, and bendability also cannot meet the requirements of the industry standards, resulting in a low product yield.

[0004] In addition, scientific research organizations are working toward the development of bio-based polyimide resin thin films produced from recycled raw materials as bio-based raw materials. For example, organizations such as the Institute of Materials Science and Engineering at Tsinghua University, the Polymer Institute of the Department of Chemical Engineering at Tsinghua University, the Changchun Institute of Applied Chemistry at the Chinese Academy of Sciences, and Jilin University have produced a series of polyimide resins having bio-based components from recycled raw materials such as isosorbide, isomannite, and lignin derivatives (Acta Polymerica Sinica, 2006 (2): 284-288, Polymer, 2015, 74: 38-45, Acta Polymerica Sinica, 2019 (3): 261-270). However, since the recycled raw materials contain a large amount of aliphatic functional groups, polyimide thin films produced from resins derived from such raw materials generally have poor heat resistance and mechanical performance. Therefore, although there are technologies for producing polyimide resins from recycled raw materials, it is necessary to overcome the problem that the performance of the polyimide thin films produced by these technologies is insufficient.

[0005] In order to solve the above problems of applying thin polyimide films and colored thin films to shielding films, a colored polyimide film is replaced with an epoxy resin or polyurethane ink with a release film, thereby obtaining an insulating layer that is thin and has a matte surface. However, the ink-type insulating layer generally has poorer mechanical strength, insulation, hardness, chemical resistance, heat resistance, etc. than black polyimide thin film, so the development of applying polyimide varnish to release film has been further promoted. At the same time, the manufacturing process can use bio-based component design, but polyimide thin film made with bio-based polyimide resin generally has poor heat resistance and mechanical performance. Therefore, by changing the insulating layer resin, adding powder, or changing the powder content ratio and particle size, etc., an insulating layer with various advantages such as high flame retardancy, high ionic purity, high hardness, high thermal conductivity, high bio-based content, etc. can be obtained. In addition, compared with a thin film manufactured by a casting method manufacturing process, a varnish-type insulating layer has better dimensional stability because there is no residual stress from the manufacturing process. Compared with a thin film, the varnish type is more easily processed for downstream manufacturing processes because it is directly formed on a release film.

[0006] In addition, as the requirements for electromagnetic interference shielding performance increase, the thickness of the metal layer in the electromagnetic interference shielding film structure becomes increasingly thicker. However, as the metal layer becomes thicker, disadvantages also appear, particularly in the solder heat resistance of the electromagnetic interference shielding film and in simulation tests of the user's Surface Mount Technology (SMT) manufacturing process, such as large-area peeling in tin plating tests after the aging process under normal conditions, large-area peeling of the electromagnetic interference shielding film after the SMT manufacturing process, or a significant increase in on-resistance in wiring during the SMT manufacturing process. When a thick shielding metal layer and a thin insulating layer are used in combination with a conductive paste contact layer, a series of weather resistance problems are likely to occur, such as a significant increase in on-resistance and reduced adhesion in high temperature and humidity environments or thermal shock tests, and even peeling of the shielding metal layer.

[0007] As for the product types and technical problems mentioned above, CN 203194086U (Patent Document 1) discloses an ink-type electromagnetic shielding film that does not contain a metal layer, CN 203859982U (Patent Document 2) and CN 205864954U (Patent Document 3) disclose ink-type electromagnetic shielding films with metal plating, CN 107791641B (Patent Document 4), CN 206481556U (Patent Document 5), and CN 108541204B (Patent Document 6) disclose thin-film type electromagnetic shielding films with metal plating, and CN 210275019U (Patent Document 7) discloses an outer layer that is a matte undercoat layer, and uses conductive fibers instead of a metal electromagnetic shielding film. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] China Utility Model No. 203194086 [Patent Document 2] China Utility Model No. 203859982 [Patent Document 3] China Utility Model No. 205864954 [Patent Document 4] Chinese Patent No. 107791641 [Patent Document 5] China Utility Model No. 206481556 [Patent Document 6] Chinese Patent No. 108541204 [Patent Document 7] China Utility Model No. 210275019 Specification Summary of the Invention [Problem to be solved by the invention]

[0009] An object of the present disclosure is to provide a matte-type electromagnetic interference shielding film containing a bio-based component, which has properties such as good surface insulation, high surface hardness, good chemical resistance, high shielding properties, good adhesive strength, low transmission loss, high transmission quality, high bio-based content, matte appearance, good operability, high heat resistance, a long shelf life of an inner-layer conductive paste, and storage stability, and a method for producing the same. [Means for solving the problem]

[0010] Therefore, the present disclosure provides a matte-type electromagnetic interference shielding film containing a bio-based component, the film comprising a bio-based conductive paste layer having a thickness of 3 to 50 μm and containing a bio-based resin and a petrochemical resin, a metal layer having a thickness of 0.1 to 15 μm, and a bio-based insulating layer having a thickness of 2 to 50 μm and containing a bio-based resin and a petrochemical resin, the metal layer being a metal plating layer or a porous metal layer formed on the bio-based conductive paste layer, the bio-based insulating layer being formed on the metal layer and the metal layer being located between the bio-based insulating layer and the bio-based conductive paste layer, the bio-based insulating layer having a first surface and a second surface opposite to the first surface, the second surface facing the metal layer, the first surface and the second surface having different surface roughnesses Rz, the surface roughness Rz being in the range of 0.001 to 10 μm, the bio-based content of the matte-type electromagnetic interference shielding film being in accordance with the ASTM A11111 standard. The present invention provides a matte-type electromagnetic interference shielding film containing bio-based components, in which the ratio of bio-based carbon to petrochemical carbon is 20 to 100%, in accordance with D6866-12.

[0011] In one specific embodiment, the matte-type electromagnetic interference shielding film containing a bio-based component has a thickness of 2 to 50 μm, contains a bio-based resin and a petrochemical resin, and further includes a bio-based adhesive layer formed on the metal layer such that the metal layer is located between the bio-based adhesive layer and the bio-based conductive paste layer.

[0012] In one specific embodiment, the matte-type electromagnetic interference shielding film containing the bio-based component further comprises a carrier layer having a thickness of 12.5 to 250 μm, the carrier layer being formed on the first surface of the bio-based insulating layer, and after the carrier layer is peeled off, the first surface of the bio-based insulating layer has a gloss of 0 to 60 GU at a measurement angle of 60°.

[0013] In one specific embodiment, the carrier layer is a carrier film or a release film, and the material forming the carrier layer is at least one selected from the group consisting of polypropylene, polyethylene terephthalate, polyimide, polyphenylene sulfide, polyethylene naphthalate, polyurethane, and polyamide, and the polypropylene is biaxially oriented polypropylene.

[0014] In one specific embodiment, the carrier layer contains at least one inorganic powder selected from the group consisting of calcium sulfate, carbon black, silicon dioxide, titanium dioxide, zinc sulfide, zirconium oxide, calcium carbonate, silicon carbide, boron nitride, alumina, talc powder, aluminum nitride, glass powder, quartz powder, and clay, and the particle size of the inorganic powder in the carrier layer is 10 nm to 20 μm.

[0015] In one specific embodiment, the bio-based resin and the petrochemical resin in each of the bio-based insulating layer, the bio-based adhesive layer, and the bio-based conductive paste layer are each independently at least one selected from the group consisting of epoxy resin, acrylic resin, polyurethane, urethane resin, silicone rubber resin, parylene resin, bismaleimide resin, styrene-ethylene-butylene-styrene block copolymer polyimide resin, and polyamideimide. Here, the content of the bio-based resin in the bio-based insulation layer is more than 0 weight% and 100 weight% or less, and the content of the petrochemical resin is 0 to 80 weight%, relative to the total weight of the bio-based insulation layer, the content of the bio-based resin in the bio-based adhesive layer is 0 weight% to 100 weight% or less, and the content of the petrochemical resin is 0 to 80 weight%, relative to the total weight of the bio-based adhesive layer, and the content of the bio-based resin in the bio-based conductive paste layer is more than 0 weight% and 95 weight% or less, and the content of the petrochemical resin is 0 to 70 weight%, relative to the total weight of the bio-based conductive paste layer.

[0016] In one specific embodiment, at least one of the bio-based insulating layer and the bio-based adhesive layer further contains at least one inorganic powder selected from the group consisting of calcium sulfate, carbon black, silicon dioxide, titanium dioxide, zinc sulfide, zirconium oxide, calcium carbonate, silicon carbide, boron nitride, alumina, talc powder, aluminum nitride, glass powder, quartz powder, and clay, and the particle size of the inorganic powder is 10 nm to 20 μm. Here, the content of the inorganic powder in the bio-based insulating layer is more than 0 wt % and not more than 50 wt % based on the total weight of the bio-based insulating layer, and the content of the inorganic powder in the bio-based adhesive layer is more than 0 wt % and not more than 50 wt % based on the total weight of the bio-based adhesive layer.

[0017] In one specific embodiment, at least one of the bio-based insulation layer and the bio-based adhesive layer further comprises at least one flame-retardant compound selected from the group consisting of halogen, phosphorus-based, nitrogen-based and boron-based compounds, wherein the content of the flame-retardant compound in the bio-based insulation layer is 1 to 40 wt % based on the total weight of the bio-based insulation layer, and the content of the flame-retardant compound in the bio-based adhesive layer is 1 to 50 wt % based on the total weight of the bio-based adhesive layer.

[0018] In one specific embodiment, at least one of the bio-based insulating layer and the bio-based adhesive layer contains an inorganic pigment and / or an organic pigment to form a colored layer having a non-natural color, the inorganic pigment being at least one selected from the group consisting of cadmium red, cadmium lemon yellow, cadmium yellow, titanium dioxide, carbon black, black iron oxide, and black complex inorganic pigments, and the organic pigment being at least one selected from the group consisting of aniline black, perylene black, anthraquinone black, benzidine yellow pigments, phthalocyanine blue, and phthalocyanine green, the content of the inorganic pigment and / or organic pigment in the bio-based insulating layer being more than 0% by weight and not more than 50% by weight, based on the total weight of the bio-based insulating layer, and the content of the inorganic pigment and / or organic pigment in the bio-based adhesive layer being more than 0% by weight and not more than 50% by weight, based on the total weight of the bio-based adhesive layer.

[0019] In one specific embodiment, at least one of the bio-based insulating layer, the bio-based adhesive layer, and the bio-based conductive paste layer further comprises an additive, the additive being at least one selected from the group consisting of a solidifier, a catalyst, and a surfactant, wherein the content of the additive in the bio-based insulating layer is greater than 0% and less than 20% by weight based on the total weight of the bio-based insulating layer, the content of the additive in the bio-based adhesive layer is greater than 0% and less than 20% by weight based on the total weight of the bio-based adhesive layer, and the content of the additive in the bio-based conductive paste layer is greater than 0% and less than 10% by weight based on the total weight of the bio-based conductive paste layer.

[0020] In one specific embodiment, the additive is a solidifying agent, which may be selected, for example, from 4,4'-diaminodiphenylsulfone.

[0021] In one specific embodiment, the metal plating layer is a copper foil layer, a silver foil layer, an aluminum foil layer, or a nickel foil layer having a thickness of 0.1 to 5 μm. In another specific embodiment, the porous metal layer has a thickness of 2 to 15 μm and a hole diameter of 5 μm to 25 μm. The porous metal layer has a hole diameter of 5 μm to 25 μm and a porosity of 15% to 30%, and a tensile strength of 20 kg / mm 2 and the elongation rate is 5% or more.

[0022] In one specific embodiment, the bio-based conductive paste layer is a single layer bio-based conductive paste layer having a plurality of conductive particles, and the material forming the plurality of conductive particles is at least one selected from the group consisting of copper, silver, nickel, tin, gold, palladium, aluminum, chromium, titanium, zinc, carbon, nickel-gold alloy, gold-silver alloy, copper-nickel alloy, copper-silver alloy, silver-nickel alloy, and copper-nickel-gold alloy, and the content of the plurality of conductive particles is 5 to 85 wt % based on the total weight of the bio-based conductive paste layer.

[0023] In another specific embodiment, the bio-based conductive paste layer has a two-layer structure and is composed of one layer of an adhesive layer having no conductive particles and one layer of a conductive adhesive layer having a plurality of conductive particles, the adhesive layer having no conductive particles is adhered between the metal layer and the conductive adhesive layer having the plurality of conductive particles, the metal layer is a porous metal layer, and the content of the plurality of conductive particles is 5 to 85 weight % relative to the total weight of the conductive adhesive layer.

[0024] In one specific embodiment, the bio-based imide resin is a bio-based polyamideimide resin having a polyamide bond (-C(O)-N(R)-C(O)-), wherein the bio-based polyamideimide resin contains at least a constitutional unit represented by the following formula (I):

[0025] [ka] (In formula (I), n is 20 to 35.)

[0026] In one specific embodiment, the petrochemical resin is a petrochemical polyamideimide resin, which contains at least a constitutional unit represented by the following formula (II):

[0027] [ka]

[0028] In another specific embodiment, the petrochemical resin is selected from bisphenol A epoxy resin, acrylic resin, or a combination of bisphenol A epoxy resin and acrylic resin mixed in a 1:1 weight ratio.

[0029] The present disclosure provides a method for producing a bio-based insulating layer by forming the bio-based insulating layer on a carrier layer, and then solidifying the bio-based insulating layer at a temperature of 50° C. to 180° C. forming a metal plating layer on the bio-based insulating layer by one method selected from vacuum sputtering, vapor deposition, chemical plating, and electroplating; forming a bio-based conductive paste layer on the metal plating layer such that the metal plating layer is positioned between the bio-based insulating layer and the bio-based conductive paste layer; and pressing a release layer against the bio-based conductive paste layer.

[0030] In one specific embodiment, the method for producing the matte-type electromagnetic interference shielding film containing the bio-based component further includes the steps of forming another bio-based insulating layer on the bio-based insulating layer before forming the metal plating layer, solidifying the other bio-based insulating layer under conditions of 50°C to 180°C, and further forming the metal plating layer, and positioning the metal plating layer between the other bio-based insulating layer and the bio-based conductive paste layer.

[0031] In one specific embodiment, the method for producing the matte-type electromagnetic interference shielding film containing the bio-based component further includes the steps of forming a bio-based adhesive layer on the bio-based insulating layer or the other bio-based insulating layer by a coating method or a transfer method before forming the metal plating layer, and then forming the metal plating layer to position the metal plating layer between the bio-based adhesive layer and the bio-based conductive paste layer.

[0032] In one specific embodiment, the bio-based insulating layer has a hardness of 2H to 6H.

[0033] The present disclosure provides a method for producing a bio-based insulating layer by forming the bio-based insulating layer on a carrier layer, and then solidifying the bio-based insulating layer at a temperature of 50° C. to 180° C. forming a bio-based adhesive layer on the porous metal layer by coating or transfer; pressing the bio-based insulating layer against the bio-based adhesive layer so that the bio-based adhesive layer is positioned between the bio-based insulating layer and the porous metal layer; forming a bio-based conductive paste layer on the porous metal layer; and pressing a release layer onto the bio-based conductive paste layer.

[0034] In one specific embodiment, the method for producing the matte-type electromagnetic interference shielding film containing the bio-based component further includes a step of forming another bio-based insulating layer on the bio-based insulating layer after solidifying the bio-based insulating layer, and solidifying the other bio-based insulating layer under conditions of 50°C to 180°C.

[0035] In one specific embodiment, the method for producing the porous metal layer comprises the steps of: applying an aluminum layer to the thin film; A step of subjecting the surface of the aluminum layer to a peeling treatment; forming a metal layer on the surface of the peeled aluminum layer by one method selected from sputtering, vapor deposition, and plating; microetching the metal layer to form a plurality of holes; and peeling off the thin film and the aluminum layer to form a porous metal layer on the metal layer.

[0036] In one specific embodiment, the thin film is a polyimide thin film or an ethylene terephthalate thin film.The metal layer is at least one selected from the group consisting of copper, aluminum, lead, nickel, cobalt, tin, silver, iron and gold. Effect of the Invention

[0037] The advantageous effects of the present disclosure include at least the following:

[0038] 1. The surface hardness of most commercially available black ink layers and polyimide varnish layers is HB~2H, which makes the surface brittle and easily scratched, affecting the appearance and mechanical performance. However, in the bio-based insulating layer of the present disclosure, after adding powder, it helps to improve its hardness, and the hardness reaches 2H~6H. At the same time, the more the different proportions of powder increase, the different its flame retardant performance will be. The higher the proportion of mixed powder of one or more inorganic powders such as titanium dioxide, silicon dioxide, aluminum oxide, aluminum hydroxide, calcium carbonate, etc., the higher its flame retardancy will be. When higher hardness is required, it is preferable to use a mixture of one or more of titanium dioxide, (sintered) silicon dioxide, etc. When higher flame retardancy is required, it is preferable to use a mixture of one or more of aluminum hydroxide, aluminum oxide, calcium carbonate, and one or more compounds having flame retardancy such as halogen, phosphorus, nitrogen, or boron.

[0039] 2. Existing shielding films adopt thick metal layers, which are prone to problems such as large-area peeling, increased on-resistance, reduced adhesion, and peeling of the metal layer in the solder heat resistance and SMT manufacturing process tests. However, the electromagnetic interference shielding film of the present disclosure may include a thick metal plating layer having a thickness of more than 0.2 μm, even more than 0.5 μm, and may be formed by adding coarse powder to the bio-based insulating layer (or, for example, to the second insulating layer in a two-layer insulating layer, or to the insulating layer facing the metal plating layer in a multiple insulating layer). This changes the surface roughness (Rz roughening is 3 to 6 μm) and hardness (2 to 6H) between the contact surface of the bio-based insulating layer and the metal plating layer, and further forms defects when metal plating is applied (e.g., copper plating) or forms cracks when pressed, for example, generating escape holes and cracks. Alternatively, the electromagnetic interference shielding film of the present disclosure may include a porous metal layer having a function similar to the formation of escape holes, thereby significantly improving the solder heat resistance of the entire shielding film, which is useful for the subsequent manufacturing process of reflow soldering of the product.

[0040] 3. Existing shielding films use a normal metal plating layer, but the electromagnetic interference shielding film of the present disclosure may include a porous metal layer, which has good electromagnetic interference shielding performance and the property of enduring SMT. Specifically, the porous metal layer has a reflecting effect on electromagnetic waves, reflecting most of the radio frequency and microwave energy, and has a very small amount of transmission, so it has good shielding performance (more than 60 dB at 1 GHz) and can effectively shield interference caused by electromagnetic wave radiation. In addition, compared with a normal metal plating layer, the porous metal layer significantly improves the solder heat resistance of the manufactured product, and the solder heat resistance can be more than 300°C due to the downstream soldering manufacturing process.

[0041] 4. The bio-based insulating layer of the present disclosure may contain a polyimide resin, and has better surface insulating properties (e.g., insulation resistance value is greater than 1012 Ω), better impedance control ability, chemical resistance, solder resistance, and high surface hardness compared to epoxy resin (Epoxy) or polyurethane resin (PU) ink insulating layers. Compared to ultra-thin black polyimide thin films with a thickness of 5 to 7.5 μm, the present disclosure does not require a separate carrier film in the manufacturing process, making the process simpler and less costly, and commercially available thin films of this thickness often do not reach a gloss value of less than 60 GU.

[0042] 5. The disclosed matte-type electromagnetic interference shielding film containing bio-based components has a compositional design of the bio-based insulating layer and the bio-based conductive paste. The overall bio-based content is greater than 20% as measured by JORA certification and USDA certification, so it can obtain bio-based plastic certification in various countries. [Brief description of the drawings]

[0043] Hereinafter, an embodiment of the present disclosure will be described with reference to exemplary reference figures.

[0044] [Figure 1A]FIG. 1A is a schematic diagram of the structure of one embodiment of a matte-type electromagnetic interference shielding film containing a bio-based component according to the present disclosure.

[0045] [Figure 1B] FIG. 1B is a structural schematic diagram of one embodiment of a matte-type electromagnetic interference shielding film containing a bio-based component of the present disclosure, further comprising a carrier layer.

[0046] [Figure 1C] FIG. 1C is a schematic diagram of the structure of one embodiment of a matte-type electromagnetic interference shielding film containing a bio-based component of the present disclosure, further comprising a release layer.

[0047] [Figure 1D] FIG. 1D is a structural schematic diagram of another embodiment of the matte-type electromagnetic interference shielding film containing the bio-based component of the present disclosure.

[0048] [Figure 1E] FIG. 1E is a structural schematic diagram of another embodiment of the matte-type electromagnetic interference shielding film containing bio-based components of the present disclosure, further comprising a carrier layer.

[0049] [Figure 1F] FIG. 1F is a structural schematic diagram of another embodiment of the matte-type electromagnetic interference shielding film containing bio-based components of the present disclosure, further comprising a release layer.

[0050] [Diagram 2] FIG. 2 is a structural schematic diagram of another embodiment of the matte-type electromagnetic interference shielding film containing the bio-based component of the present disclosure, in which the bio-based insulating layer includes two or more insulating layers.

[0051] [Diagram 3] FIG. 3 is a structural schematic diagram of another embodiment of a matte-type electromagnetic interference shielding film including a bio-based component of the present disclosure, in which the metal layer includes one or more defects. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0052] The following describes the embodiments of the present disclosure through specific examples, and those skilled in the art can easily understand the advantages and effects of the present disclosure from the description in this specification.

[0053] However, the structures, proportions, dimensions, etc. shown in the drawings attached to this specification are intended to allow those skilled in the art to understand and view them in accordance with the contents of the specification, and are not intended to limit the limiting conditions of the implementation of this disclosure, and therefore have no substantial technical meaning. Any modification of the structure, change in proportionality, or adjustment of dimensions is included in the scope that can be covered by the technical content disclosed in this disclosure, as long as it does not affect the effects and achievable purpose of this disclosure. In addition, terms such as "one," "lower," or "upper" described in this specification are intended to make the explanation easy to understand, and do not limit the implementation scope of this disclosure, and changes or adjustments of their relative relationships are considered to be within the implementation scope of this disclosure as long as they do not substantially change the technical content. It should be noted that all numerical ranges and values ​​described in this specification are inclusive and combinable. Any numerical values ​​or endpoints, such as any integers, included in the ranges described in this specification can be used as minimum or maximum values ​​to derive further ranges. "Including," "containing," or "having" a composition or step described in this specification may further include other compositions or other steps, unless otherwise specified, and does not exclude these other compositions or other steps. Additionally, unless otherwise stated in this disclosure, the singular forms "a," "an," and "said" as used herein include plural specifics, and "or" and "and / or" as used herein are used interchangeably. It should be noted that the use of terms such as "first," "second," or "third" to describe structures in the present specification and claims is used as abbreviations of those steps / structures and is not intended to imply performing / forming those steps / structures in that order.

[0054] As shown in FIG. 1A , the matte-type electromagnetic interference shielding film 100 containing a bio-based component according to the present disclosure includes a bio-based conductive paste layer 104 having a thickness of 3 to 50 μm and containing a bio-based resin and a petrochemical resin, a metal layer 103 having a thickness of 0.1 to 15 μm and formed on the bio-based conductive paste layer 104, and a metal layer 103 having a thickness of 2 to 50 μm and containing a bio-based resin and a petrochemical resin, which is formed on the metal layer 103 so that the metal layer 103 is in contact with the bio-based insulating layer 102. A matte-type electromagnetic interference shielding film containing a bio-based component, comprising a bio-based insulating layer 101 located between the metal layer 103 and the bio-based conductive paste layer 104, the bio-based insulating layer 101 having a first surface 1011 and a second surface 1012 opposite to the first surface 1011, the second surface 1012 facing the metal layer 103, and the first surface 1011 and the second surface 1012 having different surface roughnesses Rz.

[0055] As shown in FIG. 1B, the matte-type electromagnetic interference shielding film 100 containing a bio-based component of the present disclosure further includes a carrier layer 105 having a thickness of 12.5 to 250 μm, the carrier layer 105 being formed on the first surface 1011 of the bio-based insulating layer 101, and after the carrier layer 105 is peeled off, the contact surface between the first surface 1011 of the bio-based insulating layer 101 and the carrier layer 105 has a gloss of 0 to 60 GU at a measurement angle of 60°, for example, 0, 1, 2, 3, 4, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55 or 60 GU, and preferably has a gloss of 0 to 25 GU.

[0056] As shown in FIG. 1C, the matte-type electromagnetic interference shielding film 100 containing a bio-based component of the present disclosure further includes a release layer 106 for protecting the bio-based conductive paste layer 104, and the release layer 106 is formed on the bio-based conductive paste layer 104 so that the bio-based conductive paste layer 104 is located between the metal layer 103 and the release layer 106, where the release layer is a release film having a thickness of 25 to 100 μm, a PE coated paper having a thickness of 25 to 130 μm, or a carrier film having a thickness of 25 to 100 μm, and is at least one selected from the group consisting of a PET fluorine release film, a PET silicone oil-containing release film, a PET matte release film, and a PE release film.

[0057] As shown in Figures 1D to 1F, the matte-type electromagnetic interference shielding film 100 containing a bio-based component of the present disclosure further includes a bio-based adhesive layer 102 having a thickness of 2 to 50 μm and containing a bio-based resin and a petrochemical resin, and the bio-based adhesive layer 102 is formed on the metal layer 103, and the metal layer 103 is located between the bio-based adhesive layer 102 and the bio-based conductive paste layer 104.

[0058] As shown in Fig. 2, the design of the bio-based insulating layer in the matte type electromagnetic interference shielding film 200 containing bio-based components of the present disclosure may include another form of the bio-based insulating layer 201 formed from two or more insulating layers 2013 in addition to the form of the one bio-based insulating layer 101 described above, where these insulating layers 2013 may each independently contain different components, at least one of these insulating layers 2013 contains bio-based components, and the total thickness of the formed bio-based insulating layer 201 is 2 to 50 μm. Referring to Fig. 2, the matte type electromagnetic interference shielding film 200 containing bio-based components of the present disclosure includes a release layer 206, a bio-based conductive paste layer 204, a metal layer 203, a bio-based insulating layer 201, and a carrier layer 205, but does not include a bio-based adhesive layer 102 between the metal layer 203 and the bio-based insulating layer 201. Also, in the embodiment of the insulation layer having multiple layers, the matte-type electromagnetic interference shielding film containing bio-based components of the present disclosure may not include the carrier layer 205 and / or the release layer 206 (not shown). Furthermore, the bio-based insulation layer 201 also has a first surface 2011 and a second surface 2012 opposite to the first surface 2011, the second surface 2012 facing the metal layer 203, and the first surface 2011 and the second surface 2012 have different surface roughnesses Rz.

[0059] In one specific embodiment, the surface roughness Rz of the first surface 1011 / 2011 and the second surface 1012 / 2012 of the bio-based insulating layer is each independently in the range of 0.001 to 10 μm, for example, 0.001, 0.005, 0.01, 0.05, 0.1, 0.5, 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 μm, and of these, a surface roughness Rz of 3 to 6 μm is preferred because it helps to form defects during copper plating, cracks when pressed, or defects in the porous metal layer.

[0060] As shown in Fig. 3, the matte type electromagnetic interference shielding film 300 containing bio-based components of the present disclosure includes a release layer 306, a bio-based conductive paste layer 304, a metal layer 303, a bio-based insulating layer 301, and a carrier layer 305, and the metal layer 303 is a metal plating layer or a porous metal layer. In this specific embodiment, the metal layer 303 has a larger thickness and includes one or more defects 3031, such as, but not limited to, surface dents, surface protrusions, surface cracks, cracks, breaks, bubbles, or escape holes. In an embodiment having multiple layers of insulating layers, the matte type electromagnetic interference shielding film 300 containing bio-based components of the present disclosure may not include the carrier layer 305 and / or the release layer 306 (not shown).

[0061] In one specific embodiment, the bio-based content of the matte-type electromagnetic interference shielding film is, in accordance with standard ASTM D6866-12, 20 to 100% as a ratio of bio-based carbon to petroleum-based carbon, for example, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, or 100%.

[0062] In one specific embodiment, the carrier layer is a carrier film or a release film, and the material forming the carrier layer is at least one selected from the group consisting of polypropylene, polyethylene terephthalate, polyimide, polyphenylene sulfide, polyethylene naphthalate, polyurethane and polyamide.In this specific embodiment, the polypropylene is biaxially oriented polypropylene.

[0063] In one specific embodiment, in order to have a non-natural color, the carrier layer contains at least one inorganic powder selected from the group consisting of calcium sulfate, carbon black, silicon dioxide, titanium dioxide, zinc sulfide, zirconium oxide, calcium carbonate, silicon carbide, boron nitride, alumina, talc powder, aluminum nitride, glass powder, quartz powder, and clay, and the particle size of the inorganic powder in the carrier layer is 10 nm to 20 μm, for example, 10 nm, 20 nm, 30 nm, 40 nm, 50 nm, 100 nm, 200 nm, 300 nm, 400 nm, 500 nm, 600 nm, 700 nm, 800 nm, 900 nm, 1 μm, 2 μm, 3 μm, 4 μm, 5 μm, 6 μm, 7 μm, 8 μm, 9 μm, 10 μm, 11 μm, 12 μm, 13 μm, 14 μm, 15 μm, 16 μm, 17 μm, 18 μm, 19 μm, or 20 μm.

[0064] In one specific embodiment, the bio-based resin and the petrochemical resin in the bio-based insulating layer, the bio-based adhesive layer and the bio-based conductive paste layer, respectively, are each independently at least one selected from the group consisting of epoxy resin, acrylic resin, polyurethane, urethane resin, silicone rubber resin, parylene resin, bismaleimide resin, styrene-ethylene-butylene-styrene block copolymer, polyimide resin and polyamideimide, with polyimide resin being preferred. In this specific embodiment, the content of the bio-based resin in the bio-based insulation layer is greater than 0 weight% and less than or equal to 100 weight%, for example, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, or 100 weight%, relative to the total weight of the bio-based insulation layer, and the content of the petrochemical resin is 0 to 80 weight%, for example, 0, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, or 80 weight%. Relative to the total weight of the bio-based adhesive, the content of the bio-based resin in the bio-based adhesive layer is more than 0 wt% and 100 wt% or less, for example, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, or 100 wt%, and the content of the petrochemical resin is 0 to 80 wt%, for example, 0, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, or 80 wt%. Relative to the total weight of the bio-based conductive paste layer, the content of the bio-based resin in the bio-based conductive paste layer is more than 0 weight% and not more than 95 weight%, for example, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90 or 95 weight%, and the content of the petrochemical resin is 0 to 70 weight%, for example, 0, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, or 70 weight%.

[0065] In one specific embodiment, the "polyimide-based resin" in the bio-based insulating layer refers to a polyimide resin having an imide bond skeleton, also called polyimide varnish. For example, the polyimide resin is at least one selected from the group consisting of polyimide (Polyimide, PI), polyamideimide, and polyimide (Polyimide-ester), but is not limited thereto.

[0066] In one specific embodiment, at least one of the bio-based insulating layer and the bio-based adhesive layer further comprises at least one inorganic powder selected from the group consisting of calcium sulfate, carbon black, silicon dioxide, titanium dioxide, zinc sulfide, zirconium oxide, calcium carbonate, silicon carbide, boron nitride, alumina, talc powder, aluminum nitride, glass powder, quartz powder, and clay, and the bio-based insulating layer and / or the bio-based adhesive layer further comprises at least one inorganic powder selected from the group consisting of calcium sulfate, carbon black, silicon dioxide, titanium dioxide, zinc sulfide, zirconium oxide, calcium carbonate, silicon carbide, boron nitride, alumina, talc powder, aluminum nitride, glass powder, quartz powder, and clay, In order to roughen the layer, the particle size of the inorganic powder is 10 nm to 20 μm, for example, 10 nm, 20 nm, 30 nm, 40 nm, 50 nm, 100 nm, 200 nm, 300 nm, 400 nm, 500 nm, 600 nm, 700 nm, 800 nm, 900 nm, 1 μm, 2 μm, 3 μm, 4 μm, 5 μm, 6 μm, 7 μm, 8 μm, 9 μm, 10 μm, 11 μm, 12 μm, 13 μm, 14 μm, 15 μm, 16 μm, 17 μm, 18 μm, 19 μm, or 20 μm. In this specific embodiment, the content of inorganic powder in the bio-based insulation layer is more than 0% by weight and less than 50% by weight, and the content of inorganic powder in the bio-based adhesive layer is more than 0% by weight and less than 50% by weight, and the inorganic powder content in the bio-based insulation layer and the inorganic powder content in the bio-based adhesive layer can be, for example, 1, 2, 3, 4, 5, 10, 15, 20, 25, 30, 35, 40, 45, or 50% by weight, and among them, the addition ratio is preferably more than 0% by weight and less than 20% by weight. In addition, the silicon dioxide of the present disclosure can be sintered silicon dioxide. For example, the total weight of sintered silicon dioxide, carbon black, talc powder, calcium carbonate, glass powder, and quartz powder is more than 0% by weight and less than 50% by weight, preferably more than 0% by weight and less than 20% by weight, based on the total weight of the bio-based insulation layer, but is not limited thereto. Also, by way of example, the total weight of sintered silicon dioxide, carbon black, talc powder, calcium carbonate, glass powder and quartz powder is greater than 0% by weight and less than 50% by weight, preferably greater than 0% by weight and less than 20% by weight, relative to the total weight of the bio-based adhesive layer, but is not limited thereto.

[0067] In one specific embodiment, at least one of the bio-based insulating layer and the bio-based adhesive layer further comprises at least one flame-retardant compound selected from the group consisting of halogen, phosphorus-based, nitrogen-based and boron-based compounds. In this specific embodiment, the content of the flame-retardant compound in the bio-based insulating layer is 1 to 40% by weight, for example, 1, 2, 3, 4, 5, 10, 15, 20, 25, 30, 35, or 40% by weight, based on the total weight of the bio-based insulating layer, and the addition ratio is preferably 5 to 35% by weight. In this specific embodiment, the content of the flame-retardant compound is 1 to 50% by weight, for example, 1, 2, 3, 4, 5, 10, 15, 20, 25, 30, 35, 40, 45, or 50% by weight, based on the total weight of the bio-based adhesive layer, and the addition ratio is preferably 5 to 35% by weight.

[0068] In one specific embodiment, at least one of the bio-based insulating layer and the bio-based adhesive layer may further comprise an organic powder. In another specific embodiment, the bio-based adhesive layer may further comprise polytetrafluoroethylene or a fluorine-based resin.

[0069] In one specific embodiment, at least one of the bio-based insulating layer and the bio-based adhesive layer contains inorganic and / or organic pigments to form a colored layer with a non-natural color. In this specific embodiment, the inorganic pigment is at least one selected from the group consisting of cadmium red, cadmium lemon yellow, cadmium yellow, titanium dioxide, carbon black, black iron oxide, and black complex inorganic pigments, and the organic pigment is at least one selected from the group consisting of aniline black, perylene black, anthraquinone black, benzidine yellow pigments, phthalocyanine blue, and phthalocyanine green. In this specific embodiment, the content of the inorganic and / or organic pigment in the bio-based insulating layer is more than 0% by weight and not more than 50% by weight, for example, 0, 1, 2, 3, 4, 5, 10, 15, 20, 25, 30, 35, 40, 45, or 50% by weight, based on the total weight of the bio-based insulating layer. In this specific embodiment, the content of the inorganic and / or organic pigments in the bio-based adhesive layer is greater than 0% by weight and less than or equal to 50% by weight, based on the total weight of the bio-based adhesive layer, for example 0, 1, 2, 3, 4, 5, 10, 15, 20, 25, 30, 35, 40, 45, or 50% by weight.

[0070] In one specific embodiment, at least one of the bio-based insulating layer, the bio-based adhesive layer and the bio-based conductive paste layer further comprises an additive, the additive being at least one selected from the group consisting of a solidifier, a catalyst and a surfactant, wherein the content of the additive in the bio-based insulating layer is greater than 0% by weight and less than 20% by weight, for example, 1, 2, 3, 4, 5, 10, 15 or 20% by weight, based on the total weight of the bio-based insulating layer; the content of the additive in the bio-based adhesive layer is greater than 0% by weight and less than 20% by weight, for example, 1, 2, 3, 4, 5, 10, 15 or 20% by weight, based on the total weight of the bio-based adhesive layer; and the content of the additive in the bio-based conductive paste layer is greater than 0% by weight and less than 10% by weight, for example, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10% by weight, based on the total weight of the bio-based conductive paste layer.

[0071] In one specific embodiment, the bio-based insulating layer has a hardness of 2H to 6H.

[0072] In one specific embodiment, the bio-based resin is a bio-based polyamideimide resin having imide bonds (-C(O)-N(R)-C(O)-), wherein the bio-based polyamideimide resin comprises at least a constitutional unit represented by the following formula (I):

[0073] [ka] (In formula (I), n is 20 to 35.)

[0074] In one specific embodiment, the petrochemical resin is a petrochemical polyamideimide resin, wherein the petrochemical polyamideimide resin contains at least a constitutional unit represented by the following formula (II):

[0075] [ka]

[0076] In another specific embodiment, the petrochemical resin is selected from bisphenol A epoxy resin, acrylic resin, or a combination of bisphenol A epoxy resin and acrylic resin mixed in a 1:1 weight ratio.

[0077] In one particular embodiment, the additive is a solidifying agent, for example, the additive is selected from 4,4'-diaminodiphenyl sulfone.

[0078] In one specific embodiment, the metal plating layer is a copper foil layer, a silver foil layer, an aluminum foil layer, or a nickel foil layer having a thickness of 0.1 to 5 μm. In this specific embodiment, the thickness of the metal plating is, for example, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1, 1.5, 2, 2.5, 3, 3.5, 4, 4.5, or 5 μm.

[0079] In another specific embodiment, the porous metal layer has a thickness of 2 to 15 μm, a hole diameter of 5 μm to 25 μm, and a porosity of 15% to 30%, and its tensile strength is 20 kg / mm2 or more and elongation percentage is 5% or more. In this specific embodiment, the thickness of the porous metal layer is, for example, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, or 15 μm, the hole size of the porous metal layer is, for example, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, or 25 μm, and the porosity of the porous metal layer is, for example, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 17, 28, 29, or 30%.

[0080] In one specific embodiment, the bio-based conductive paste layer is a single layer bio-based conductive paste layer having a plurality of conductive particles. In this specific embodiment, the material forming the plurality of conductive particles is at least one selected from the group consisting of copper, silver, nickel, tin, gold, palladium, aluminum, chromium, titanium, zinc, carbon, and alloys thereof. In one preferred embodiment, the alloy is at least one selected from the group consisting of nickel-gold alloy, gold-silver alloy, copper-nickel alloy, copper-silver alloy, silver-nickel alloy, and copper-nickel-gold alloy. In this specific embodiment, the content of the plurality of conductive particles is 5 to 85 wt % based on the total weight of the bio-based conductive paste layer, for example, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, or 85 wt %.

[0081] In another specific embodiment, the bio-based conductive paste layer has a two-layer structure, and is composed of one adhesive layer without conductive particles and one conductive adhesive layer with a plurality of conductive particles, where the adhesive layer without conductive particles is adhered between the metal layer and the conductive adhesive layer with a plurality of conductive particles, and the metal layer is a porous metal layer. In this specific embodiment, the content of the plurality of conductive particles is 5 to 85 wt % based on the total weight of the conductive adhesive layer, for example, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, or 85 wt %.

[0082] In one specific embodiment, the thickness of the bio-based insulating layer is 2 to 50 μm, the thickness of the bio-based adhesive layer is 2 to 50 μm, for example, 2, 3, 4, 5, 6, 7, 8, 9, 10, 15, 20, 25, 30, 35, 40, 45, or 50 μm, the thickness of the metal plating layer is 0.1 to 5 μm, for example, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1, 1.5, 2, 2.5, 3, 3.5, 4, 4.5, or 5 μm, and the thickness of the bio-based conductive paste layer is 3 to 50 μm, for example, 3, 4, 5, 6, 7, 8, 9, 10, 15, 20, 25, 30, 35, 40, 45, or 50 μm.

[0083] In another specific embodiment, the thickness of the bio-based insulating layer is 2 to 50 μm, the thickness of the bio-based adhesive layer is 2 to 50 μm, for example, 2, 3, 4, 5, 6, 7, 8, 9, 10, 15, 20, 25, 30, 35, 40, 45, or 50 μm, the thickness of the porous metal layer is 2 to 15 μm, for example, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, or 15 μm, and the thickness of the bio-based conductive paste layer is 3 to 50 μm, for example, 3, 4, 5, 6, 7, 8, 9, 10, 15, 20, 25, 30, 35, 40, 45, or 50 μm.

[0084] In another specific embodiment, the thickness of the bio-based insulating layer is 3 to 10 μm, the thickness of the bio-based adhesive layer is 3 to 10 μm, for example, 3, 4, 5, 6, 7, 8, 9, or 10 μm, the thickness of the porous metal layer is 3 to 8 μm, for example, 3, 4, 5, 6, 7, or 8 μm, and the thickness of the bio-based conductive paste layer is 5 to 15 μm, for example, 5, 6, 7, 8, 9, 10, 15, 20, 25, 30, 35, 40, 45, or 50 μm.

[0085] In a specific embodiment, the carrier layer is a carrier membrane or release film having a thickness of 12.5 to 250 μm, for example, 12.5, 13, 14, 15, 20, 40, 60, 80, 100, 120, 140, 160, 180, 200, 220, 240, 245, or 250 μm.

[0086] In one specific embodiment, the matte-type electromagnetic interference shielding film containing a bio-based component further includes a release layer, the release layer being formed on the bio-based conductive paste layer such that the bio-based conductive paste layer is located between the metal layer and the release layer. In one embodiment, the release layer is a release film having a thickness of 25 to 100 μm, for example, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, or 100 μm, and the release film is at least one selected from the group consisting of a PET fluorine release film, a PET release film containing silicone oil, a PET matte release film, and a PE release film. In another embodiment, the release layer is a PE coated paper having a thickness of 25-130 μm, for example, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100, 110, 120, or 130 μm. In another embodiment, the release layer is a carrier film having a thickness of 25-100 μm, for example, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, or 100 μm, and the carrier film is a weak adhesion carrier film.

[0087] In one specific embodiment, the method for producing a matte-type electromagnetic interference shielding film containing a bio-based component is used to produce a shielding film having a metal plating layer, A step S101 of forming a bio-based insulating layer on a carrier layer and then solidifying the bio-based insulating layer under a condition of 50°C to 180°C; Step S102 of forming a metal plating layer on the bio-based insulating layer by one selected from vacuum sputtering, deposition, chemical plating and electroplating; Step S103: forming a bio-based conductive paste layer on the metal plating layer, and positioning the metal plating layer between the bio-based insulating layer and the bio-based conductive paste layer; and pressing a release layer against the bio-based conductive paste layer (S104). In this specific embodiment, the manufacturing method includes a step S1011 of forming another bio-based insulating layer on the bio-based insulating layer before forming the bio-based metal plating layer, solidifying the other bio-based insulating layer under a condition of 50°C to 180°C, and further forming the bio-based metal plating layer, and positioning the metal plating layer between the other bio-based insulating layer and the bio-based conductive paste layer. Before forming the metal plating layer, the method may further include a step S1012 of forming a bio-based adhesive layer on the bio-based insulating layer or the other bio-based insulating layer by a coating method or a transfer method, and then forming the metal plating layer, and positioning the metal plating layer between the bio-based adhesive layer and the bio-based conductive paste layer.

[0088] In another specific embodiment, the present disclosure provides a method for producing a matte-type electromagnetic interference shielding film comprising a bio-based component for use in producing a shielding film having a porous metal layer, the method comprising: A step S201 of forming a bio-based insulating layer on a carrier layer and then solidifying the bio-based insulating layer under a condition of 50°C to 180°C; Step S202 of forming a bio-based adhesive layer on the porous metal layer by coating or transfer method; Step S203: pressing the bio-based insulating layer against the bio-based adhesive layer to position the bio-based adhesive layer between the bio-based insulating layer and the porous metal layer; forming a bio-based conductive paste layer on the porous metal layer (S204); The present invention further provides a method for producing a matte-type electromagnetic interference shielding film containing a bio-based component, the method comprising: pressing a release layer against the bio-based conductive paste layer (S205).

[0089] In this specific embodiment, the manufacturing method may further include a step S2011 of forming another bio-based insulating layer on the bio-based insulating layer after solidifying the bio-based insulating layer, and solidifying the other bio-based insulating layer under conditions of 50°C to 180°C.

[0090] Further, in this specific embodiment, the method for producing the porous metal layer comprises the steps of: a step S2012 of applying an aluminum layer to the thin film; a step S2013 of subjecting the surface of the aluminum layer to a peeling treatment; A step S2014 of forming a metal layer on the surface of the peeled aluminum layer by one method selected from sputtering, vapor deposition, and plating; S2015 microetching the metal layer to cause metal particles in the metal layer to be aligned neatly to form a plurality of holes; and a step S2016 of peeling off the thin film and the aluminum layer to form a porous metal layer on the metal layer.

[0091] In this specific embodiment, the thin film is a polyimide thin film or an ethylene terephthalate thin film, and the metal particles in the metal layer are at least one selected from the group consisting of copper, aluminum, lead, nickel, cobalt, tin, silver, iron and gold. EXAMPLES

[0092] The performance of the matte-type electromagnetic interference shielding film containing the bio-based component of the present disclosure will be described below with reference to examples and comparative examples. The concepts described in the present disclosure will be further explained in the following examples, but the examples are not intended to limit the scope of the present disclosure as described in the claims.

[0093] Examples A1 to A9 and B1 to B8 are matte-type electromagnetic interference shielding films containing the bio-based component of the present disclosure.

[0094] The materials and components used in the examples of the present disclosure are shown in Table 1 below.

[0095] [Table 1]

[0096] In the above table, R-1, R-2, R-3, R-4 and DDS are respectively as shown below.

[0097] (1) Bio-based resin R-1 A polyamideimide varnish is used. Specifically, a bio-based resin having an imide bond (-C(O)-N(R)-C(O)-) is formed by carrying out a synthesis reaction using a bio-based dianhydride and a bio-based diamine portion extracted from natural plants and animals as precursor monomers and adding cyclohexanone as a solvent. The bio-based polyamideimide resin contains at least a constitutional unit represented by the following formula (I), where n is 20 to 35.

[0098] [ka]

[0099] (2) Petrochemical resin R-2 A polyamide-imide resin, which is a petrochemical product, is used. Specifically, it is a petrochemical resin formed by a synthetic reaction of a precursor monomer extracted from a petrochemical product. The petrochemical polyamide-imide resin contains at least a constitutional unit represented by the following formula (II).

[0100] [ka]

[0101] (3) Petrochemical resin R-3: Bisphenol A epoxy resin BE501A80 (purchased from Chang Chun Chemical) is used. (4) Petrochemical resin R-4: Bisphenol A epoxy resin BE501A80 (purchased from Chang Chun Chemical) and acrylic resin JT-A1767 (purchased from JPT CORPORATION) are mixed in a weight ratio of 1:1 and used. (5) Additive DDS: 4,4'-diaminodiphenyl sulfone is used as a solidifying agent.

[0102] The thickness of each layer of the shielding film in the examples and comparative examples of the present disclosure is shown in Table 2 below.

[0103] [Table 2]

[0104] The shielding film in the embodiment of the present disclosure is manufactured as follows.

[0105] <Examples A1 and A2> According to the content of each layer component of Examples A1 and A2 in Table 1 and the thickness of each layer of Examples A1 and A2 in Table 2, a matte-type electromagnetic interference shielding film containing bio-based components is prepared, which includes a bio-based insulating layer (including two bio-based insulating layers), a bio-based adhesive layer, a metal layer (which is a porous metal layer), and a bio-based conductive paste layer, and the specific preparation method is described as follows:

[0106] First, a polyamideimide varnish is applied to a carrier film having a thickness of 50 μm, and the varnish is heated in a floating coating oven at a temperature range of 50 to 180°C for 10 minutes (usually, heating for 3 to 10 minutes) to form a first bio-based insulator layer by solidifying at a low temperature. Next, a polyamideimide varnish is applied to the surface of the first bio-based insulator layer, and the varnish is heated in a floating coating oven at a temperature range of 50 to 180°C for 10 minutes (usually, heating for 3 to 10 minutes) to form a second bio-based insulator layer by solidifying at a low temperature.

[0107] Next, a porous metal layer that will become a porous copper foil metal layer is manufactured. The thin film and aluminum wire are placed in a melting furnace evaporator, heated to 1700°C under high vacuum conditions to evaporate, and an aluminum layer with a thickness of 400 nm is laminated on the thin film, and then a peeling treatment is performed on the surface of the aluminum layer, and a copper foil metal layer is formed on the peeled surface of the aluminum layer by sputtering, and the copper foil metal layer is treated by chemical microetching to form a plurality of holes. Finally, the thin film and the aluminum layer are peeled off, and a porous copper foil metal layer is formed on the copper foil metal layer, where the porous copper foil metal layer has holes with a diameter of 1 to 20 μm, a porosity of 25±2%, and a tensile strength of 22 kgf / mm 2 , which is a growth rate of 6%.

[0108] Next, a bio-based adhesive layer is formed on the porous copper foil metal layer by transfer method, and the bio-based insulating layer is pressed against the bio-based adhesive layer to position the bio-based adhesive layer between the bio-based insulating layer and the porous metal layer. Then, a bio-based conductive paste layer is applied to the porous metal layer, and finally, a CA-0700 release film (purchased from Nanya) is pressed against the bio-based conductive paste layer, where the temperature of the pressing manufacturing process is 60°C and the pressure is 2kg.

[0109] <Examples A3 and A4> According to the contents of the components of each layer in Examples A3 and A4 in Table 1 and the thicknesses of each layer in Examples A3 and A4 in Table 2, a matte-type electromagnetic interference shielding film containing bio-based components is prepared, which includes a bio-based insulating layer (not including an insulator layer), a bio-based adhesive layer, a metal layer (which is a porous metal layer), and a bio-based conductive paste layer.

[0110] The manufacturing method is the same as in Examples A1 and A2, except that the two bio-based insulating layers are replaced with one bio-based insulating layer.

[0111] <Examples A5 and A6> According to the content of each layer component of Examples A5 and A6 in Table 1 and the thickness of each layer of Examples A5 and A6 in Table 2, a matte-type electromagnetic interference shielding film containing bio-based components is prepared, which includes a bio-based insulating layer (including two bio-based insulating layers), a bio-based adhesive layer, a metal layer (which is a metal plating layer), and a bio-based conductive paste layer, and the specific preparation method is described as follows:

[0112] First, a polyamideimide varnish is applied to a carrier film having a thickness of 50 μm, and the varnish is heated in a floating coating oven at a temperature range of 50 to 180° C. for 10 minutes (usually, 3 to 10 minutes) to form a first bio-based insulation layer by solidifying at a low temperature. Next, a polyamideimide varnish is applied to the surface of the first bio-based insulation layer, and the varnish is heated in a floating coating oven at a temperature range of 50 to 180° C. for 10 minutes (usually, 3 to 10 minutes) to form a second bio-based insulation layer by solidifying at a low temperature. The carbon black content of the first bio-based insulation layer is 10% relative to the total weight of the first bio-based insulation layer, and no carbon black is added to the second bio-based insulation layer. Then, a bio-based adhesive layer is formed on the second bio-based insulation layer by a coating method.

[0113] Next, a metal plating layer is formed on the bio-based adhesive layer by a combination of vapor deposition and chemical plating, and the metal plating layer is a copper plating metal layer, in which the output parameters of the vapor deposition are 10-50KW, the gas flow rate of the vapor deposition is 100-500SCCM, and the linear velocity is 3-10m / min, and the current density of the chemical plating is 5-100A / dm2 (ASD), and the linear velocity is 3-10m / min.

[0114] Finally, a bio-based conductive paste layer is applied to the other side opposite the copper-plated metal layer, and finally, a CA-0700 release layer (purchased from Nan Ya) is pressed onto the other side opposite the bio-based conductive paste layer, where the temperature of the pressing manufacturing process is 60°C and the pressure is 2kgf.

[0115] <Example A7> According to the content of each layer component of Example A7 in Table 1 and the thickness of each layer of Example A7 in Table 2, a matte-type electromagnetic interference shielding film containing bio-based components was manufactured, which includes a bio-based insulating layer (not including a bio-based insulator layer), a bio-based adhesive layer, a metal layer (which is a metal plating layer), and a bio-based conductive paste layer.

[0116] The manufacturing method is the same as that of Examples A5 and A6, except that the two bio-based insulation layers are replaced with one bio-based insulation layer.

[0117] <Examples A8 and A9> According to the contents of the components of each layer in Examples A8 and A9 in Table 1 and the thicknesses of each layer in Examples A8 and A9 in Table 2, a matte-type electromagnetic interference shielding film containing bio-based components is manufactured, which includes a bio-based insulating layer (including two bio-based insulating layers), a metal layer (which is a metal plating layer), and a bio-based conductive paste layer.

[0118] The manufacturing method is the same as that of Examples A5 and A6, except that the bio-based adhesive layer is not included and the metal plating layer has cracks and / or defects.

[0119] <Comparative Example 1> A commercially available high-shielding radio-frequency shielding film containing no bio-based components and a common metal layer was used, and the thickness of each layer is shown in Table 2. Here, the insulating layer of Comparative Example 1 is a polyurethane ink.

[0120] <Comparative Example 2> A commercially available high-shielding radio frequency shielding film was used that does not contain bio-based components and contains a common metal layer, and the thickness of each layer is shown in Table 2, where the insulating layer of Comparative Example 2 is Kapton black polyimide thin film (purchased from DuPont).

[0121] <Comparative Example 3> A commercially available high-shielding radio frequency shielding film containing no bio-based components and a common metal layer was used, and the thickness of each layer is shown in Table 2, where the insulating layer of Comparative Example 3 is Kapton black polyimide thin film (purchased from DuPont).

[0122] In addition, the metal layers in Comparative Examples 1 to 3 are all copper foil layers that have not been subjected to general microetching treatment, and except for changing the bio-based resin to a petrochemical resin, the components and contents of the adhesive layer and conductive paste layer in Comparative Examples 1 to 3 are shown in Table 1.

[0123] Table 3 shows test results of Examples A1 to A9 and Comparative Examples 1 to 3, such as gloss value, resistance value, insulation resistance value, peel strength, hardness, shielding performance, solder heat resistance, and user-side SMT simulation.

[0124] <Test Method> 1. Porosity test: The porosity of the porous metal layer is calculated by the following formula:

[0125]

number

[0126] where M is the mass of the sample (g) and V is the volume of the sample (cm 3 ) and ρ s is the density (g / cm) of the porous medium corresponding to the dense solid material. 3 )

[0127] 2. Tensile strength test: The test is carried out according to standard IPC-TM-650 2.4.19 C(5 / 98).

[0128] 3. Elongation test: The test is carried out according to the standard IPC-TM-650 2.4.19 C (5 / 98).

[0129] 4. Peel strength test: The test is carried out on the conductive paste side of the sample according to standard IPC-TM-650 2.4.9 D.

[0130] 5. Solder heat resistance test: The test is performed according to standard IPC-TM-650 2.4.13 F.

[0131] 6. Surface hardness test: A hardness test is carried out on the insulating layer surface or the first insulating layer surface of the sample with a pencil according to standard ASTM D3363.

[0132] 7. Electromagnetic shielding performance test: The test is conducted according to the standard GB / T 30142-2013 "Method for measuring the shielding effectiveness of planar electromagnetic shielding materials."

[0133] 8. Gloss value test: Prepare a sample with dimensions of 3cm x 8cm or more, measure the surface of the sample insulation layer in the vertical direction (MD direction) with a gloss device, and read the value at 60° as the measured value.

[0134] 9. Insulation resistance test: The insulation resistance value of the shielding film semi-finished product without metal layer plating is measured, and the shielding film semi-finished product has only an insulating layer and an adhesive layer. First, cut out the A4 size from the shielding film semi-finished product, apply epoxy resin adhesive to the shiny surface of 1 oz thick electrolytic copper foil, and press the electrolytic copper foil coated with the epoxy resin adhesive onto the cut-out semi-finished product by lamination to form a laminated structure of insulating layer / adhesive layer / epoxy resin paste / electrolytic copper foil, and then age at a temperature of 160°C for 1 hour to obtain a test sample. Then, use a resistance meter to measure the left, center, and right positions of the insulating layer surface of the test sample, and obtain an average result from the above three data.

[0135] 10. Resistance Test: Measure the resistance of the wiring samples in ohm mode with a digital multimeter. Eight wiring samples with length 6cm (TD) x width 0.8cm (MD) are arranged in a linear fashion and numbered 1 to 8, each of the eight wiring samples has a hole with a diameter of 1.0mm, the distance between two holes is 1cm, the distance between holes of sample 1 and sample 8 is 7cm, and tests are performed with a set of two holes along the MD direction (number 1-number 2, number 1-number 3, number 1-number 4...number 1-number 8), and a total of seven values ​​are measured and recorded in Table 1 as the average.

[0136] 11. Biobased Content Test: USDA certified, the measurement method is the ratio of biobased carbon to petroleum-derived carbon according to the standard ASTM D6866-12. 14 It is measured by the formula: % Bio-content = [Bio(Organic)Carbon] / [Total(Organic)Carbon]*100%.

[0137] 12. User-side SMT simulation test: Heat up to 120°C at 2°C / sec, preheat for 2 minutes, heat up to 245°C at 3°C / sec, maintain for 0.5 minutes, cool to room temperature at 4°C / sec, then take out and check for any defects on the outside.

[0138] 13. Surface roughness test: The test is performed using an atomic force microscope (AFM) in accordance with the JIS-B0601 standard.

[0139] 14. Peel test: A tension testing machine is used to carry out the test according to standard ASTM D3330.

[0140] [Table 3]

[0141] From the test comparison results in Table 3, it is recognized that the matte type electromagnetic interference shielding film containing bio-based components of the present application has good related properties. Specifically, compared with the shielding films of Comparative Examples 1 to 3 that do not contain bio-based components and use metal layers that are not micro-etched, the shielding films containing bio-based components in Examples A1 to A9 of the present application, including the shielding films using porous metal layers in Examples A1 to A4, the shielding films using metal plating layers without cracks and / or defects in Examples A5 to A7, and the shielding films using thicker metal plating layers with cracks and / or defects in Examples A8 and A9, all have superior electromagnetic shielding performance, simulation test of SMT by the user, on-resistance after SMT, weather resistance, etc., to existing shielding films, and meet the special requirements of the manufacturing process of the user. In addition, due to the composition design of the insulating layer, conductive paste, and adhesive layer, even if the total bio-based content is measured by JORA certification and USDA certification, the actual biomass bio-based content is more than 20%, and bio-based plastic certification is obtained from each country. In addition, the insulating layer surfaces of the shielding films of Comparative Examples 1 to 3 had surface hardnesses of HB to 2H, indicating that the surfaces were brittle and easily scratched, whereas the bio-based insulating layer surfaces / first insulator layer surfaces of the shielding films of Examples A1 to A7 of the present application not only all had a surface hardness of 2H, but the bio-based first insulator layer surfaces of the shielding films of Examples A8 and A9 of the present application further had a surface hardness of 3H, thereby achieving excellent appearance and mechanical performance.

[0142] <Examples B1 to B8> The matte-type electromagnetic interference shielding films containing bio-based components in Examples B1 to B8 are all similar to Example A9 in terms of the content of each layer component, thickness, and manufacturing method, but the amount of carbon black added to each of the bio-based insulator layer and carrier film is adjusted as shown in Table 4 below.

[0143] <Comparative Example 4> The matte-type electromagnetic interference shielding film containing a bio-based component of Comparative Example 4 is similar to that of Comparative Example 1, but the insulating layer has a structure of two insulating layers, and the amounts of carbon black added to the insulating layers and the carrier film are shown in Table 4 below.

[0144] [Table 4]

[0145] In the above table, the first surface roughness means the surface roughness of the first insulating layer in the direction toward the carrier film, and the second surface roughness means the surface roughness of the second insulating layer in the direction toward the metal layer.

[0146] The test comparison results in Table 4 show that, compared with the shielding film of Comparative Example 4, Examples B3 to B8 of the present disclosure, which are matte-type electromagnetic interference shielding films having different surface roughness, have good user-side SMT simulation results. In addition, compared with the shielding film of Comparative Example 4, Examples B1 to B8 of the present disclosure all have excellent peel strength from the carrier film. [Explanation of symbols]

[0147] 100: Shielding membrane 101: Bio-based insulating layer 1011: First surface 1012: Second Surface 102: Bio-based adhesive layer 103: Metal layer 104: Bio-based conductive paste layer 105: Carrier layer 106: Release layer 200: Shielding membrane 201: Bio-based insulating layer 2011: First Surface 2012: The Second Surface 2013: Insulating layer 203: Metal layer 204: Bio-based conductive paste layer 205: Carrier layer 206: Release layer 300: Shielding membrane 301: Bio-based insulating layer 303: Metal layer 3031: Defect 304: Bio-based conductive paste layer 305: Carrier layer 306: Release layer

Claims

1. a bio-based conductive paste layer having a thickness of 3 to 50 μm and containing a bio-based resin and a petrochemical resin; A metal layer having a thickness of 0.1 to 15 μm; A matte-type electromagnetic interference shielding film containing a bio-based component, the film having a thickness of 2 to 50 μm and including a bio-based insulating layer containing a bio-based resin and a petrochemical resin, the metal layer is a metal plating layer formed on the bio-based conductive paste layer; the bio-based insulating layer is formed on the metal layer such that the metal layer is located between the bio-based insulating layer and the bio-based conductive paste layer; the bio-based insulating layer has a first surface and a second surface opposite to the first surface, the second surface being a contact surface with the metal layer, the first surface and the second surface having different surface roughnesses Rz, the surface roughness Rz of the first surface being in the range of 0.001 to 10 μm, and the surface roughness Rz of the second surface being in the range of 3 to 8 μm; A matte-type electromagnetic interference shielding film containing a bio-based component, the bio-based content of the matte-type electromagnetic interference shielding film being 20 to 100% as a ratio of bio-based carbon to petrochemical carbon in accordance with standard ASTM D6866-12.

2. a carrier layer having a thickness of 12.5 to 250 μm, the carrier layer being formed on the first surface of the bio-based insulating layer, and after the carrier layer is peeled off, the first surface of the bio-based insulating layer has a gloss of 0 to 60 GU at a measurement angle of 60°; the material forming the carrier layer includes an inorganic powder and at least one selected from the group consisting of polypropylene, polyethylene terephthalate, polyimide, polyphenylene sulfide, polyethylene naphthalate, polyurethane, and polyamide, the polypropylene being biaxially oriented polypropylene; 2. The matte-type electromagnetic interference shielding film containing a bio-based component according to claim 1, wherein the inorganic powder is at least one selected from the group consisting of calcium sulfate, carbon black, silicon dioxide, titanium dioxide, zinc sulfide, zirconium oxide, calcium carbonate, silicon carbide, boron nitride, alumina, talc powder, aluminum nitride, glass powder, quartz powder, and clay, and the particle size of the inorganic powder in the carrier layer is 10 nm to 20 μm.

3. The bio-based resin and the petrochemical resin in the bio-based insulating layer and the bio-based conductive paste layer, respectively, are each independently at least one selected from the group consisting of epoxy resin, acrylic resin, polyurethane, urethane resin, silicone rubber resin, parylene resin, bismaleimide resin, styrene-ethylene-butylene-styrene block copolymer, polyimide resin, and polyamideimide; a content of the bio-based resin in the bio-based insulation layer is more than 0% by weight and 100% by weight or less, and a content of the petrochemical resin in the bio-based insulation layer is 0 to 80% by weight, based on a total weight of the bio-based insulation layer; The matte-type electromagnetic interference shielding film containing bio-based components according to claim 1, wherein the content of the bio-based resin in the bio-based conductive paste layer is more than 0% by weight and not more than 95% by weight, and the content of the petrochemical resin is 0 to 70% by weight, based on the total weight of the bio-based conductive paste layer.

4. The bio-based insulating layer further comprises at least one inorganic powder selected from the group consisting of calcium sulfate, carbon black, silicon dioxide, titanium dioxide, zinc sulfide, zirconium oxide, calcium carbonate, silicon carbide, boron nitride, alumina, talc powder, aluminum nitride, glass powder, quartz powder, and clay, and the particle size of the inorganic powder is 10 nm to 20 μm; 2. The matte-type electromagnetic interference shielding film containing a bio-based component according to claim 1, wherein the content of the inorganic powder in the bio-based insulation layer is more than 0% by weight and not more than 50% by weight, based on the total weight of the bio-based insulation layer.

5. The bio-based insulating layer further comprises at least one flame-retardant compound selected from the group consisting of halogen, phosphorus, nitrogen, and boron compounds; 2. The matte-type electromagnetic interference shielding film containing a bio-based component according to claim 1, wherein the content of the flame-retardant compound in the bio-based insulation layer is 1 to 40% by weight based on the total weight of the bio-based insulation layer.

6. The bio-based insulating layer includes an inorganic pigment and / or an organic pigment, the inorganic pigment being at least one selected from the group consisting of cadmium red, cadmium lemon yellow, cadmium yellow, titanium dioxide, carbon black, black iron oxide, and black complex inorganic pigments, and the organic pigment being at least one selected from the group consisting of aniline black, perylene black, anthraquinone black, benzidine yellow pigment, phthalocyanine blue, and phthalocyanine green; 2. The matte-type electromagnetic interference shielding film containing a bio-based component according to claim 1, wherein the content of the inorganic pigment and / or the organic pigment in the bio-based insulation layer is more than 0% by weight and not more than 50% by weight, based on the total weight of the bio-based insulation layer.

7. At least one of the bio-based insulating layer and the bio-based conductive paste layer further comprises an additive, the additive being at least one selected from the group consisting of a solidifying agent, a catalyst, and a surfactant; the content of the additive in the bio-based insulation layer is greater than 0 wt % and less than or equal to 20 wt % based on the total weight of the bio-based insulation layer; 2. The matte-type electromagnetic interference shielding film containing bio-based components according to claim 1, wherein the content of the additive in the bio-based conductive paste layer is greater than 0% by weight and less than 10% by weight, based on the total weight of the bio-based conductive paste layer.

8. 2. The matte-type electromagnetic interference shielding film containing a bio-based component according to claim 1, wherein the metal plating layer is a copper foil layer, a silver foil layer, an aluminum foil layer, or a nickel foil layer having a thickness of 0.1 to 5 μm.

9. The bio-based conductive paste layer is a single layer conductive paste layer having a plurality of conductive particles, and the plurality of conductive particles are formed of at least one material selected from the group consisting of copper, silver, nickel, tin, gold, palladium, aluminum, chromium, titanium, zinc, carbon, nickel-gold alloy, gold-silver alloy, copper-nickel alloy, copper-silver alloy, silver-nickel alloy, and copper-nickel-gold alloy; 2. The matte-type electromagnetic interference shielding film containing bio-based components according to claim 1, wherein the content of the conductive particles is 5 to 85% by weight based on the total weight of the bio-based conductive paste layer.

10. The bio-based conductive paste layer has a two-layer structure, and is configured by laminating one adhesive layer having no conductive particles and one conductive adhesive layer having a plurality of conductive particles, the adhesive layer not having conductive particles is adhered between the metal layer and the conductive adhesive layer having the plurality of conductive particles; 2. The matte-type electromagnetic interference shielding film containing bio-based components according to claim 1, wherein the content of the conductive particles is 5 to 85% by weight based on the total weight of the conductive adhesive layer.

11. 2. The matte-type electromagnetic interference shielding film containing bio-based components according to claim 1, wherein the bio-based insulating layer has a hardness of 2H to 6H.

12. forming a bio-based insulating layer on the carrier layer and then solidifying the bio-based insulating layer at a temperature of 50° C. to 180° C.; forming a metal plating layer on the bio-based insulating layer by one method selected from vacuum sputtering, vapor deposition, chemical plating, and electroplating; forming a bio-based conductive paste layer on the metal plating layer such that the metal plating layer is positioned between the bio-based insulating layer and the bio-based conductive paste layer; pressing a release layer against the bio-based conductive paste layer; The method for producing a matte-type electromagnetic interference shielding film containing a bio-based component, wherein the surface roughness Rz between the contact surface of the bio-based insulating layer and the metal plating layer is in the range of 3 to 8 μm.

13. 13. The method for producing a matte-type electromagnetic interference shielding film containing a bio-based component according to claim 12, further comprising the steps of forming another bio-based insulating layer on the bio-based insulating layer before forming the metal plating layer, solidifying the other bio-based insulating layer under a condition of 50°C to 180°C, and further forming the metal plating layer to position the metal plating layer between the other bio-based insulating layer and the bio-based conductive paste layer.

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