Transfer film and electromagnetic wave shielding film with transfer film

Abstract

Provided is a transfer film that can be used to manufacture an electromagnetic wave shielding film in which a relief is transferred to a protective layer of the electromagnetic wave shielding film, so that the surface of the protective layer can be made to have a matte finish, and cracks are less likely to occur in the protective layer when heat-pressed. The transfer film of the present invention is characterized by having a matte-finish transfer layer having a matte-finish transfer surface, and the matte-finish transfer layer contains a resin filler.

Description

Technical Field

[0001] This invention relates to transfer films and electromagnetic wave shielding films with transfer films. Background Technology

[0002] For a long time, operations have been carried out, such as attaching electromagnetic wave shielding films to printed circuit boards (FPCs) to shield electromagnetic waves from the outside.

[0003] Typically, electromagnetic wave shielding films are formed by sequentially stacking a protective layer, a shielding layer, and an adhesive layer.

[0004] One method for manufacturing an electromagnetic wave shielding film with this structure is a transfer film method. In this method, a protective layer is coated onto the transfer film, and a shielding layer and an adhesive layer are further formed on the protective layer. Then, the adhesive layer, shielding layer, and protective layer are transferred onto a substrate by hot pressing, thus depositing the electromagnetic wave shielding film onto the substrate.

[0005] In this method of manufacturing electromagnetic wave shielding film, in order to improve the design of the protective layer, an operation is performed to make the surface of the protective layer matte (low gloss).

[0006] As a method for making the surface of the protective layer matte, for example, Patent Document 1 discloses the following method: using a transfer film with an uneven surface, the uneven surface is transferred to the protective layer to impart a matte finish.

[0007] As a transfer film used in this method, Patent Document 1 discloses an embossed transfer film characterized by having an embossed layer on at least one side of the film, the embossed layer being a coating layer containing resin and particles, and the value of the polar component (γsd) and hydrogen-binding component (γsh) of the surface of the aforementioned embossed layer, which together account for the surface free energy, being 5 mJ / m 2 Below that, and the gloss level of the aforementioned uneven surface at 60° is 5% or less.

[0008] In addition, Patent Document 2 discloses a method that uses a transfer film with an uneven surface to transfer the unevenness to a protective layer to impart a matte finish.

[0009] As a transfer film used in this method, Patent Document 2 discloses an embossed transfer film, characterized in that one side of the film has a surface embossing, and the film with a surface embossing on one side of the substrate film has an embossed layer on one side of the substrate film. The embossed layer comprises a resin (A) and particles (B). The resin (A) comprises one or more resins selected from acrylic resins, polyester resins, urethane resins, melamine resins, and epoxy resins. The embossed layer satisfies the following formula (1): the 60° gloss of the surface with the embossed surface is 20% or less, the rate of increase of the 60° gloss after being subjected to pressure pressing at 40 MPa for 30 seconds is 25% or less relative to the 60° gloss before the pressure pressing is applied, and a release layer is provided on the embossed layer.

[0010] (1 / 4)×D≤d≤(3 / 4)×D···(1)

[0011] Here, d represents the film thickness of the uneven layer [μm], and D represents the average particle size of the particles (B) [μm].

[0012] Existing technical documents

[0013] Patent documents

[0014] Patent Document 1: Japanese Patent Application Publication No. 2018-27642

[0015] Patent Document 2: Japanese Patent No. 6699548 Summary of the Invention

[0016] The problem the invention aims to solve

[0017] In the methods described in Patent Documents 1 and 2, the electromagnetic wave shielding film is disposed on the substrate by heat pressing. However, this presents a problem where cracks easily form in the protective layer of the electromagnetic wave shielding film.

[0018] The present invention was made in view of the above-mentioned problems. The object of the present invention is to provide a transfer film that can be used to manufacture a protective layer of an electromagnetic wave shielding film by transferring embossing onto the film, thereby making the surface of the protective layer matte and preventing cracks from forming in the protective layer during hot pressing.

[0019] Solution for solving the problem

[0020] The inventors discovered that the cracks in the protective layer of the electromagnetic wave shielding film are caused by the transfer film used in the manufacture of the electromagnetic wave shielding film, and thus conceived of this invention.

[0021] That is, the transfer film of the present invention is characterized by having a matte transfer printing layer having a matte transfer printing surface, wherein the matte transfer printing layer comprises a resin filler.

[0022] When the surface of the protective layer of the electromagnetic wave shielding film is matte, unevenness is formed on the surface of the transfer film in contact with the protective layer (i.e., the matte transfer surface of the matte transfer layer).

[0023] As a method for forming unevenness on the surface of the matte transfer printing layer, a method of adding filler to the matte transfer printing layer is known.

[0024] If the filler is too hard, scratches can easily form on the surface of the protective layer during the manufacture of electromagnetic wave shielding films, becoming the starting point for cracks.

[0025] However, in the transfer film of the present invention, the filler is a resin filler, and therefore has moderate softness.

[0026] Therefore, when manufacturing an electromagnetic wave shielding film using the transfer film of the present invention, scratches that could become the initiation point of cracks are less likely to form on the surface of the protective layer. As a result, when the electromagnetic wave shielding film manufactured using the transfer film of the present invention is hot-pressed onto an object, cracks are less likely to form in the protective layer.

[0027] Furthermore, in the transfer film of the present invention, the matte transfer layer contains resin filler, thus the matte transfer surface has an uneven texture. Therefore, when manufacturing an electromagnetic wave shielding film using the transfer film of the present invention, the uneven texture can be transferred to the surface of the protective layer, making the surface of the protective layer matte. As a result, the opacity of the protective layer can be improved.

[0028] In the transfer film of the present invention, the matte transfer layer preferably further comprises inorganic fillers.

[0029] Inorganic fillers are harder than resin fillers and can form fine, periodic bumps and depressions on matte transfer printing surfaces.

[0030] Therefore, when manufacturing an electromagnetic wave shielding film using the transfer film of the present invention, which contains inorganic fillers in a matte transfer layer, fine periodic embossing is transferred onto the surface of the protective layer of the electromagnetic wave shielding film. As a result, light becomes more easily dispersed on the surface of the protective layer of the electromagnetic wave shielding film, reducing the brightness of the protective layer and improving design.

[0031] In other words, the surface of the protective layer of the electromagnetic wave shielding film is appropriately matte, which also improves its opacity.

[0032] In the transfer film of the present invention, the inorganic filler preferably has at least one shape selected from the group consisting of flat, scaly, rod-shaped, dendritic, fibrous and thorn-shaped.

[0033] If a matte transfer printing layer contains inorganic fillers of this shape, fine periodic undulations can be formed on the matte transfer printing surface.

[0034] Therefore, when manufacturing electromagnetic wave shielding films using transfer films with this characteristic, finer periodic embossing is transferred onto the surface of the protective layer of the electromagnetic wave shielding film. As a result, light becomes more easily dispersed on the surface of the protective layer of the electromagnetic wave shielding film, reducing brightness. Thus, design flexibility is further improved.

[0035] In the transfer film of the present invention, the inorganic filler is preferably a porous body.

[0036] If the inorganic filler is porous, its pore volume increases, thus reducing its weight per unit volume (i.e., apparent specific gravity). Therefore, when the weight of the inorganic filler in a matte transfer printing layer is constant, a porous inorganic filler results in a larger filling volume compared to a dense inorganic filler. Consequently, more surface irregularities can be created on the matte transfer printing layer based on the inorganic filler.

[0037] When using this transfer film to manufacture electromagnetic wave shielding films, a large amount of embossing can be transferred onto the surface of the protective layer of the electromagnetic wave shielding film.

[0038] As a result, the gloss level on the surface of the protective layer of the electromagnetic wave shielding film can be reduced, and the gloss on the surface of the protective layer of the electromagnetic wave shielding film can be appropriately eliminated. Therefore, the design of the protective layer of the electromagnetic wave shielding film is improved.

[0039] In the transfer film of the present invention, preferably, the inorganic filler comprises at least one selected from the group consisting of silicon dioxide, metal powder, metal oxide, calcium carbonate, glass beads, carbon and talc.

[0040] The inorganic fillers containing these materials have moderate hardness, thus making them suitable for achieving the effect of matte transfer printing layers containing inorganic fillers.

[0041] In the transfer film of the present invention, the particle size (D) of the above-mentioned resin filler is preferably [missing information]. 50 The particle size (D) of the inorganic filler is larger than that of the above-mentioned inorganic filler. 50 ).

[0042] The height of the raised areas forming the matte transfer printing surface depends on the size of the filler contained in the matte transfer printing layer. That is, the larger the particle size of the filler contained in the matte transfer printing layer, the higher the raised areas will be on the matte transfer printing surface.

[0043] Particle size (D) of resin filler 50 The particle size is larger than that of inorganic fillers (D). 50 In the case of ), it becomes easier to form high protrusions originating from resin fillers.

[0044] When this transfer film is used to manufacture an electromagnetic wave shielding film, and the film is heat-pressed onto the substrate, the protrusions derived from the soft resin filler first engage with the protective layer of the electromagnetic wave shielding film. Therefore, the protrusions derived from the hard inorganic filler become less likely to engage with the protective layer. As a result, cracks can be prevented from forming on the surface of the protective layer.

[0045] In the transfer film of the present invention, in the matte transfer layer, the weight ratio of the resin filler is preferably less than the weight ratio of the inorganic filler.

[0046] By making the weight proportion of resin filler less than that of inorganic filler, it becomes easier to form protrusions originating from inorganic filler on the matte transfer printing surface. As mentioned above, inorganic filler is hard and can form fine periodic irregularities on the matte transfer printing surface. Therefore, when manufacturing electromagnetic wave shielding films using this transfer film, more fine periodic irregularities are transferred to the surface of the protective layer of the electromagnetic wave shielding film. As a result, the surface gloss of the protective layer of the electromagnetic wave shielding film can be reduced, leading to improved design.

[0047] In the transfer film of the present invention, preferably, the resin filler comprises at least one selected from the group consisting of polyurethane resin, acrylic resin, polyamide resin, polyimide resin, melamine resin, vinyl resin, styrene resin, polyester resin and polyolefin resin.

[0048] The resin filler containing these materials has moderate flexibility, thus making it less likely for scratches to form on the surface of the protective layer when manufacturing an electromagnetic wave shielding film using this transfer film, which could become the starting point for cracks. As a result, when the electromagnetic wave shielding film manufactured using the transfer film of the present invention is heat-pressed onto the substrate, cracks are less likely to form in the protective layer.

[0049] In the transfer film of the present invention, the surface roughness (Ra) of the matte transfer surface is preferably 0.2 to 1.5 μm.

[0050] If the surface roughness (Ra) of the matte transfer printing surface is within the above range, when using this transfer film to manufacture an electromagnetic wave shielding film, the brightness and gloss of the protective layer surface can be appropriately reduced, resulting in a design improvement.

[0051] If the surface roughness (Ra) of the matte transfer printing surface is less than 0.2μm, it will be difficult to sufficiently reduce the brightness and gloss of the protective layer in the manufactured electromagnetic wave shielding film.

[0052] If the surface roughness (Ra) of a matte reversal printing surface exceeds 1.5 μm, it becomes prone to cracking in the protective layer of the manufactured electromagnetic wave shielding film.

[0053] The transfer film of the present invention preferably further comprises a substrate, wherein the matte transfer layer is disposed on the substrate such that the surface facing the matte transfer layer is in contact with the substrate.

[0054] The transfer film of the present invention can be easily manufactured by forming a matte transfer layer on a substrate.

[0055] The electromagnetic wave shielding film with transfer film of the present invention is characterized in that it comprises: a transfer film and an electromagnetic wave shielding film laminated on the transfer film, the transfer film comprising a matte transfer layer having a matte transfer surface, the matte transfer layer comprising a resin filler, the electromagnetic wave shielding film comprising: a protective layer and an adhesive layer laminated on the protective layer, the electromagnetic wave shielding film being laminated on the transfer film such that the protective layer is in contact with the matte transfer surface.

[0056] The electromagnetic wave shielding film with transfer film of the present invention comprises the transfer film of the present invention described above.

[0057] Therefore, when the transfer film is peeled off from the electromagnetic wave shielding film with the transfer film of the present invention, the unevenness of the transfer film formed on the matte transfer layer is sufficiently reduced by the brightness and gloss of the protective layer of the transferred electromagnetic wave shielding film, resulting in a design improvement.

[0058] In addition, when the electromagnetic wave shielding film with the transfer film of the present invention is hot-pressed onto the substrate, cracks are less likely to occur in the protective layer of the electromagnetic wave shielding film.

[0059] In the electromagnetic wave shielding film with transfer film, it is preferable to form a hard coating on the above-mentioned protective layer, and the hard coating is in contact with the above-mentioned matte transfer surface.

[0060] If the protective layer has a hard coating, the unevenness of the surface of the matte transfer printing surface of the transfer film is transferred to the protective layer, making it less likely for scratches to form on the surface of the protective layer, which could become the starting point of cracks.

[0061] As a result, when the electromagnetic wave shielding film is hot-pressed onto the substrate, cracks become less likely to form in the protective layer.

[0062] In the electromagnetic wave shielding film with transfer film, a metal layer is preferably disposed between the protective layer and the adhesive layer.

[0063] The metal layer functions as a shielding layer. Therefore, if a metal layer is placed between the protective layer and the adhesive layer, the shielding characteristics of the electromagnetic wave shielding film are improved.

[0064] The effects of the invention

[0065] According to the present invention, a transfer film can be provided, which can be used to manufacture a protective layer for an electromagnetic wave shielding film by transferring embossing onto the film, thereby making the surface of the protective layer matte and preventing cracks from forming in the protective layer during hot pressing. Attached Figure Description

[0066] Figure 1 A cross-sectional view illustrating an example of the transfer film of the first embodiment of the present invention is shown for illustrative purposes.

[0067] Figure 2 The diagram illustrates the process of forming a protective layer when manufacturing an electromagnetic wave shielding film using the transfer film of the first embodiment of the present invention.

[0068] Figure 3 The diagram illustrates the process of forming an adhesive layer when manufacturing an electromagnetic wave shielding film using the transfer film of the first embodiment of the present invention.

[0069] Figure 4 The process diagram illustrates an example of heat-pressing an electromagnetic wave shielding film onto an object using the electromagnetic wave shielding film with a transfer film according to the first embodiment of the present invention.

[0070] Figure 5 The process diagram illustrates an example of peeling the transfer film from the electromagnetic wave shielding film with the transfer film of the first embodiment of the present invention.

[0071] Figure 6 A cross-sectional view illustrating an example of an electromagnetic wave shielding film disposed on an adhered object.

[0072] Figure 7A A photograph of the surface of the protective layer, which is the benchmark for determining the matte tone of the protective layer of the electromagnetic wave shielding film as "Excellent (◎)".

[0073] Figure 7B A photograph of the surface of the protective layer used as a benchmark for determining the matte tone of the protective layer of the electromagnetic wave shielding film, which is considered "good (0)".

[0074] Figure 7C A photograph of the surface of the protective layer, which serves as the benchmark for determining the matte tone of the protective layer of the electromagnetic wave shielding film, to be "acceptable (△)". Detailed Implementation

[0075] The transfer film and the electromagnetic wave shielding film with the transfer film of the present invention will be specifically described below. However, the present invention is not limited to the following embodiments, and can be appropriately modified and applied without changing the spirit of the present invention.

[0076] (First Embodiment)

[0077] Figure 1 A cross-sectional view illustrating an example of the transfer film of the first embodiment of the present invention is shown for illustrative purposes.

[0078] Figure 1 The transfer film 10 shown is formed from a substrate 20 and a matte transfer layer 30 formed on the substrate 20.

[0079] The matte transfer printing layer 30 has a matte transfer printing surface 31 and a surface 32 opposite to the matte transfer printing surface 31.

[0080] The matte transfer printing layer 30 is disposed on the substrate 20 with its surface 32 in contact with the substrate 20.

[0081] In addition, the matte transfer layer 30 includes resin filler 33 and inorganic filler 34.

[0082] like Figure 1 As shown, protrusions 33a and 34a derived from resin filler 33 and inorganic filler 34 are respectively formed on the matte transfer printing surface 31, and the matte transfer printing surface 31 has an overall uneven surface.

[0083] When using the transfer film 10 to manufacture an electromagnetic wave shielding film, a protective layer is formed on the matte transfer surface 31, and the unevenness of the matte transfer surface 31 is transferred to the protective layer.

[0084] Therefore, when using the transfer film 10 to manufacture an electromagnetic wave shielding film, the surface of the protective layer can be made matte. As a result, the shielding properties of the protective layer can be improved.

[0085] In addition, the matte transfer layer 30 contains a resin filler 33. The resin filler 33 has moderate flexibility, so when using the transfer film 10 to manufacture an electromagnetic wave shielding film, scratches that could become the starting point of cracks are less likely to form on the surface of the protective layer.

[0086] As a result, when the electromagnetic wave shielding film manufactured using the transfer film 10 is hot-pressed onto the substrate, cracks are less likely to occur in the protective layer.

[0087] In addition, the matte transfer layer 30 contains inorganic filler 34.

[0088] The inorganic filler 34 is harder than the resin filler 33 and can form fine periodic bumps and depressions on the matte transfer printing surface 31.

[0089] Therefore, when using transfer film 10 to manufacture an electromagnetic wave shielding film, fine periodic irregularities are transferred onto the surface of the protective layer of the electromagnetic wave shielding film. As a result, light becomes more easily dispersed on the surface of the protective layer of the electromagnetic wave shielding film, which can reduce the brightness of the protective layer of the electromagnetic wave shielding film and improve its design.

[0090] In other words, the surface of the protective layer of the electromagnetic wave shielding film is appropriately matte, which also improves its opacity.

[0091] The following is a detailed description of the components of the transfer film.

[0092] (Substrate)

[0093] Materials used as the substrate 20 in the transfer film 10 include, for example, polyethylene terephthalate, polyethylene naphthalate, polyvinyl fluoride, polyvinylidene fluoride, rigid polyvinyl chloride, polyvinylidene chloride, nylon, polyimide, polystyrene, polyvinyl alcohol, ethylene / vinyl alcohol copolymer, polycarbonate, polyacrylonitrile, polybutene, flexible polyvinyl chloride, polyvinylidene fluoride, polyethylene, polypropylene, polyurethane, ethylene vinyl acetate copolymer, polyvinyl acetate and other plastic sheets, cellophane, high-quality paper, kraft paper, coated paper and other paper types, various non-woven fabrics, synthetic paper, metal layers, and composite films combining them.

[0094] The substrate 20 can be transparent or colored. There are no particular limitations on the coloring method; pigments or dyes can be used. For example, a white substrate can be formed by mixing a white pigment such as titanium dioxide, which also improves visibility and is therefore preferred.

[0095] The thickness of the substrate 20 is not particularly limited, but is preferably 12-500 μm, more preferably 25-75 μm, and even more preferably 25-50 μm.

[0096] If the thickness of the substrate is less than 12μm, the mechanical strength of the substrate will be lower, and the transfer film will become more prone to breakage when the electromagnetic wave shielding film formed on the transfer film is peeled off.

[0097] If the thickness of the substrate exceeds 500μm, productivity and operability become easily reduced.

[0098] An anchor coating can be formed on the surface of the substrate 20 that is in contact with the matte transfer layer 30.

[0099] By forming an anchor coating, the matte transfer layer 30 becomes less prone to peeling.

[0100] As an anchor coating, for example, polyester resins, acrylic resins, polyurethane resins, polyvinyl alcohol resins, polycarbonate resins, etc. can be used.

[0101] The anchor coating may also contain a crosslinking agent. Examples of crosslinking agents include isocyanate compounds, melamine compounds, carbodiimide compounds, oxazoline compounds, and epoxy compounds.

[0102] Anchor coatings may include additives such as particles, catalysts, surfactants, UV absorbers, initiators, and antistatic agents, depending on the requirements.

[0103] Using this substrate 20, a matte transfer printing layer 30 is formed on the substrate 20, thereby making it easy to manufacture a matte transfer printing layer.

[0104] (Matte transfer layer)

[0105] The matte transfer layer 30 comprises: resin, resin filler 33, and inorganic filler 34.

[0106] The resin contained in the matte transfer layer 30 can be acrylic resin, polyester resin, urethane resin, melamine resin, epoxy resin, silicone resin, olefin resin, fluorine resin, etc.

[0107] These resins can be used alone or in combination with two or more resins.

[0108] The resin filler 33 is not particularly limited, but preferably includes at least one selected from the group consisting of polyurethane resin, acrylic resin, polyamide resin, polyimide resin, melamine resin, vinyl resin, styrene resin, polyester resin, and polyolefin resin. Examples of polyolefin resins include polyethylene resin and polypropylene resin.

[0109] The resin filler 33 containing these materials has moderate flexibility, so when manufacturing an electromagnetic wave shielding film using this transfer film 10, scratches that could become the starting point for cracks are less likely to form on the surface of the protective layer. As a result, when the electromagnetic wave shielding film manufactured using the transfer film 10 is heat-pressed onto the substrate, cracks are less likely to form in the protective layer.

[0110] The Vickers hardness of the resin filler 33 is not particularly limited, but preferably 0.01 to 2.0 GPa, more preferably 0.05 to 1.0 GPa.

[0111] If the Vickers hardness of the resin filler is below 0.01 GPa, the resin filler is excessively soft. Therefore, it becomes difficult to form sufficiently deep recesses on the surface of the protective layer of the electromagnetic wave shielding film manufactured using this transfer film. Consequently, the brightness and gloss of the protective layer of the manufactured electromagnetic wave shielding film become less likely to decrease.

[0112] If the Vickers hardness of the resin filler exceeds 2.0 GPa, the resin filler is excessively hard. Therefore, the surface of the protective layer of the electromagnetic wave shielding film manufactured using this transfer film becomes less prone to scratches that could become the initiation point for cracks.

[0113] The shape of the resin filler 33 is not particularly limited, but it is preferably spherical.

[0114] The weight ratio of resin filler 33 relative to the total weight of matte transfer layer 30 is preferably 1 to 30 wt%, more preferably 2 to 15 wt%.

[0115] The particle size (D) of resin filler 33 50 Preferably 1-6 μm, more preferably 2-4 μm.

[0116] The inorganic filler 34 is not particularly limited, but preferably includes at least one selected from the group consisting of silica, metal powder, metal oxide, calcium carbonate, glass beads, carbon and talc.

[0117] The inorganic filler 34 containing these materials has moderate hardness, thus allowing the matte transfer layer 30 to effectively utilize the benefits of containing the inorganic filler 34. That is, when manufacturing an electromagnetic wave shielding film using the transfer film 10, fine periodic irregularities are transferred to the surface of the protective layer of the electromagnetic wave shielding film. As a result, light becomes more easily dispersed on the surface of the protective layer of the electromagnetic wave shielding film, reducing the brightness of the protective layer and improving its design.

[0118] The inorganic filler 34 is preferably a porous material.

[0119] If the inorganic filler 34 is porous, its pore volume increases, thus reducing its weight per unit volume (i.e., apparent specific gravity). Therefore, with a constant weight of the inorganic filler 34 contained in the matte transfer printing layer 30, the filling volume of the inorganic filler 34 is larger when it is porous compared to when it is dense. Consequently, more unevenness can be formed on the surface of the matte transfer printing layer 30 based on the inorganic filler 34.

[0120] When using this transfer film 10 to manufacture an electromagnetic wave shielding film, a large number of bumps and depressions can be transferred onto the surface of the protective layer of the electromagnetic wave shielding film.

[0121] As a result, the gloss level on the surface of the protective layer of the electromagnetic wave shielding film can be reduced, and the gloss on the surface of the protective layer of the electromagnetic wave shielding film can be appropriately eliminated. Therefore, the design of the protective layer of the electromagnetic wave shielding film is improved.

[0122] The shape of the inorganic filler 34 is not particularly limited and can be spherical, plate-shaped, fiber / needle-shaped, etc.

[0123] As a spherical shape, examples include round spheres and irregular shapes. As a plate-like shape, examples include flattened and scaly shapes. As a fibrous / needle-like shape, examples include rod-shaped, dendritic, fibrous, and thorn-like shapes.

[0124] Among these, it is preferred to have at least one shape selected from the group consisting of flat, scale-like, rod-like, dendritic, fibrous, and thorn-like.

[0125] If the matte transfer printing layer 30 contains inorganic filler 34 of this shape, finer periodic undulations can be formed on the matte transfer printing surface 31.

[0126] Therefore, when using the transfer film 10 with this characteristic to manufacture an electromagnetic wave shielding film, finer periodic irregularities are transferred onto the surface of the protective layer of the electromagnetic wave shielding film. As a result, light becomes more easily dispersed on the surface of the protective layer of the electromagnetic wave shielding film, reducing the brightness of the protective layer and further improving its design.

[0127] The weight ratio of inorganic filler 34 relative to the total weight of matte transfer layer 30 is preferably 3 to 50 wt%, more preferably 5 to 30 wt%.

[0128] The particle size (D) of inorganic filler 34 50 The preferred size is 0.5–5 μm, and more preferably 1–4 μm.

[0129] In the matte transfer layer 30, the preferred particle size (D) of the resin filler 33 is... 50 The particle size (D) is greater than that of inorganic filler 34. 50 ).

[0130] The height of the raised portion forming the matte transfer printing surface 31 depends on the size of the filler contained in the matte transfer printing layer 30. That is, the larger the particle size of the filler contained in the matte transfer printing layer 30, the higher the raised portion will be formed on the matte transfer printing surface 31.

[0131] The particle size (D) of resin filler 33 50 When the particle size (D50) of the inorganic filler 34 is larger than that of the inorganic filler 34, it becomes easier to form a high protrusion originating from the resin filler 33.

[0132] When an electromagnetic wave shielding film is manufactured using this transfer film 10, and the film is heat-pressed onto the substrate, the pressure exerted on the protective layer of the electromagnetic wave shielding film by the matte transfer layer 30 is easily mitigated by the high protrusions originating from the soft resin filler 33. Compared to cases where the particle size of the resin filler 33 is smaller than or equal to the particle size of the inorganic filler 34, the protrusions originating from the hard inorganic filler 34 are less likely to adhere to the protective layer of the electromagnetic wave shielding film. As a result, cracks can be prevented from forming on the surface of the protective layer.

[0133] In the matte transfer layer 30, the weight proportion of resin filler 33 is preferably less than the weight proportion of inorganic filler 34. Furthermore, the weight ratio of inorganic filler 34 to resin filler 33 is preferably [weight of inorganic filler] / [weight of resin filler] = 0.5 to 20, more preferably 2 to 10.

[0134] By making the weight proportion of resin filler 33 smaller than that of inorganic filler 34, it becomes easier to form protrusions originating from inorganic filler 34 on the matte transfer printing surface 31. As mentioned above, inorganic filler 34 is hard and can form fine periodic irregularities on the matte transfer printing surface 31. Therefore, when manufacturing an electromagnetic wave shielding film using this transfer film 10, more fine periodic irregularities are transferred to the surface of the protective layer of the electromagnetic wave shielding film. As a result, the surface brightness of the protective layer of the electromagnetic wave shielding film can be reduced, leading to improved design.

[0135] In the matte transfer layer 30, the preferred particle size (D) of the resin filler 33 is... 50 The particle size (D) is greater than that of inorganic filler 34. 50 Furthermore, the weight proportion of resin filler 33 is less than the weight proportion of inorganic filler 34.

[0136] Typically, larger particle sizes of fillers become more prone to detachment from the matte finish of the printing surface 31. Therefore, the particle size (D) of the resin filler 33... 50 The particle size (D) is greater than that of inorganic filler 34. 50 In this case, the resin filler 33 becomes more prone to detaching from the matte transfer printing surface 31. If the weight ratio of the resin filler 33 is less than the weight ratio of the inorganic filler 34, the amount of detached resin filler 33 can be reduced.

[0137] Furthermore, even if the weight proportion of resin filler 33 is small, it can still achieve the effect of making the protrusions of the aforementioned inorganic filler 34 less likely to stick to the electromagnetic wave shielding film as a protective layer.

[0138] That is, by reducing the weight ratio of resin filler 33, it is possible to achieve both the effect of suppressing the shedding of resin filler 33 and the effect of preventing cracks on the surface of the protective layer.

[0139] The surface roughness (Ra) of the matte transfer printing surface 31 is preferably 0.2 to 1.5 μm, more preferably 0.3 to 0.8 μm.

[0140] If the surface roughness (Ra) of the matte transfer printing surface 31 is within the above range, when using this transfer film 10 to manufacture an electromagnetic wave shielding film, the brightness and gloss of the protective layer surface can be appropriately reduced, resulting in a design improvement.

[0141] If the surface roughness (Ra) of the matte transfer printing surface is less than 0.2μm, it will be difficult to sufficiently reduce the brightness and gloss of the protective layer in the manufactured electromagnetic wave shielding film.

[0142] If the surface roughness (Ra) of a matte reversal printing surface exceeds 1.5 μm, it becomes prone to cracking in the protective layer of the manufactured electromagnetic wave shielding film.

[0143] In addition to resin, resin filler 33 and inorganic filler 34, the matte transfer layer 30 may also contain additives such as leveling agents and release regulators.

[0144] The thickness of the matte transfer printing layer 30 is preferably 0.5 to 5.0 μm, more preferably 1.0 to 4.0 μm.

[0145] If the thickness of the matte transfer printing layer is less than 0.5μm, the matte transfer printing layer becomes excessively thin, its strength decreases, and therefore it becomes easily damaged.

[0146] If the thickness of the matte transfer printing layer exceeds 5.0 μm, the volume of the matte transfer printing layer becomes excessively large, forming unevenness on the matte transfer printing surface. Therefore, a large amount of resin filler and inorganic filler are required.

[0147] Next, the method for manufacturing an electromagnetic wave shielding film using the transfer film 10 will be described.

[0148] (1) Protective layer formation process

[0149] Figure 2 The diagram illustrates, for illustrative purposes, the protective layer formation process when manufacturing an electromagnetic wave shielding film using the transfer film of the first embodiment of the present invention.

[0150] like Figure 2 As shown, in the protective layer forming process, a protective layer 40 is formed on the matte transfer surface 31 of the transfer film 10.

[0151] There are no particular limitations on the method of forming the protective layer 40; it can be formed using conventional methods such as a bar coater.

[0152] The thickness of the formed protective layer 40 is not particularly limited and can be set appropriately as needed, preferably 1 to 15 μm, more preferably 3 to 10 μm.

[0153] The protective layer is preferably composed of, for example, a thermoplastic resin composition, a thermosetting resin composition, or an active energy radiation-curable composition.

[0154] The thermoplastic resin composition described above is not particularly limited, and examples include styrene-based resin compositions, vinyl acetate-based resin compositions, polyester-based resin compositions, polyethylene-based resin compositions, polypropylene-based resin compositions, imide-based resin compositions, and acrylic resin compositions.

[0155] The thermosetting resin composition described above is not particularly limited, and examples include phenolic resin compositions, epoxy resin compositions, urethane resin compositions, melamine resin compositions, alkyd resin compositions, etc.

[0156] The above-mentioned active energy ray curable composition is not particularly limited, and examples include polymeric compounds having at least two (meth)acryloyloxy groups in the molecule.

[0157] The protective layer 40 can be formed from a single material or from two or more materials.

[0158] The protective layer 40 may contain curing accelerators, tackifiers, antioxidants, pigments, dyes, plasticizers, UV absorbers, defoamers, leveling agents, fillers, flame retardants, viscosity modifiers, anti-blocking agents, etc., as needed.

[0159] Alternatively, when forming the protective layer 40, the protective layer 40 can be formed by coating a resin for hard coating onto the matte transfer printing surface 31.

[0160] If such a hard coating is provided, then in the electromagnetic wave shielding film manufactured through subsequent processes, a hard coating is formed on the surface of the protective layer 40.

[0161] If the protective layer has a hard coating, it can prevent damage to the electromagnetic wave shielding film from external toughness or other factors.

[0162] It should be noted that hard coatings have low toughness, therefore, when using ordinary transfer films to create uneven surfaces in hard coatings, cracks are more likely to occur.

[0163] However, by using the transfer film 10, scratches that could become the starting point of cracks are less likely to form on the surface of the hard coating. Therefore, cracks can be prevented from forming in the hard coating.

[0164] The hard coating is preferably composed of at least one resin selected from the group consisting of polystyrene resins, vinyl acetate resins, polyester resins, polyolefin resins (e.g., polyethylene resins, polypropylene resin compositions, etc.), polyimide resins, acrylic resins, phenolic resins, epoxy resins, urethane resins, melamine resins, and alkyd resins.

[0165] Hard coatings containing these materials have sufficient strength, thus making it less likely for scratches to form on the surface of the protective layer, which could become the starting point for cracks.

[0166] As a result, when the electromagnetic wave shielding film is hot-pressed onto the substrate, it becomes less prone to cracking in the protective layer.

[0167] The thickness of the hard coating is not particularly limited, but is preferably 0.2 to 3.0 μm.

[0168] If the thickness of the hard coating is less than 0.2 μm, the strength of the hard coating becomes weaker, and the hard coating itself becomes more easily damaged.

[0169] If the thickness of the hard coating exceeds 3.0 μm, the overall flexibility of the protective layer becomes more easily reduced.

[0170] (2) Adhesive layer formation process

[0171] Figure 3 The diagram illustrates the process of forming an adhesive layer when manufacturing an electromagnetic wave shielding film using the transfer film of the first embodiment of the present invention.

[0172] Next, as Figure 3 As shown, in the adhesive layer forming process, an adhesive layer 50 is formed on the protective layer 40.

[0173] The electromagnetic wave shielding film 60 is composed of a protective layer 40 and an adhesive layer 50.

[0174] There are no particular limitations on the method of forming the adhesive layer 50; it can be formed using conventional methods such as a bar coater.

[0175] The adhesive layer 50 contains an adhesive resin as its main component. The resin constituting the adhesive layer 50 may be a thermoplastic resin composition such as a styrene-based resin composition, a vinyl acetate-based resin composition, a polyester-based resin composition, a polyethylene-based resin composition, a polypropylene-based resin composition, an imide-based resin composition, an amide-based resin composition, or an acrylic resin composition, or a thermosetting resin composition such as a phenolic resin composition, an epoxy resin composition, a urethane-based resin composition, a melamine-based resin composition, or an alkyd resin composition.

[0176] The adhesive resin constituting the adhesive layer 50 can be a single type or a combination of two or more of these.

[0177] The thickness of the adhesive layer 50 is not particularly limited, but is preferably set appropriately according to the application.

[0178] For example, the thickness of the adhesive layer 50 is preferably 1 to 20 μm, more preferably 5 to 15 μm.

[0179] The adhesive layer 50 can be made of either a conductive adhesive or a non-conductive adhesive.

[0180] Furthermore, if the adhesive layer 50 is composed of a conductive adhesive, the adhesive layer 50 may have isotropic conductivity or anisotropic conductivity.

[0181] When the adhesive layer 50 has isotropic conductivity, the adhesive layer 50 also functions as a shielding layer.

[0182] When the adhesive layer 50 is composed of a conductive adhesive, the adhesive layer 50 also contains conductive particles in addition to the aforementioned adhesive resin.

[0183] The conductive particles preferably contain metals such as silver, copper, nickel, aluminum, or silver-plated copper.

[0184] The adhesive layer 50 may also include flame retardants, flame retardant additives, curing accelerators, tackifiers, antioxidants, pigments, dyes, plasticizers, ultraviolet absorbers, defoamers, leveling agents, fillers, viscosity modifiers, etc.

[0185] Through the above processes, an electromagnetic wave shielding film 70 with a transfer film can be manufactured.

[0186] This electromagnetic wave shielding film 70 with a transfer film is also a method of the present invention.

[0187] Next, a method for heat-pressing an electromagnetic wave shielding film 60 onto a substrate using an electromagnetic wave shielding film 70 with a transfer film will be described.

[0188] Figure 4 This is a cross-sectional view illustrating an example of how an electromagnetic wave shielding film with a transfer film of the first embodiment of the present invention is heat-pressed onto an object.

[0189] Figure 5 The process diagram illustrates an example of peeling the transfer film from the electromagnetic wave shielding film with the transfer film of the first embodiment of the present invention.

[0190] Figure 6 A cross-sectional view illustrating an example of an electromagnetic wave shielding film disposed on an adhered object.

[0191] When using an electromagnetic wave shielding film 70 with a transfer film to heat-press an electromagnetic wave shielding film 60 onto an object, such as Figure 4 As shown, an electromagnetic wave shielding film 70 with a transfer film is disposed on the substrate T in such a way that the adhesive layer 50 is bonded to the substrate T, and then heat-pressed from the substrate 20 in the direction toward the substrate T.

[0192] There are no particular limitations on the conditions for hot pressing, but the preferred conditions are 120-200°C, 0.5-4.0 MPa, and 1-120 minutes, and more preferably 120-200°C, 1.0-3.0 MPa, and 3-60 minutes.

[0193] Next, as Figure 5 As shown, the transfer film 10 is peeled off from the electromagnetic wave shielding film 70 with the transfer film.

[0194] Therefore, as Figure 6As shown, an electromagnetic wave shielding film 60 can be disposed on the adherend T.

[0195] The transfer film 10 is formed on the surface of the protective layer 40 of the electromagnetic wave shielding film 60 by transferring the unevenness of the matte transfer surface 31.

[0196] Therefore, the brightness of the protective layer 40 of the electromagnetic wave shielding film 60 is sufficiently reduced, resulting in a design improvement.

[0197] That is, the surface of the protective layer 40 of the electromagnetic wave shielding film 60 is suitably matte, and the shielding performance is also improved.

[0198] In addition, when using an electromagnetic wave shielding film 70 with a transfer film, and hot-pressing the electromagnetic wave shielding film 60 onto the substrate T, cracks are less likely to occur in the protective layer 40 of the electromagnetic wave shielding film 60.

[0199] The gloss of the protective layer 40 of the electromagnetic wave shielding film 60 disposed on the adherend T is preferably 0.1 to 20.0 at 60° and preferably 5 to 80 at 85°.

[0200] When the gloss of the protective layer 40 is within the aforementioned range, the gloss of the protective layer 40's appearance is sufficiently reduced, resulting in a suitable matte finish. Therefore, design flexibility is enhanced.

[0201] It should be noted that the 60° gloss and 85° gloss in this specification refer to values ​​measured based on JIS Z 8741.

[0202] The L* value of the protective layer 40 of the electromagnetic wave shielding film 60 disposed on the adherend T is preferably 15 to 30.

[0203] When the L* value of the protective layer 40 is within the above-mentioned range, the brightness of the protective layer 40's appearance is sufficiently reduced, resulting in a suitable matte finish. Therefore, design flexibility is enhanced.

[0204] It should be noted that the L* value in this manual refers to the value measured using an integrating sphere spectrophotometer (X-Rite, Ci64, tungsten light source).

[0205] Furthermore, when a protrusion or recess is formed on the substrate T, and a conventional electromagnetic wave shielding film is heat-pressed, the protrusion or recess formed on the surface of the protective layer of the electromagnetic wave shielding film can sometimes become raised, forming a pattern. This pattern becomes particularly noticeable when the brightness and gloss of the protective layer of the electromagnetic wave shielding film are high.

[0206] However, as mentioned above, the protective layer 40 of the electromagnetic wave shielding film 60 has a matte finish and high opacity. Therefore, it can cover up this pattern.

[0207] It should be noted that "occlusivity" in this specification refers to the property of being able to cover patterns originating from the inside of the protective layer.

[0208] (Other implementation methods)

[0209] In the transfer film 10 described so far, the matte transfer layer 30 contains both resin filler 33 and inorganic filler 34.

[0210] However, in the transfer film of the present invention, the matte transfer layer may also contain only resin filler.

[0211] Even with this configuration, the embossed texture of the matte transfer printing surface can be transferred to the protective layer of the electromagnetic wave shielding film, which can reduce the brightness and gloss of the protective layer of the electromagnetic wave shielding film.

[0212] Furthermore, when using this transfer film to manufacture electromagnetic wave shielding films, scratches that could become the initiation point for cracks become less likely to form on the surface of the protective layer. In particular, this effect is more easily achieved when the matte transfer layer contains hard inorganic fillers.

[0213] Therefore, when the electromagnetic wave shielding film manufactured using the transfer film of the present invention is hot-pressed onto the substrate, cracks are less likely to occur in the protective layer.

[0214] In addition, the transfer film 10 includes a substrate 20.

[0215] However, the transfer film of the present invention can be formed on a matte transfer layer to form an electromagnetic wave shielding film, and the electromagnetic wave shielding film can be hot-pressed onto the substrate, and it may not have a substrate.

[0216] In the electromagnetic wave shielding film with transfer film of the present invention, a metal layer may also be disposed between the protective layer and the adhesive layer.

[0217] The metal layer functions as a shielding layer. Therefore, if a metal layer is placed between the protective layer and the adhesive layer, the shielding characteristics of the electromagnetic wave shielding film are improved.

[0218] In particular, when the adhesive layer is made of a non-conductive adhesive, a metal layer is needed to function as a shielding layer.

[0219] The metal layer may comprise a layer formed of materials such as gold, silver, copper, aluminum, nickel, tin, palladium, chromium, titanium, and zinc, and preferably includes a copper layer.

[0220] From the perspectives of conductivity and economy, copper is a suitable material for metal layers.

[0221] It should be noted that the metal layer may also include a layer formed of an alloy of the aforementioned metals.

[0222] The thickness of the metal layer is preferably 0.005 to 10 μm.

[0223] When the thickness of the metal layer is less than 0.005μm, it is not easy to obtain a sufficient shielding effect.

[0224] If the thickness of the metal layer exceeds 10 μm, it becomes difficult to bend.

[0225] In addition, when the electromagnetic wave shielding film has a metal layer, an anchor coating can also be formed between the protective layer and the metal layer.

[0226] Materials that can be used as anchor coatings include: polyurethane resin, acrylic resin, core-shell composite resin with polyurethane resin as the shell and acrylic resin as the core, epoxy resin, imide resin, amide resin, melamine resin, phenolic resin, urea-formaldehyde resin, end-capped isocyanates obtained by reacting polyisocyanates with end-capping agents such as phenol, polyvinyl alcohol, and polyvinylpyrrolidone.

[0227] Example

[0228] The following are embodiments that illustrate the invention in more detail, but the invention is not limited to these embodiments.

[0229] (Example 1)

[0230] Prepare a PET film with a thickness of 50μm as the substrate.

[0231] Next, 340 parts by weight of epoxy resin, which constitutes the matte transfer printing layer, and urethane beads (product name: ART PEARL C-1000T, manufacturer: Negami Kogyo Co., Ltd., particle size (D)) are added as resin fillers. 50 ): 20 parts by weight of 3.8μm, and silica particles as inorganic filler (product name: SYLYSIA 300, manufacturer: FUJI SILYSIACHEMICAL LTD., particle size (D) 50 Mix 80 parts by weight of (1.7μm) to prepare a composition for matte transfer printing layer.

[0232] Next, a matte transfer coating composition is applied to the substrate to achieve a dry weight of 2.5 g / m². 2 A matte transfer layer is formed to manufacture the transfer film of Example 1.

[0233] Next, a resin solution (solid content: 35% by mass) containing polyester resin and amino resin as curing agent is coated on the matte transfer layer with a thickness of 4μm as a hard coating, and then a resin solution (solid content: 20% by mass) mixed with epoxy resin is further coated to create a protective layer.

[0234] Next, 50 parts by weight of epoxy resin as an adhesive resin and 50 parts by weight of silver-coated dendritic copper powder as conductive particles are mixed to prepare a conductive adhesive.

[0235] Next, the conductive adhesive is applied to the protective layer with a thickness of 10 μm to form an adhesive layer.

[0236] Through the above processes, the electromagnetic wave shielding film with transfer film of Example 1 is manufactured.

[0237] Examples 2 through 4 and Comparative Example 1

[0238] As shown in Table 1, the filler contained in the matte transfer layer was changed. Otherwise, the transfer films of Examples 2 to 4 and the electromagnetic wave shielding film with the transfer film were manufactured in the same manner as in Example 1.

[0239] [Table 1]

[0240]

[0241] Next, an adherend formed of a film consisting of stacked copper foil and polyimide film was prepared. Electromagnetic wave shielding films with transfer films from each embodiment and Comparative Example 1 were then applied to the adherend by bonding adhesive layers together, and hot-pressed at 170°C, 3 MPa, and 3 minutes. Afterward, the transfer film was peeled off, thereby placing the electromagnetic wave shielding film onto the adherend.

[0242] (Gloss determination of the protective layer of electromagnetic wave shielding film)

[0243] The 60° and 85° gloss of the protective layer in each electromagnetic wave shielding film disposed on the adhered object were measured based on JIS Z 8741.

[0244] The measurements were performed using a BYK-Gardner Micro-Tri-Gross (portable gloss meter). The results are shown in Table 1.

[0245] (Determination of brightness and chromaticity of the protective layer of electromagnetic wave shielding film)

[0246] The L* value of the protective layer in each electromagnetic wave shielding film disposed on the adhered object was measured.

[0247] An integrating sphere spectrophotometer (X-Rite, Ci64, tungsten light source) was used for the measurements. It should be noted that the a* and b* values ​​(colorimetric values) were also measured.

[0248] The results are shown in Table 1.

[0249] (Determination of the matte finish (coverage) of the protective layer of an electromagnetic wave shielding film)

[0250] The matte finish (coverage) of the protective layer in each electromagnetic wave shielding film disposed on the adhered object was determined visually. The results are shown in Table 1.

[0251] It should be noted that the judgment criteria are as follows.

[0252] Figure 7A A photograph of the surface of the protective layer, which is the benchmark for determining the matte tone of the protective layer of the electromagnetic wave shielding film as "Excellent (◎)".

[0253] Figure 7B A photograph of the surface of the protective layer used as a benchmark for determining the matte tone of the protective layer of the electromagnetic wave shielding film, which is considered "good (0)".

[0254] Figure 7C A photograph of the surface of the protective layer, which serves as the reference for determining the matte tone of the protective layer of the electromagnetic wave shielding film.

[0255] Excellent (◎): such as Figure 7A As shown, the surface gloss of the protective layer is fully suppressed to a matte finish, making it impossible to discern the pattern originating from the inside.

[0256] Good (〇): such as Figure 7B As shown, the surface gloss of the protective layer is somewhat suppressed, resulting in a matte finish that makes it virtually impossible to discern the pattern originating from the inside.

[0257] Can (△): such as Figure 7C As shown, the surface gloss of the protective layer is not suppressed, and it is difficult to call it matte; the pattern originating from the inside can be discerned.

[0258] (Evaluation of the crack resistance of the protective layer of electromagnetic wave shielding film)

[0259] For each electromagnetic wave shielding film applied to the substrate, visually confirm whether cracks occur at the specified 32 points of the protective layer immediately after the transfer film is peeled off.

[0260] In addition, after curing (curing conditions: 150°C, heating for 60 minutes) and after heating in the reflow oven, similarly, visually confirm whether cracks have occurred at the specified 32 points of the protective layer.

[0261] It should be noted that the heating conditions in the reflow oven are set as follows: a reflow oven with a total length of 3m is used, the temperature inside the reflow oven is 140~270℃, and the temperature passes through at a speed of 0.5m / min.

[0262] Based on these results, the crack resistance of the protective layer of the electromagnetic wave shielding film was evaluated according to the following criteria. The results are shown in Table 1.

[0263] ◎: No cracks were produced after heating in the reflow oven.

[0264] 〇: Cracks occurred in any of the following: immediately after the transfer film was peeled off, after curing, and after heating in the reflow oven. However, after heating in the reflow oven, cracks occurred in the portion below 10.

[0265] ×: Cracks appeared in more than 10 places after heating in the reflow oven.

[0266] As shown in Table 1, it was determined that in the electromagnetic wave shielding films manufactured and prepared using the transfer films of Examples 1-4 containing resin fillers with a matte finish transfer layer, cracks are less likely to occur in the protective layer. Furthermore, it was determined that the surface of the protective layer has a matte finish, high opacity, and high design flexibility.

[0267] Explanation of reference numerals in the attached figures

[0268] 10 Transfer film

[0269] 20 Substrate

[0270] 30 matte transfer layers

[0271] 31 Matte Reversible Printing Surface

[0272] 32. Faces opposite to the matte transfer printing surface.

[0273] 33 Resin Fillers

[0274] 33a Protrusions derived from resin fillers

[0275] 34 Inorganic packing

[0276] 34a Protrusions derived from inorganic fillers

[0277] 40 protective layers

[0278] 50 adhesive layers

[0279] 60 Electromagnetic wave shielding film

[0280] 70 Electromagnetic wave shielding film with transfer film

[0281] T Adhesive

Claims

1. A transfer film, characterized in that, It features a matte transfer printing layer with a matte finish. The matte transfer layer contains resin filler. The matte transfer layer also contains inorganic fillers. The inorganic filler is a porous body. The particle size D of the resin filler 50 The particle size D of the inorganic filler is larger than that of the inorganic filler. 50 .

2. The transfer film according to claim 1, wherein, The inorganic filler has at least one shape selected from the group consisting of flat, scaly, rod-shaped, dendritic, fibrous and spiky.

3. The transfer film according to claim 1 or 2, wherein, The inorganic filler comprises at least one selected from the group consisting of silica, metal powder, metal oxide, calcium carbonate, glass beads, carbon, and talc.

4. The transfer film according to claim 1 or 2, wherein, In the matte transfer printing layer, the weight proportion of the resin filler is less than the weight proportion of the inorganic filler.

5. The transfer film according to claim 1 or 2, wherein, The resin filler comprises at least one selected from the group consisting of polyurethane resin, acrylic resin, polyamide resin, polyimide resin, melamine resin, vinyl resin, styrene resin, polyester resin and polyolefin resin.

6. The transfer film according to claim 1 or 2, wherein, The surface roughness Ra of the matte transfer printing surface is 0.2~1.5μm.

7. The transfer film according to claim 1 or 2, wherein, The transfer film also includes a substrate. The matte transfer printing layer is disposed on the substrate such that the side facing the matte transfer printing layer is in contact with the substrate.

8. An electromagnetic wave shielding film with a transfer film, characterized in that, It comprises: a transfer film and an electromagnetic wave shielding film laminated thereon. The transfer film has a matte transfer layer with a matte transfer surface. The matte transfer layer contains resin filler. The matte transfer layer also contains inorganic fillers. The inorganic filler is a porous body. The particle size D of the resin filler 50 The particle size D of the inorganic filler is larger than that of the inorganic filler. 50 , The electromagnetic wave shielding film comprises: a protective layer and an adhesive layer laminated thereon on the protective layer. The electromagnetic wave shielding film is stacked on the transfer film in such a way that the protective layer is in contact with the matte transfer printing surface.

9. The electromagnetic wave shielding film with transfer film according to claim 8, wherein, A hard coating is formed on the protective layer, and the hard coating is in contact with the matte transfer printing surface.

10. The electromagnetic wave shielding film with transfer film according to claim 8 or 9, wherein, A metal layer is disposed between the protective layer and the adhesive layer.

Images