Polyolefin resin film

Abstract

The objective is to provide a polyolefin-based resin film with excellent antistatic properties and heat resistance. [Solution] The polyolefin resin film 1 has a functional layer 3 on at least one of its outermost surfaces, which contains polyethylene, polypropylene, and an antistatic agent, wherein the antistatic agent content of the functional layer 3 is 10% by mass or more and 30% by mass or less, and the polypropylene content of the polyolefin resin film 1 is 16% by mass or more and 41% by mass or less.

Description

[Technical Field]

[0001] This invention relates to a polyolefin-based resin film (hereinafter sometimes simply referred to as "resin film"). [Background technology]

[0002] In electronic components such as semiconductor chips, electromagnetic interference (EMI) is suppressed by forming an electromagnetic shielding film on the outer surface of the electronic component using the sputtering method.

[0003] Here, a method has been proposed to protect external connection terminals in order to prevent the formation of an electromagnetic shielding film on the external connection terminals when forming an electromagnetic shielding film on an electronic component having external connection terminals.

[0004] More specifically, for example, in the process of forming an electromagnetic shielding film on an electronic component having an external connection terminal using the sputtering method, a method has been proposed in which adhesive tape for back surface protection is attached to cover the external connection terminal formed on the back side of the electronic component to prevent the electromagnetic shielding film from wrapping around to the back side of the electronic component (see, for example, Non-Patent Document 1). [Prior art documents] [Non-patent literature]

[0005] [Non-Patent Document 1] Toshiba Review, Vol. 71, No. 6, December 2016, pp. 16-19 [Overview of the Initiative] [Problems that the invention aims to solve]

[0006] However, in the method of covering with adhesive tape described in Non-Patent Document 1 above, it may be difficult to completely cover large external connection terminals with the adhesive tape. As a result, the adhesion between the adhesive tape and the back surface of the electronic component on which the external connection terminal is formed may decrease, creating a gap, which can lead to the undesirable situation where the electromagnetic shielding film wraps around to the back surface of the electronic component.

[0007] Therefore, it is conceivable to improve the embedding ability of external connection terminals into the adhesive tape and hold the external terminals with the adhesive tape by using a multilayer adhesive tape (carrier film for electronic components) having a multilayer structure comprising, for example, a base material made of a resin film and a functional layer provided on the base material. However, since the process of forming an electromagnetic wave shielding film on electronic components having external connection terminals by sputtering is carried out at high temperatures (100°C or higher), if, for example, the heat resistance of the base material constituting the adhesive tape is poor, the adhesive tape deforms due to thermal shrinkage of the base material, which reduces the ability to hold the external connection terminals.

[0008] Furthermore, for example, if the substrate constituting the adhesive tape has poor antistatic properties, there was a problem in the process of forming an electromagnetic wave shielding film on an electronic component having an external connection terminal using the sputtering method, where dust and other particles would adhere to the substrate, or electrostatic damage would occur.

[0009] Therefore, the present invention has been made in view of the above problems, and aims to provide a polyolefin resin film with excellent antistatic properties and heat resistance. [Means for solving the problem]

[0010] In order to achieve the above object, the polyolefin resin film of the present invention is a polyolefin resin film having a functional layer containing polyethylene, polypropylene, and an antistatic agent on at least one outermost surface, wherein the content of the antistatic agent with respect to the whole of the functional layer is 10% by mass or more and 30% by mass or less, and the content of polypropylene with respect to the whole of the polyolefin resin film is 16% by mass or more and 41% by mass or less.

Advantages of the Invention

[0011] According to the present invention, it becomes possible to provide a polyolefin resin film excellent in antistatic property and heat resistance.

Brief Description of the Drawings

[0012] [Figure 1] It is a cross-sectional view showing a polyolefin resin film according to an embodiment of the present invention. [Figure 2] It is a plan view showing a polyolefin resin film according to an embodiment of the present invention. [Figure 3] It is a cross-sectional view showing a modified example of the polyolefin resin film of the present invention.

Modes for Carrying Out the Invention

[0013] Hereinafter, the polyolefin resin film of the present invention will be specifically described. Note that the present invention is not limited to the following embodiments, and can be appropriately modified and applied without changing the gist of the present invention.

[0014] The resin film of the present invention is used as a base material in the above-described carrier film for electronic components, and is a resin film having a functional layer on at least one outermost surface, and is a resin film having a multilayer structure composed of a core layer (intermediate layer) and a functional layer provided on at least one side of the core layer.

[0015] <^ Examples of the resin film having such a multilayer structure include, for example, as shown in Fig. 1, a resin film 1 having a three-layer structure composed of a laminate of a core layer 2 and functional layers 3 laminated on both sides of the core layer 2, and laminated in the order of functional layer / core layer / functional layer.

[0016] (Functional layer) Examples of the functional layer 3 include those containing polyethylene, polypropylene, and an antistatic agent.

[0017] <Polyethylene> The functional layer 3 contains polyethylene among polyolefin resins and preferably contains low-density polyethylene (LDPE) having a density of 0.930 g / cm 3 or less. When the density is 0.930 g / cm 3 or less, the excessive increase in crystallinity can be suppressed, the flexibility can be improved, and the isotropy of the resin film can be improved.

[0018] Also, from the viewpoint of improving processing stability, the density of the low-density polyethylene is preferably 0.860 g / cm 3 or more, and more preferably 0.880 g / cm 3 or more.

[0019] That is, the low-density polyethylene having a density of 0.860 g / cm 3 or more and 0.930 g / cm 3 or less has low surface adhesiveness. When used in the functional layer, it can suppress the adhesion to the conveying roll when transporting the resin film, suppress the blocking when winding up the resin film, and improve the processing stability of the resin film.

[0020] Among low-density polyethylene, linear low-density polyethylene has side-chain branches in its linear structure like high-density polyethylene. Since these side-chain branches are short and the number of short-chain branches is small, there is little steric hindrance. Compared with low-density polyethylene, it has a higher density, higher crystallinity, and a higher melting point, so it has excellent heat resistance. Also, because it has the above-mentioned side-chain branches, compared with high-density polyethylene, its crystallinity does not become too high, and it also has excellent flexibility.

[0021] Also, the density of linear low-density polyethylene is preferably 0.910 to 0.925 g / cm 3 . When it is 0.910 g / cm 3 or more, the crystallinity increases, so the heat resistance can be improved. When it is 0.925 g / cm 3 or less, an excessive increase in crystallinity can be suppressed, and the isotropy (uniform expandability) of the resin film can be improved.

[0022] Also, the melt mass flow rate (MFR) of linear low-density polyethylene is preferably 0.5 to 7.5 g / 10 min, more preferably 1.0 to 6.0 g / 10 min, and even more preferably 2.0 to 5.0 g / 10 min. This is because when it is 0.5 g / 10 min or more, the molecular weight is not too large, and the flexibility and processability can be improved. When it is 7.5 g / 10 min or less, the molecular weight is not too small, and the heat resistance can be improved.

[0023] Note that the above melt mass flow rate is obtained by measuring in accordance with the provisions of JIS K7210:1999.

[0024] Also, from the perspective of suppressing surface adhesiveness, the content of polyethylene in the entire functional layer 3 (that is, each of the functional layers 3 laminated on both sides of the core layer 2) (that is, 100% by mass of each functional layer) is preferably 32.5% by mass or more and 65% by mass or less.

[0025] Based on the above, in the resin film 1 of the present invention, by using linear low-density polyethylene as the resin for forming the functional layer 3, it is possible to improve the heat resistance at high temperatures of 100°C or higher in the process of forming an electromagnetic wave shielding film on an electronic component having an external connection terminal by sputtering, and to provide a resin film 1 with excellent flexibility and isotropy.

[0026] <Antistatic agent> In the resin film 1 of the present invention, the functional layer 3 contains an antistatic agent, from the viewpoint of imparting antistatic properties to the resin film 1.

[0027] Examples of these antistatic agents include block copolymers of propylene resins and polyhydric alcohols, low molecular weight surfactants, and fillers such as carbon black. These antistatic agents may be used individually or in combination of two or more.

[0028] Furthermore, from the viewpoint of providing semi-permanent antistatic properties, it is preferable to use a block copolymer of a propylene-based resin, which is a polymer-type antistatic agent, and a polyhydric alcohol as the antistatic agent.

[0029] A block copolymer of a propylene resin and a polyhydric alcohol is a block copolymer having a segment of propylene polymer containing structural units derived from propylene and a segment of polyhydric alcohol polymer containing structural units derived from the polyhydric alcohol.

[0030] This block copolymer of propylene resin and polyhydric alcohol has a structure in which the continuous phase (soft segment phase) of the polyether of the polyhydric alcohol contributes to the development of antistatic properties, while the hard segment phase of the propylene resin contributes to improved dispersibility in the resin forming the functional layer 3 and to the development of strength in that resin.

[0031] Examples of propylene polymer segments include homopolypropylene segments, which are obtained by polymerizing propylene alone, and copolymer segments of propylene and α-olefins.

[0032] Furthermore, examples of polyhydric alcohols that constitute the polymer segment of a polyhydric alcohol include ethylene glycol, diethylene glycol, 1,2-propanediol, 1,3-propanediol (trimethylene glycol), and propylene glycol.

[0033] Furthermore, from the viewpoint of improving antistatic properties, it is preferable to use a block copolymer of polypropylene and polyethylene glycol as the block copolymer of propylene resin and polyhydric alcohol.

[0034] Furthermore, as block copolymers of propylene resin and polyhydric alcohol, commercially available products such as Pelektron PVH (manufactured by Sanyo Chemical Industries, Ltd., a block copolymer having polypropylene segments and polyethylene glycol segments) and Pelektron PVL (manufactured by Sanyo Chemical Industries, Ltd., a block copolymer having polypropylene segments and polyethylene glycol segments) can be used.

[0035] Furthermore, from the viewpoint of improving antistatic properties, in the resin film 1 of the present invention, the content of the antistatic agent relative to the total (i.e., 100% by mass) of the functional layer 3 (i.e., each of the functional layers 3 laminated on both sides of the core layer 2) is 10% by mass or more and 30% by mass or less, preferably 15% by mass or more and 30% by mass or less, and more preferably 20% by mass or more and 30% by mass or less.

[0036] As described above, in the resin film 1 of the present invention, the content of the antistatic agent in the functional layer 3 is 10% by mass or more and 30% by mass or less. Therefore, in the process of forming an electromagnetic wave shielding film on an electronic component having an external connection terminal by sputtering, the antistatic properties of the resin film 1 can be improved, and the adhesion of dust and other particles and the occurrence of electrostatic discharge problems caused by the resin film 1 can be prevented. Consequently, it becomes possible to improve the productivity of electronic components on which an electromagnetic wave shielding film has been formed.

[0037] Furthermore, in functional layer 3 containing polyethylene, polypropylene, and an antistatic agent, if the amount of antistatic agent relative to the total functional layer 3 is greater than 30% by mass, the heat resistance may decrease, as shown in Comparative Example 2 below.

[0038] <Polypropylene> Examples of polypropylene include homopolypropylene obtained by polymerizing propylene alone, random polypropylene obtained by copolymerizing ethylene and propylene, and block polypropylene (block polypropylene copolymerized with ethylene) obtained by polymerizing homopolypropylene and then copolymerizing ethylene and propylene in the presence of homopolypropylene.

[0039] Of these, it is preferable to use homopolypropylene from the viewpoint of further improving heat resistance. This is because homopolypropylene has high stereoregularity and a large degree of crystallinity that contributes to the melting point, resulting in excellent heat resistance. In addition, although it has high rigidity due to its high degree of crystallinity, the flexibility of the resin film 1 can be improved by mixing it with the linear low-density polyethylene mentioned above.

[0040] Furthermore, block polypropylene copolymerized with ethylene is a block polypropylene composed of propylene and ethylene, and has a sea-island structure in which polyethylene (island component) is dispersed in homopolypropylene (sea component), with an EPR phase (rubber phase) surrounding the polyethylene. Therefore, while retaining the heat resistance of homopolypropylene, it has excellent flexibility because the EPR phase is formed at the boundary of the sea-island structure.

[0041] Furthermore, from the viewpoint of further improving heat resistance, it is preferable that the polypropylene content of the functional layer 3 (i.e., each of the functional layers 3 laminated on both sides of the core layer 2) is 20% by mass or more and 50% by mass or less in relation to the total amount (i.e., 100% by mass of each functional layer).

[0042] Based on the above, in the resin film 1 of the present invention, by using polypropylene as the resin that forms the functional layer, it is possible to improve the heat resistance at high temperatures of 100°C or higher in the process of forming an electromagnetic wave shielding film on an electronic component having an external connection terminal by sputtering.

[0043] (Core layer) The core layer 2 may include one containing the aforementioned polyethylene and polypropylene.

[0044] Here, from the viewpoint of processability, it is preferable that the polyethylene content relative to the entire core layer 2 (i.e., 100% by mass of the core layer) be 62.5% by mass or more and 90% by mass or less.

[0045] Furthermore, from the viewpoint of further improving heat resistance, it is preferable that the polypropylene content relative to the entire core layer 2 (i.e., 100% by mass of the core layer) be 10% by mass or more and 37.5% by mass or less.

[0046] <Resin film> In the resin film 1 of the present invention, the polypropylene content relative to the total resin film 1 (i.e., 100% by mass of the resin film) is 16% by mass or more and 41% by mass or less. If the content is less than 16% by mass, the heat resistance of the resin film 1 will decrease, and if it is more than 41% by mass, the processability of the resin film 1 will decrease.

[0047] In other words, in the resin film 1 of the present invention, the polypropylene content relative to the total resin film 1 is 16% by mass or more and 41% by mass or less. Therefore, a decrease in processability can be prevented, and the heat resistance at high temperatures of 100°C or higher can be improved in the process of forming an electromagnetic wave shielding film on an electronic component having external connection terminals by sputtering. Consequently, a decrease in the retention of external connection terminals due to thermal shrinkage can be prevented.

[0048] Furthermore, in the resin film 1 of the present invention, it is preferable that the thermal shrinkage rate when heated at 120°C for 15 minutes in the direction of the mechanical axis (longitudinal) of the resin film 1 (hereinafter referred to as "MD") and the direction perpendicular thereto (hereinafter referred to as "TD"), as shown in Figure 2, is 2% or less. If the thermal shrinkage rate is greater than 2%, the resin film 1 will shrink excessively, causing deformation of the resin film 1 due to thermal shrinkage, which may reduce the adhesion between the core layer 2 and the functional layer 3, and reduce the retention of the external connection terminals due to thermal shrinkage.

[0049] Furthermore, from the viewpoint of suppressing the aforementioned decrease in retention, the thermal shrinkage rate of the resin film 1 is preferably 1.8% or less, and more preferably 1.5% or less.

[0050] Furthermore, the aforementioned "thermal shrinkage rate" can be determined by the method described in the examples below.

[0051] Furthermore, in the resin film 1 of the present invention, the surface resistivity is 1.00 × 10 13 It is preferable that the ratio is Ω / □ or less, and 1.00 × 10 11 It is more preferable that the ratio is less than or equal to Ω / □, and 1.00 × 1010 It is even more preferable that the surface resistivity is Ω / □ or less. 13 If the value is greater than Ω / □, when forming an electromagnetic shielding film on an electronic component with external connection terminals using the sputtering method, the static electricity generated by the resin film may damage the circuitry in the electronic component.

[0052] In other words, the surface resistivity is 1.00 × 10⁻⁶ 13 When the value is Ω / □ or less, it exhibits excellent antistatic properties, thus preventing the inconvenience of damage to circuits in electronic components caused by static electricity.

[0053] The "surface resistivity" referred to here is obtained by measurement in accordance with the provisions of JIS K6911:2006, and can be determined by the method described in the examples below.

[0054] The thickness of the resin film 1 of the present invention is preferably 30 to 300 μm, and more preferably 50 to 150 μm. If the thickness of the resin film is 30 μm or more, handling properties can be improved, and if the thickness is 300 μm or less, processability can be improved.

[0055] Furthermore, in the case of a resin film having a three-layer structure in which a functional layer / core layer / functional layer is laminated in that order, the thickness of the functional layer is not particularly limited, but is preferably 2 to 60 μm, and more preferably 4 to 40 μm. Similarly, the thickness of the core layer is not particularly limited, but is preferably 40 to 120 μm, and more preferably 50 to 80 μm.

[0056] Furthermore, for example, in the case of a resin film having a three-layer structure in which a functional layer / core layer / functional layer is laminated in that order, from the viewpoint of processability and low cost, the ratio of the core layer to the entire resin film is preferably 50-95%, and more preferably 55-90%.

[0057] <Manufacturing method> For example, when manufacturing a resin film 1 having a three-layer structure in the order of functional layer / core layer / functional layer, as shown in Figure 1, first, a resin material for forming the functional layer and a resin material for forming the core layer are prepared.

[0058] Next, using a co-extruder equipped with a T-die for three types of three layers, the resin material for forming the functional layer and the resin material for forming the core layer are simultaneously extruded and molded at a predetermined temperature to produce a resin film 1 having the multilayer structure of the present invention, which is composed of a laminate of a core layer 2 and functional layers 3 laminated on both sides of the core layer 2. Alternatively, the resin film 1 of the present invention may be produced by known calendering or inflation methods.

[0059] <Other forms> The resin film 1 of the present invention may contain various additives, as long as the effects of the present invention are not impaired. As additives, known additives commonly used in resin films 1 can be used, such as antiblocking agents, nucleating agents, processing aids, heat stabilizers, antioxidants, ultraviolet absorbers, lubricants, and colorants. These additives may be used individually or in combination of two or more.

[0060] Furthermore, although a resin film having a three-layer structure in which a functional layer / core layer / functional layer is laminated in that order was described as an example, the resin film having a multilayer structure of the present invention only needs to have at least one of the above-mentioned functional layers. For example, as shown in Figure 3, one of the functional layers 3 in Figure 1 is the surface layer 4, and the resin film 10 has a three-layer structure in which the surface layer / core layer / functional layer is laminated in that order. As the surface layer 4, for example, general-purpose resins such as polyethylene, polypropylene, polybutene, ethylene-vinyl acetate copolymer (EVA), ethylene-methyl methacrylate copolymer (EMMA), acrylic resins, and ionomers can be used. Furthermore, by using these general-purpose resins, it is possible to reduce costs.

[0061] Furthermore, in the resin film of the present invention, from the viewpoint of further improving antistatic properties, the core layer 2 and the surface layer 4 may be configured to contain the above-mentioned antistatic agent.

[0062] Furthermore, the resin film 1 of the present invention is not limited to a three-layer structure, but may also be a resin film having a five-layer structure in which a functional layer / functional layer / core layer / functional layer / functional layer is laminated in that order. [Examples]

[0063] The present invention will be described below based on examples. However, the present invention is not limited to these examples, and these examples can be modified and altered in accordance with the spirit of the invention; such modifications do not exclude them from the scope of the present invention.

[0064] The materials used to produce the resin film are listed below. (1) LLDPE1: Linear low-density polyethylene, melting point: 121°C, density: 0.922 g / cm³ 3 MFR: 1.6g / 10 minutes (2) LLDPE2: Linear low-density polyethylene, melting point: 120°C, density: 0.913 g / cm³ 3 MFR: 2.0g / 10 minutes (3) HomoPP: Homopolypropylene obtained by polymerizing propylene alone, melting point: 163°C, density: 0.900 g / cm³ 3 MFR: 0.5g / 10 minutes (4) Antistatic agent 1: Block copolymer having polypropylene segments and polyethylene glycol segments, melting point: 150°C, density: 1.0 g / cm³ 3 MFR: 8.0g / 10 minutes (5) Antistatic agent 2: Block copolymer having polypropylene segments and polyethylene glycol segments, melting point: 135°C, density: 1.1 g / cm³ 3 MFR: 15.0g / 10 minutes

[0065] (Example 1) <Preparation of polyolefin resin films> First, the materials shown in Table 1 were blended to prepare a resin material for forming a functional layer and a resin material for forming a core layer, having the compositions (parts by mass) shown in Table 1.

[0066] Next, using a co-extruder equipped with a T-die for three types of three layers, the resin material for forming the functional layer and the resin material for forming the core layer were simultaneously extruded and molded under conditions of a die temperature of 180-230°C and a chill roll temperature of 30°C to obtain a polyolefin resin film having the thickness shown in Table 1 and a three-layer structure in which the functional layer / core layer / functional layer is laminated in that order.

[0067] As shown in Table 1, in the polyolefin resin film of this embodiment, the polypropylene content of the functional layer is 37.5 [mass%], and the ratio of the functional layer to the total polyolefin resin film is 20 [μm] / 80 [μm] = 0.25. Therefore, the polypropylene content based on the functional layer in the polyolefin resin film is 37.5 × 0.25 = 9.375 [mass%]. In addition, the polypropylene content of the core layer is 37.5 [mass%], and the ratio of the core layer to the total polyolefin resin film is 60 [μm] / 80 [μm] = 0.75. Therefore, the polypropylene content based on the core layer in the polyolefin resin film is 37.5 × 0.75 = 28.125 [mass%]. Consequently, the polypropylene content [mass%] of the total polyolefin resin film (i.e., 100 mass%) was 9.375 + 28.125 = 37.5 [mass%].

[0068] <Calculation of thermal shrinkage rate> A sample of the specified size (10cm x 10cm) was cut from the prepared resin film. Orthogonal markings, each 8cm long and parallel to the edge, were marked 1cm inward from each side of the sample. The sample was then placed in a 120°C oven and heated for 15 minutes. After removal, it was allowed to cool to room temperature (approximately 25°C). The distance between the markings [cm] at the medium (MD) and total (TD) of the heat-treated sample was measured. The thermal shrinkage rate [%] was calculated from the change in the distance between the markings at the MD and TD before and after heating using the following formula (1), and this was used as an indicator of heat resistance. The results are shown in Table 1.

[0069] [Mathematics 1] Thermal shrinkage rate [%] in MD (or TD) = [(gauge between gauge marks before heating (8cm) - gauge between gauge marks after heating) / gauge between gauge marks before heating (8cm)] × 100 (1)

[0070] <Measurement of surface resistivity> The surface resistivity of the fabricated resin film was measured in accordance with the provisions of JIS K6911:2006. More specifically, first, a sample of A4 size (width 210 mm, length 297 mm) was obtained for measurement using the fabricated resin film. Next, the surface resistivity of the obtained sample was measured using a high resistivity meter (manufactured by Nitto Seikou Analytech Co., Ltd., product name: HighResta UX). The surface resistivity was measured when a voltage of 1000 V was applied and held for 10 seconds with the probe pressed against the sample under conditions of a temperature of 23°C and a humidity of 50%. The results are shown in Table 1.

[0071] (Examples 2-10, Comparative Examples 1-4) Except for changing the composition of the resin components in the functional layer and core layer to the compositions (parts by mass) shown in Tables 1 and 2, a resin film having the thickness shown in Tables 1 and 2 and a three-layer structure with the functional layer / core layer / functional layer laminated in that order was prepared in the same manner as in Example 1 described above.

[0072] Then, the thermal shrinkage rate was calculated and the surface resistivity was measured in the same manner as in Example 1 described above. The results are shown in Tables 1 and 2.

[0073] [Table 1]

[0074] [Table 2]

[0075] As shown in Table 1, in the resin films of Examples 1 to 10, in which the functional layer contains an antistatic agent and the amount of the antistatic agent relative to the total functional layer is 10% by mass or more and 30% by mass or less, the surface resistivity is 1.00 × 10 13Since the ratio is less than or equal to Ω / □, it can be seen that it has excellent antistatic properties.

[0076] Furthermore, as shown in Table 1, in the resin films of Examples 1 to 10, where the functional layer contains polypropylene and the polypropylene content relative to the total polyolefin resin film is 16% by mass or more and 41% by mass or less, the heat shrinkage rate in MD and TD is 2% or less, indicating excellent heat resistance.

[0077] On the other hand, as shown in Table 2, in the resin films of Comparative Examples 1, 3-4, since the functional layer does not contain an antistatic agent, the surface resistivity is 1.00 × 10⁻⁶. 13 The value is greater than Ω / □, indicating poor antistatic properties.

[0078] Furthermore, as shown in Table 2, in the resin film of Comparative Example 2, the content of the antistatic agent relative to the total functional layer is greater than 30% by mass (50% by mass), so the thermal shrinkage rate in MD is greater than 2%, indicating poor heat resistance.

[0079] Furthermore, as shown in Table 2, in the resin film of Comparative Example 3, since polypropylene is not included in the polyolefin resin film, the heat shrinkage rate in MD is greater than 2%, indicating poor heat resistance. [Industrial applicability]

[0080] As described above, the present invention is suitable for polyolefin resin films. [Explanation of Symbols]

[0081] 1. Resin film 2 core layers 3 Functional Layers 4 Surface layer

Claims

1. A polyolefin resin film having a functional layer on at least one of its outermost surfaces containing polyethylene, polypropylene, and an antistatic agent, The content of the antistatic agent relative to the entire functional layer is 10% by mass or more and 30% by mass or less. The polypropylene content relative to the total polyolefin resin film is 16% by mass or more and 41% by mass or less. A polyolefin-based resin film characterized by the following features.

2. The polyolefin resin film according to claim 1, characterized in that the antistatic agent is a block copolymer of a propylene resin and a polyhydric alcohol.

3. The polyolefin resin film according to claim 1 or 2, characterized in that the antistatic agent is a block copolymer of polypropylene and polyethylene glycol.

4. The polyolefin resin film according to claim 1, characterized in that the polypropylene content relative to the entire functional layer is 20% by mass or more and 50% by mass or less.

5. The polyolefin resin film according to claim 1 or 4, characterized in that the polypropylene is homopolypropylene obtained by polymerizing propylene alone.

6. The polyolefin resin film according to claim 1, characterized in that the polyethylene content relative to the entire functional layer is 32.5% by mass or more and 65% by mass or less.

7. The polyolefin resin film according to claim 1 or 6, characterized in that the polyethylene is linear low-density polyethylene.

8. A carrier film for electronic components using the polyolefin resin film described in claim 1 as a base material.

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