Antistatic resin composition, resin film, and antistatic substrate film for dicing tape

Abstract

The purpose of the present invention is to provide a resin composition that has adequate antistatic properties and that suppresses the inconvenience of an antistatic agent contaminating a metal roll of a film-forming machine during film formation, a resin film of said resin composition, and a base film for an antistatic dicing tape. To achieve this purpose, the present invention is a resin composition that includes 20-99 parts by mass of (A) an ethylene resin, 1-80 parts by mass of (B) a propylene resin, and 1-39 parts by mass of (C) a block copolymer of propylene and a polyhydric alcohol; the sum of the amount of the component (A) ethylene resin blended and the amount of the component (B) propylene resin blended is 100 parts by mass; and the component (B) propylene resin does not include a block copolymer of propylene and a polyhydric alcohol. The mass ratio of the amount of the component (B) propylene resin blended and the amount of the component (C) block copolymer of propylene and a polyhydric alcohol blended is preferably 0.4 or greater.

Description

[Technical Field]

[0001] The present invention relates to an antistatic resin composition, a resin film including a layer formed from the antistatic resin composition, and a substrate film for an antistatic dicing tape including the resin composition layer. [Background technology]

[0002] Semiconductor chips are produced by forming a large number of chips on a large-diameter silicon wafer and then dicing the wafer into individual chips. The dicing process is often carried out after dicing tape is applied to the front and / or back surfaces of the silicon wafer (on which a large number of semiconductor chips are formed) for the purposes of protecting the surfaces of the semiconductor chips and fixing and picking up the individual semiconductor chips that have been cut.

[0003] In recent years, semiconductor chips have become smaller and thinner due to miniaturization of transistor structures and increased density of three-dimensional interconnect structures. As a result, static electricity generated during dicing has become more likely to cause problems, such as damage to the circuits of semiconductor chips. To address this issue, it has been proposed to impart antistatic properties to dicing tapes and base films for dicing tapes (see, for example, Patent Documents 1 to 3). However, these techniques require the incorporation of large amounts of antistatic agents to achieve sufficient antistatic properties. As a result, the antistatic agent can contaminate the metal rolls of the film-forming machine during film-forming of the base film. Furthermore, the antistatic agent contaminating the metal rolls of the film-forming machine can be transferred to the base film, thereby degrading the properties of the pressure-sensitive adhesive layer formed on the surface of the base film. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2008-244377 [Patent Document 2] Japanese Patent Application Laid-Open No. 2011-210887 [Patent Document 3] Japanese Patent Application Publication No. 2017-098369 Summary of the Invention [Problem to be solved by the invention]

[0005] The object of the present invention is to provide a resin composition that has sufficient antistatic properties and suppresses the inconvenience of the antistatic agent contaminating the metal rolls of the film-forming machine during film formation (hereinafter, this inconvenience may be abbreviated as "plate-out"), and a resin film that includes a layer formed from such a resin composition. A further object of the present invention is to provide a resin film suitable as a base film for an adhesive tape (hereinafter referred to as "dicing tape") that is attached to the front and / or back surface of a silicon wafer or the like for the purpose of surface protection when dicing (cutting and separating) the silicon wafer or the like. [Means for solving the problem]

[0006] As a result of extensive research, the present inventors have found that the above object can be achieved by a resin composition containing specific components in specific proportions.

[0007] Aspects of the present invention are as follows. [1]. (A) 20 to 99 parts by mass of an ethylene-based resin, (B) 80 to 1 parts by mass of a propylene-based resin, and (C) a block copolymer of propylene and a polyhydric alcohol, comprising 1 to 39 parts by mass; Here, the sum of the blending amount of the component (A) ethylene-based resin and the blending amount of the component (B) propylene-based resin is 100 parts by mass; The component (B) propylene-based resin does not include a block copolymer of propylene and a polyhydric alcohol. Resin composition. [2]. The resin composition according to item [1] above, wherein the mass ratio of the blending amount of the component (B) propylene-based resin to the blending amount of the component (C) block copolymer of propylene and polyhydric alcohol is 0.4 or more. [3]. the melt mass flow rate of the component (A) ethylene resin is lower than the melt mass flow rate of the component (C) block copolymer of propylene and polyhydric alcohol; Here, the melt mass flow rate of the component (A) ethylene resin and the melt mass flow rate of the component (C) propylene and polyhydric alcohol block copolymer are measured in accordance with JIS K7210-1:2014 under conditions of a temperature of 190°C and a load of 21.18N. The resin composition according to the above item [1] or [2]. [4]. the melting point of the propylene polymer segment of the component (C) propylene and polyhydric alcohol block copolymer is (Tm-30) to (Tm+30)°C; Here, Tm is the melting point (unit: °C) of the component (B) propylene-based resin. The resin composition according to any one of the above items [1] to [3]. [5]. The resin composition according to any one of the above items [1] to [4], which is used for a base film of a dicing tape. [6]. A substrate film for a dicing tape, comprising at least one layer formed from the resin composition according to any one of the above items [1] to [5]. [7]. A dicing tape having a substrate film for a dicing tape, the substrate film comprising at least one layer formed from the resin composition according to any one of the above items [1] to [5]. [8]. A resin film comprising at least one layer formed from the resin composition according to any one of the above items [1] to [4]. [Effects of the Invention]

[0008] The resin composition of the present invention has sufficient antistatic properties and suppresses plate-out. A preferred resin composition of the present invention has sufficient antistatic properties and suppresses plate-out, and a resin film containing a layer formed therefrom has excellent expandability. Therefore, a resin film containing a layer formed using the resin composition of the present invention can be suitably used as a base film for dicing tape, particularly as a base film for dicing tape used in producing small, thin-film semiconductor chips. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a conceptual diagram of the film-forming apparatus used in the examples. DETAILED DESCRIPTION OF THE INVENTION

[0010] As used herein, the term "resin" is used to include resin mixtures containing two or more resins, as well as resin compositions containing components other than resin. As used herein, the term "film" is used interchangeably with "sheet." As used herein, the terms "film" and "sheet" refer to materials that can be industrially wound into rolls. The term "plate" refers to materials that cannot be industrially wound into rolls. Furthermore, as used herein, laminating one layer and another layer in order includes both directly laminating the layers and laminating the layers with one or more additional layers, such as an anchor coat, interposed between them.

[0011] In this specification, the term "more than or equal to" in relation to a numerical range means a certain number or more than a certain number. For example, 20% or more means 20% or more than 20%. The term "less than or equal to" in relation to a numerical range means a certain number or less than a certain number. For example, 20% or less means 20% or less than 20%. Furthermore, the symbol "to" in relation to a numerical range means a certain number, more than a certain number and less than another certain number, or another certain number. Here, another certain number is a number greater than the certain number. For example, 10 to 90% means 10%, more than 10% and less than 90%, or 90%. Furthermore, the upper and lower limits of a numerical range can be arbitrarily combined, and embodiments incorporating such combinations can be interpreted. For example, from a statement regarding the numerical range of a certain characteristic such as "usually 10% or more, preferably 20% or more. On the other hand, it is usually 40% or less, preferably 30% or less," or "usually 10 to 40%, preferably 20 to 30%," it can be read that the numerical range of the certain characteristic is 10 to 40%, 20 to 30%, 10 to 30%, or 20 to 40% in one embodiment.

[0012] Other than in the examples, or where otherwise specified, all numerical values ​​used in the specification and claims should be understood to be modified by the term "about." Without attempting to limit the application of the doctrine of equivalents to the claims, each numerical value should be construed in light of the number of significant digits and by applying ordinary rounding techniques.

[0013] 1.Resin composition The resin composition of the present invention contains (A) an ethylene-based resin, (B) a propylene-based resin, and (C) a block copolymer of propylene and a polyhydric alcohol. Here, the component (B) propylene-based resin does not include a block copolymer of propylene and a polyhydric alcohol. Therefore, compounds corresponding to the component (C) block copolymer of propylene and a polyhydric alcohol are excluded from the scope of the component (B) propylene-based resin. In other words, compounds corresponding to the block copolymer of propylene and a polyhydric alcohol are component (C) but not component (B). Each component will be described below.

[0014] (A) Ethylene-based resin The component (A) ethylene-based resin is a resin primarily containing structural units derived from ethylene. Here, "primarily containing structural units derived from ethylene" means that the content of structural units derived from ethylene is usually 50% by mass or more, preferably 60% by mass or more, more preferably 70% by mass or more, and typically 75 to 100% by mass, based on the total mass of the ethylene-based resin. The component (A) ethylene-based resin functions to improve the expandability of the resin film.

[0015] Examples of the ethylene resin component (A) include low-density polyethylene, linear low-density polyethylene, very low-density polyethylene, medium-density polyethylene, and high-density polyethylene; ethylene-α-olefin copolymers such as ethylene-1-butene copolymer, ethylene-1-hexene copolymer, and ethylene-1-octene copolymer; ethylene-vinyl acetate copolymer; ethylene-unsaturated carboxylic acid ester copolymers such as ethylene-ethyl acrylate copolymer and ethylene-methyl methacrylate copolymer; ethylene-unsaturated carboxylic acid copolymers such as ethylene-acrylic acid copolymer and ethylene-methacrylic acid copolymer; ethylene-unsaturated carboxylic acid-unsaturated carboxylic acid ester copolymers such as ethylene-(meth)acrylic acid-(meth)acrylic acid alkyl ester copolymer; and ionomer resins in which the ethylene-unsaturated carboxylic acid copolymers or the ethylene-unsaturated carboxylic acid-unsaturated carboxylic acid ester copolymers are intermolecularly crosslinked with metal ions.

[0016] Examples of the metal ions used in the ionomer resin include lithium ions, sodium ions, potassium ions, rubidium ions, cesium ions, zinc ions, magnesium ions, and manganese ions. Among these metal ions, magnesium ions, and zinc ions are preferred, and sodium ions and zinc ions are more preferred.

[0017] When an ethylene-vinyl acetate copolymer, an ethylene-unsaturated carboxylic acid ester copolymer, an ethylene-unsaturated carboxylic acid copolymer, an ethylene-unsaturated carboxylic acid-unsaturated carboxylic acid ester copolymer, or an ionomer resin is used as the component (A) ethylene-based resin, the content of structural units derived from ethylene may be typically 98% by mass or less, preferably 96% by mass or less, and more preferably 94% by mass or less, based on the total mass of the ethylene-based resin, from the viewpoint of the expandability of the resin film. On the other hand, from the viewpoint of the blocking resistance of the resin film, this content may be typically 70% by mass or more, preferably 75% by mass or more, and more preferably 80% by mass or more.

[0018] When low-density polyethylene, linear low-density polyethylene, very low-density polyethylene, medium-density polyethylene, high-density polyethylene, or ethylene-α-olefin copolymer is used as the component (A) ethylene-based resin, the density (measured by the immersion method (ISO1183-1:2019) in accordance with JIS K6922-2:2018) is usually 950 kg / m from the viewpoint of the expandability of the resin film. 3 Less than or equal to 945 kg / m 3 Less than or equal to 940 kg / m 3 or less, more preferably 935 kg / m 3 Below 930 kg / m, most preferably 3 On the other hand, from the viewpoint of the blocking resistance of the resin film, this density is usually 880 kg / m 3 or more, preferably 890 kg / m 3More preferably, 900 kg / m 3 It may be more than that.

[0019] From the viewpoint of film formability, the melt mass flow rate of the component (A) ethylene resin at 190°C may be usually 0.1 to 20 g / 10 min, preferably 0.5 to 10 g / 10 min. The melt mass flow rate of the component (A) ethylene resin is measured in accordance with JIS K7210-1:2014 under conditions of a temperature of 190°C and a load of 21.18 N.

[0020] Among these, as the component (A) ethylene-based resin, from the viewpoint of suppressing plate-out, ethylene-unsaturated carboxylic acid copolymer, ethylene-unsaturated carboxylic acid-unsaturated carboxylic acid ester copolymer, ionomer resin of ethylene-unsaturated carboxylic acid copolymer, and ionomer resin of ethylene-unsaturated carboxylic acid-unsaturated carboxylic acid ester copolymer are preferred.

[0021] Without intending to be bound by theory, it is believed that these compounds share the common characteristic of having a carboxyl group in the molecule, and that the carboxyl group strongly interacts with the structural units derived from the polyhydric alcohol in the block copolymer of propylene and a polyhydric alcohol (component (C))) and with the metal ions contained in component (C), thereby suppressing plate-out of the block copolymer of propylene and a polyhydric alcohol (component (C)).

[0022] As the component (A) ethylene resin, one of these may be used alone or a mixture of two or more thereof. When a mixture of two or more types of ethylene resins (component (A)) is used, the properties of the mixture should be determined by measuring the properties of the mixture.

[0023] (B) Propylene-based resin The propylene-based resin (B) is a resin primarily containing structural units derived from propylene. Here, "primarily containing structural units derived from propylene" means that the content of structural units derived from propylene is usually 50% by mass or more, preferably 60% by mass or more, more preferably 70% by mass or more, and typically 75 to 100% by mass, based on the total mass of the propylene-based resin. As mentioned above, the component (B) propylene-based resin does not include a block copolymer of propylene and a polyhydric alcohol, and therefore, the component (B) propylene-based resin excludes compounds corresponding to the component (C) block copolymer of propylene and a polyhydric alcohol.

[0024] The propylene resin component (B) inhibits plate-out of the block copolymer of propylene and polyhydric alcohol component (C) and serves to enhance the antistatic effect of component (C). Without intending to be bound by theory, it is believed that the propylene resin component (B) exhibits these functions through the following mechanism.

[0025] In the case of a resin composition comprising component (A) an ethylene-based resin and component (C) a block copolymer of propylene and a polyhydric alcohol, i.e., without component (B) a propylene-based resin, if the amount of component (C) is small, the component (C) forms a morphology in which the island phases of component (C) are dispersed and floating in isolation within the sea phase of component (A), resulting in insufficient antistatic properties. To achieve sufficient antistatic properties, a large amount of component (C) must be blended so that the island phases of component (C) are close together and continuous, forming electrical paths. However, component (A) and component (C) are not sufficiently miscible or compatible, and blending a large amount of component (C) results in component (C) easily plating out.

[0026] When the propylene-based resin component (B) is added to the resin composition, i.e., in the case of a resin composition of the ethylene-based resin component (A), the propylene-based resin component (B), and the block copolymer of propylene and a polyhydric alcohol component (C), the segments of the component (C) that share a structure with the component (B), i.e., the propylene polymer segments of the component (C), are compatible with the component (B) to form an island phase or a eutectic. Therefore, even when a large amount of the component (C) is blended, plate-out of the component (C) is suppressed. On the other hand, from the viewpoint of forming electrical paths, the essential segments of component (C), i.e., the polyhydric alcohol polymer segments of component (C), are insufficiently miscible and compatible with component (B). Therefore, when component (B) and the propylene polymer segments of component (C) solidify / crystallize, they are excreted into the still-molten phase (the sea phase of component (A) when the crystallization temperature of component (A) is lower than that of components (B) and (C), or the amorphous or low-crystalline component phase of component (A) when the crystallization temperature of component (A) is higher than that of components (B) and (C). As a result, the polyhydric alcohol polymer segments of component (C) are present at a high concentration in the still-molten phase, and when the still-molten phase solidifies, adjacent, continuous island phases, i.e., electrical paths, are formed, thereby achieving sufficient antistatic properties.

[0027] Examples of the propylene-based resin component (B) include propylene homopolymers and copolymers (including block copolymers and random copolymers) of propylene with one or more α-olefins (e.g., ethylene, 1-butene, 1-hexene, and 1-octene).

[0028] Among these, the propylene-based resin component (B) is preferably a copolymer of propylene and an α-olefin from the viewpoint of miscibility and compatibility with the ethylene-based resin component (A).

[0029] The melting point of the propylene resin (component (B)) may be usually 120° C. or higher, preferably 125° C. or higher, and more preferably 130° C. or higher, from the viewpoint of heat resistance and solvent resistance of the resin film. On the other hand, the melting point may be usually 160° C. or lower, preferably 150° C. or lower, from the viewpoint of forming a eutectic with the propylene polymer segment of the block copolymer of propylene and a polyhydric alcohol (component (C)).

[0030] The fusion enthalpy of the propylene-based resin (B) may be generally 20 J / g or more, preferably 30 J / g or more, from the viewpoint of the heat resistance and solvent resistance of the resin film, while the fusion enthalpy may be generally 90 J / g or less, preferably 88 J / g or less, more preferably 80 J / g or less, even more preferably 70 J / g or less, and even more preferably 60 J / g or less, from the viewpoint of the expandability of the resin film.

[0031] In this specification, the melting point and melting enthalpy of the propylene-based resin (B) are calculated in accordance with JIS K7121-1987 using a differential scanning calorimeter (DSC) from a second melting curve (the melting curve measured during the final heating process) measured using a program that involves holding at 190°C for 5 minutes, cooling to -10°C at 10°C / min, holding at -10°C for 5 minutes, and then heating to 190°C at 10°C / min. The melting point is the peak-top temperature of the melting peak that appears in the second melting curve. When two or more melting peaks are observed, the melting point is determined to be the peak-top temperature of the melting peak with the greatest peak-top height. It should also be noted that the melting peak appearing in a DSC second melting curve usually has a gently extending, long base on both the high-temperature and low-temperature sides; and that the baseline should be drawn so that the line extending the high-temperature baseline to the low-temperature side coincides with the line extending the same low-temperature baseline to the high-temperature side, as shown in Figure 1 of JIS K7121-1987, Section 9. How to read DTA or DSC curves.

[0032] From the viewpoint of film-forming properties, the melt mass flow rate of the propylene resin (B) at 230°C may be preferably 0.1 to 20 g / 10 min, more preferably 0.5 to 15 g / 10 min, and even more preferably 1 to 10 g / 10 min. The melt mass flow rate of the propylene resin (B) is measured in accordance with JIS K7210-1:2014 at a temperature of 230°C and a load of 21.18 N. The melt mass flow rate of the propylene-based resin (component (B)) at 190°C can also be measured in accordance with JIS K7210-1:2014 under conditions of a temperature of 190°C and a load of 21.18N.

[0033] As the propylene-based resin component (B), one of these may be used alone or in combination with two or more thereof. When a mixture of two or more types of propylene resins (B) is used, it goes without saying that the properties of the mixture should be determined by measuring the properties of the mixture.

[0034] (C) Block copolymer of propylene and polyhydric alcohol The propylene-polyhydric alcohol block copolymer (C) is a block copolymer having a propylene polymer segment primarily containing propylene-derived structural units and a polyhydric alcohol polymer segment primarily containing polyhydric alcohol-derived structural units. "Mainly containing propylene-derived structural units" means that the content of propylene-derived structural units is typically 60% by mass or more, preferably 70% by mass or more, more preferably 80% by mass or more, even more preferably 90% by mass or more, and typically 95-100% by mass, based on the total mass of the propylene polymer segment. "Mainly containing polyhydric alcohol-derived structural units" means that the content of polyhydric alcohol-derived structural units is typically 60% by mass or more, preferably 70% by mass or more, more preferably 80% by mass or more, even more preferably 90% by mass or more, and typically 95-100% by mass, based on the total mass of the polyhydric alcohol polymer segment. The propylene-polyhydric alcohol block copolymer (C) exhibits antistatic properties.

[0035] The propylene polymer segment may be a propylene homopolymer segment, or may be a copolymer segment of propylene and one or more α-olefins (e.g., ethylene, 1-butene, 1-hexene, 1-octene, etc.).

[0036] Examples of polyhydric alcohols constituting the polyhydric alcohol polymer segment include aliphatic polyhydric alcohols such as ethylene glycol, diethylene glycol, neopentyl glycol, polyethylene glycol, 1,2-propanediol, 1,3-propanediol (trimethylene glycol), polypropylene glycol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol (tetramethylene glycol), 1,5-pentanediol, 1,6-hexanediol, neopentyl glycol, decamethylene glycol, 3-methyl-1,5-pentanediol, 2-methyl-1,3-propanediol, 1,2-cyclohexanediol, 1,4-cyclohexanediol, 1,4-cyclohexanedimethanol, 2,2,4,4'-tetramethyl-1,3-cyclobutanediol, glycerin, and trimethylolpropane. Among these, the polyhydric alcohol constituting the polyhydric alcohol polymer segment is preferably ethylene glycol, diethylene glycol, polyethylene glycol, 1,2-propanediol, 1,3-propanediol (trimethylene glycol), and polypropylene glycol, and more preferably ethylene glycol, diethylene glycol, and polyethylene glycol, from the viewpoint of forming a larger number of ether bonds relative to the number of carbon atoms and improving antistatic properties. The polyhydric alcohol polymer segment may be a polymer segment consisting only of structural units derived from a polyhydric alcohol, or may be a copolymer segment of a polyhydric alcohol and one or more copolymerizable monomers. Examples of the monomer copolymerizable with the polyhydric alcohol include compounds having two or more carboxyl groups in one molecule, such as aliphatic dicarboxylic acids, including oxalic acid, succinic acid, adipic acid, suberic acid, and sebacic acid, and compounds having two or more isocyanate groups in one molecule, such as aliphatic diisocyanates, including hexamethylene diisocyanate.

[0037] The amount of propylene-derived structural units in the block copolymer of propylene and polyhydric alcohol (component (C)) may be typically 30% by mass or more, preferably 40% by mass or more, and more preferably 50% by mass or more, from the viewpoint of suppressing plate-out. Meanwhile, the amount of propylene-derived structural units may be typically 90% by mass or less, preferably 80% by mass or less, and more preferably 70% by mass or less, from the viewpoint of antistatic properties. Meanwhile, the amount of polyhydric alcohol-derived structural units in the block copolymer of propylene and polyhydric alcohol (component (C))) may be typically 70% by mass or less, preferably 60% by mass or less, and more preferably 50% by mass or more, from the viewpoint of suppressing plate-out. Meanwhile, the amount of polyhydric alcohol-derived structural units may be typically 10% by mass or more, preferably 20% by mass or more, and more preferably 30% by mass or more, from the viewpoint of antistatic properties. Here, the sum of the amount of propylene-derived structural units and the amount of polyhydric alcohol-derived structural units is 100% by mass.

[0038] The sum of the amount of structural units derived from propylene and the amount of structural units derived from polyhydric alcohol in the block copolymer of propylene and polyhydric alcohol (component (C))) may be generally 80% by mass or more, preferably 90% by mass or more, and typically 95 to 100% by mass, where the total amount of each structural unit in component (C) is 100% by mass.

[0039] The component (C), a block copolymer of propylene and a polyhydric alcohol, may be doped with metal ions, which can improve antistatic properties.

[0040] Examples of the metal ion include lithium ion, cesium ion, rubidium ion, potassium ion, barium ion, strontium ion, calcium ion, and sodium ion. Of these, lithium ion is preferred as the metal ion from the viewpoint of improving antistatic properties.

[0041] The content of the metal ions in the block copolymer of propylene and polyhydric alcohol (component (C)) may be generally 100 ppm or more, preferably 150 ppm or more, more preferably 300 ppm or more, and even more preferably 500 ppm or more from the viewpoint of improving antistatic properties, while the content of the metal ions may be generally 2000 ppm or less, preferably 1500 ppm or less, and more preferably 1000 ppm or less from the viewpoint of suppressing plate-out.

[0042] In this specification, the content of the metal ions in the component (C), a block copolymer of propylene and a polyhydric alcohol, is measured by atomic absorption spectrometry. The measurement sample is prepared by ashing (wet decomposition) the sample using a microwave device with a mixed acid of nitric acid and hydrochloric acid (volume ratio 8:2), adding an aqueous hydrochloric acid solution, filtering, and adjusting the filtrate to volume with purified water. At this time (when adjusting the filtrate to volume with purified water), yttrium is added as an internal standard.

[0043] The melting point of the propylene polymer segment of the block copolymer of propylene and polyhydric alcohol (component (C)) may be usually (Tm-30) to (Tm+30)°C, preferably (Tm-20) to (Tm+20)°C, and more preferably (Tm-10) to (Tm+10)°C, from the viewpoint of forming a eutectic with the propylene resin (component (B)) and suppressing plate-out, where Tm is the melting point (unit: °C) of the propylene resin (component (B)).

[0044] In this specification, the melting point of the component (C) propylene and polyhydric alcohol block copolymer is calculated from a second melting curve (a melting curve measured during the final heating process) measured using a differential scanning calorimeter (DSC) in accordance with JIS K7121-1987, using a program that involves holding at 190°C for 5 minutes, cooling to -10°C at 10°C / min, holding at -10°C for 5 minutes, and then heating to 190°C at 10°C / min. The melting point of the propylene polymer segment is the peak-top temperature of the melting peak appearing in the temperature range of 100 to 165°C on the second melting curve. When two or more melting peaks are observed, the melting point is determined to be the peak-top temperature of the melting peak with the greatest peak-top height. The melting point of the polyhydric alcohol polymer segment varies depending on its composition, but in the case of a polyethylene glycol segment, for example, it is the peak-top temperature of the melting peak appearing in the temperature range of 20 to 60°C on the second melting curve. When two or more melting peaks are observed, the peak top temperature of the melting peak with the greatest peak top height is similarly taken as the melting point. It should also be noted that the melting peak appearing in a DSC second melting curve usually has a gently extending, long base on both the high-temperature and low-temperature sides; and that the baseline should be drawn so that the line extending the high-temperature baseline to the low-temperature side coincides with the line extending the same low-temperature baseline to the high-temperature side, as shown in Figure 1 of JIS K7121-1987, Section 9. How to read DTA or DSC curves.

[0045] From the viewpoint of film-forming properties, the melt mass flow rate of the component (C) block copolymer of propylene and polyhydric alcohol at 190°C may be preferably 0.1 to 20 g / 10 min, more preferably 0.5 to 15 g / 10 min, and even more preferably 1 to 10 g / 10 min. The melt mass flow rate of the component (C) block copolymer of propylene and polyhydric alcohol is measured in accordance with JIS K7210-1:2014 under conditions of a temperature of 190°C and a load of 21.18 N.

[0046] As the component (C), a block copolymer of propylene and a polyhydric alcohol, one of these or a mixture of two or more thereof can be used. When a mixture of two or more types of component (C) is used as the block copolymer of propylene and a polyhydric alcohol, the properties of the mixture should be determined by measuring the properties of the mixture.

[0047] The amount of the ethylene resin (A) may be usually 99 parts by mass or less, preferably 95 parts by mass or less, and more preferably 92 parts by mass or less, from the viewpoint of antistatic properties and plate-out suppression, where the sum of the amounts of the ethylene resin (A) and the propylene resin (B) is taken as 100 parts by mass. On the other hand, from the viewpoint of the expandability of the resin film, this amount may be usually 20 parts by mass or more, preferably 35 parts by mass or more, more preferably 45 parts by mass or more, and even more preferably 55 parts by mass or more. In one embodiment, the amount of the ethylene-based resin component (A) is typically 20 to 99 parts by mass, preferably 20 to 95 parts by mass, 20 to 92 parts by mass, 35 to 99 parts by mass, 35 to 95 parts by mass, 35 to 92 parts by mass, 45 to 99 parts by mass, 45 to 95 parts by mass, 45 to 92 parts by mass, 55 to 99 parts by mass, 55 to 95 parts by mass, or 55 to 92 parts by mass, where the sum of the amount of the ethylene-based resin component (A) and the amount of the propylene-based resin component (B) is 100 parts by mass.

[0048] The amount of the propylene-based resin (B) may be usually 1 part by mass or more, preferably 5 parts by mass or more, and more preferably 8 parts by mass or more, from the viewpoint of antistatic properties and plate-out suppression, where the sum of the amounts of the ethylene-based resin (A) and the propylene-based resin (B) is taken as 100 parts by mass. On the other hand, from the viewpoint of the expandability of the resin film, this amount may be usually 80 parts by mass or less, preferably 65 parts by mass or less, more preferably 55 parts by mass or less, and even more preferably 45 parts by mass or less. In one embodiment, the amount of the propylene-based resin component (B) is typically 1 part by mass or more and 80 parts by mass or less, preferably 1 part by mass or more and 65 parts by mass or less, 1 part by mass or more and 55 parts by mass or less, 1 part by mass or more and 45 parts by mass or less, 5 parts by mass or more and 80 parts by mass or less, 5 parts by mass or more and 65 parts by mass or less, 5 parts by mass or more and 55 parts by mass or less, 5 parts by mass or more and 45 parts by mass or less, 8 parts by mass or more and 80 parts by mass or less, 8 parts by mass or more and 65 parts by mass or less, 8 parts by mass or more and 55 parts by mass or less, or 8 parts by mass or more and 45 parts by mass, where the sum of the amount of the ethylene-based resin component (A) and the amount of the propylene-based resin component (B) is 100 parts by mass.

[0049] The blending amount of the block copolymer of propylene and polyhydric alcohol (Component (C)) may be usually 1 part by mass or more, preferably 5 parts by mass or more, more preferably 10 parts by mass or more, and even more preferably 15 parts by mass or more, per 100 parts by mass of the sum of the blending amount of the ethylene resin (Component (A)) and the propylene resin (Component (B)), while from the viewpoint of suppressing plate-out, it may be usually 39 parts by mass or less, preferably 35 parts by mass or less, more preferably 32 parts by mass or less, and even more preferably 29 parts by mass or less. In one embodiment, the amount of the block copolymer of propylene and polyhydric alcohol (C) is typically 1 part by mass or more and 39 parts by mass or less, preferably 1 part by mass or more and 35 parts by mass or less, 1 part by mass or more and 32 parts by mass or less, 1 part by mass or more and 29 parts by mass or less, 5 parts by mass or more and 39 parts by mass or less, 5 parts by mass or more and 35 parts by mass or less, 5 parts by mass or more and 32 parts by mass or less, 5 parts by mass or more and 29 parts by mass or less, 10 parts by mass or more and 39 parts by mass or less, 10 parts by mass or more and 35 parts by mass or less, 10 parts by mass or more and 32 parts by mass or less, 10 parts by mass or more and 29 parts by mass or less, 15 parts by mass or more and 39 parts by mass or less, 15 parts by mass or more and 35 parts by mass or less, 15 parts by mass or more and 32 parts by mass or less, or 15 parts by mass or more and 29 parts by mass or less.

[0050] The mass ratio of the amount of the propylene resin (Component (B)) to the amount of the block copolymer of propylene and polyhydric alcohol (Component (C)) (Amount of Component (B) / Amount of Component (C)) is preferably 0.4 or more, more preferably 0.6 or more, and more preferably 0.8 or more, from the viewpoint of suppressing plate-out. On the other hand, this mass ratio is preferably 10 or less, more preferably 6 or less, from the viewpoint of forming a eutectic between Component (B) and the propylene polymer segment of Component (C) and suppressing plate-out, even when there is a large difference between their melting points.

[0051] The melt mass flow rate of the component (A) ethylene resin at 190° C. may be lower, preferably at most half, the melt mass flow rate of the component (C) block copolymer of propylene and polyhydric alcohol at 190° C. When the melt mass flow rates of both resins satisfy the above relationship, the polyhydric alcohol polymer segments of the component (C) become elongated island phases upon receiving shear stress, facilitating the formation of electrical paths, and enabling the development of sufficient antistatic properties.

[0052] 2. Resin film The resin film of the present invention is a resin film comprising at least one layer formed from the resin composition of the present invention. The resin film of the present invention typically comprises at least one layer formed from the resin composition of the present invention, with the layer forming at least one surface of the resin film. The resin film of the present invention may be a monolayer film or a multilayer film. In one embodiment, the resin film of the present invention may be a monolayer film. In another embodiment, the resin film of the present invention may be a multilayer film in which both outer layers are formed using virgin materials from the resin composition of the present invention, and the intermediate layer is formed using a mixture of virgin materials from the resin composition of the present invention and recycled materials such as film selvages (cut portions on both ends that exceed the set width range generated during film production).

[0053] The method for producing the resin film of the present invention is not particularly limited, and known film production methods can be used. Examples of the film production method include a method for producing a film using a calender roll rolling film production device equipped with a calender roll rolling processing machine and a take-up device; a method for producing a film using a T-die film production device equipped with an extruder, a T-die and a take-up device; and a method for producing a film using an inflation film production device equipped with an extruder, a circular die, an inflation device and a take-up device having a nip mechanism.

[0054] Examples of the calender roll rolling machine include an upright three-roll machine, an upright four-roll machine, an L-shaped four-roll machine, an inverted L-shaped four-roll machine, and a Z-roll machine. Examples of the extruder include a single-screw extruder, a co-rotating twin-screw extruder, and a counter-rotating twin-screw extruder. Examples of the T-die include a manifold die, a fishtail die, and a coat hanger die.

[0055] The thickness of the resin film of the present invention is not particularly limited and can be appropriately selected taking into consideration the intended use of the resin film. When the resin film of the present invention is used as a substrate film for a dicing tape, its thickness may be usually 30 to 300 μm, preferably 50 to 200 μm, and more preferably 70 to 150 μm. The thickness here refers to the thickness of the entire resin film including at least one layer formed from the resin composition of the present invention (when the film consists of multiple layers, the total thickness of those layers).

[0056] The surface resistivity of the resin film of the present invention is usually 1×10 6 ~1×10 11 Ω / □, preferably 1×10 7 ~1×10 10 Ω / □, more preferably 1×10 8 ~1×10 10 Ω / □, and even more preferably 1×10 8 ~1×10 9When the resin film of the present invention has a surface resistivity in the above range, it can be suitably used as a substrate film for an antistatic dicing tape.

[0057] In this specification, surface resistivity is measured in accordance with 5.13 Resistivity and 5.13.2 Laminated Plates of JIS K6911:1995, except that the test specimen is pretreated by leaving it in an environment of 25°C and 50% relative humidity for 24 hours and the resistivity is measured in an environment of 25°C and 50% relative humidity. A probe is attached to the test specimen with a load of 30 N, a voltage of 100 V is applied, and the surface resistivity (unit: Ω / □) is measured 30 seconds later. The test specimen is a square film piece with sides of 10 cm taken from a resin film (typically a base film for dicing tape).

[0058] The 5% strain tensile stress in the machine direction of the resin film of the present invention may be usually 15 MPa or less (more than 0 MPa), preferably 12 MPa or less (more than 0 MPa), more preferably 2 to 10 MPa, and even more preferably 3 to 8 MPa. The 10% strain tensile stress in the machine direction of the resin film of the present invention may be usually 20 MPa or less (more than 0 MPa), preferably 18 MPa or less (more than 0 MPa), more preferably 2 to 15 MPa, and even more preferably 4 to 12 MPa. The 20% strain tensile stress in the machine direction of the resin film of the present invention may be usually 20 MPa or less (more than 0 MPa), preferably 18 MPa or less (more than 0 MPa), more preferably 3 to 15 MPa, and even more preferably 6 to 12 MPa. The 100% strain tensile stress in the machine direction of the resin film of the present invention may be usually 25 MPa or less (more than 0 MPa), preferably 20 MPa or less (more than 0 MPa), more preferably 4 to 18 MPa, and even more preferably 8 to 15 MPa. When the resin film of the present invention has a strain tensile stress within the above range, it can be suitably used as a substrate film for an antistatic dicing tape having excellent expandability.

[0059] The machine direction strain tensile stresses of the resin film of the present invention may preferably be such that the 10% strain tensile stress is greater than the 5% strain tensile stress, the 20% strain tensile stress is greater than the 10% strain tensile stress, and the 100% strain tensile stress is greater than the 20% strain tensile stress. When the machine direction strain tensile stresses of the resin film of the present invention satisfy the above-mentioned relationship, necking is strongly suppressed, and the film can be suitably used as a base film for antistatic dicing tape with excellent expandability. Here, "necking" refers to the occurrence of partial elongation due to poor force propagation when the film is stretched.

[0060] Here, each strain tensile stress is measured according to the following test (iv) tensile test.

[0061] 3. Dicing tape The dicing tape of the present invention is a dicing tape using the resin film of the present invention as a base film, and is usually produced by forming a pressure-sensitive adhesive layer directly or via an anchor coat on one side of the resin film of the present invention, and then slitting the resulting tape to a desired width.

[0062] The adhesive for forming the adhesive layer is not particularly limited, and any adhesive can be used. Examples of adhesives for forming the adhesive layer include acrylic adhesives such as poly(meth)acrylic acid alkyl esters and copolymers of (meth)acrylic acid alkyl esters with other monomers, rubber adhesives such as natural rubber and butyl-isoprene rubber, polyurethane adhesives, polyester adhesives, polystyrene adhesives, and silicone adhesives.

[0063] The adhesive for forming the adhesive layer is preferably an adhesive with excellent transparency, from the viewpoint of ensuring the transparency required for dicing tape, for example, sufficient visibility during laser marking. Here, "an adhesive with excellent transparency" refers to an adhesive with a visible light transmittance of typically 50% or more, preferably 70% or more, more preferably 80% or more, and even more preferably 85% or more. Visible light transmittance can be calculated as the ratio of the integrated area of ​​the transmission spectrum of the adhesive at wavelengths of 380 to 780 nanometers, measured using a Shimadzu Corporation "Solid Spec-3700" (trade name) spectrophotometer and a quartz cell with an optical path length of 10 mm, to the integrated area of ​​the transmission spectrum assuming a transmittance of 100% over the entire wavelength range of 380 to 780 nanometers.

[0064] As the adhesive for forming the adhesive layer, an adhesive whose adhesive strength can be reduced by heat curing or active energy ray curing is also preferred. The reduced adhesive strength allows the dicing tape to be easily and cleanly peeled off from the workpiece (processed object) without leaving any adhesive residue. Furthermore, the amount of static electricity generated when peeling the dicing tape from the workpiece can be reduced. Examples of adhesives whose adhesive strength can be reduced by heat curing or active energy ray curing include adhesives having two or more reactive functional groups per molecule (e.g., amino groups, vinyl groups, epoxy groups, methacryloxy groups, acryloxy groups, isocyanate groups, etc.); and adhesive compositions containing such adhesives and at least one of an isocyanate-based curing agent, a photopolymerization initiator, and an organic peroxide.

[0065] As the adhesive for forming the adhesive layer, an adhesive having antistatic properties is also preferred. The surface resistivity of the adhesive layer formed using the antistatic adhesive is usually 1×10 6 ~1×10 11 Ω / □, preferably 1×10 7 ~1×10 10 Ω / □, more preferably 1×10 8~1×10 10 Ω / □, and even more preferably 1×10 8 ~1×10 9 The electrical resistance may be Ω / □. Examples of the antistatic pressure-sensitive adhesive include pressure-sensitive adhesives disclosed in JP 2007-191532 A, JP 2008-007702 A, JP 2009-242745 A, and WO 2015 / 030186 A.

[0066] As the adhesive for forming the adhesive layer, one of these or a mixture of two or more thereof can be used.

[0067] The thickness of the pressure-sensitive adhesive layer is not particularly limited and can be any thickness. The thickness of the pressure-sensitive adhesive layer may be generally about 1 to 25 μm, and preferably about 5 to 20 μm. [Example]

[0068] The present invention will be described below with reference to examples, but the present invention is not limited to these examples.

[0069] Measurement method (i) Surface resistivity The test specimens were pretreated by leaving them in an environment at 25°C and 50% relative humidity for 24 hours, and the resistivity measurements were performed in an environment at 25°C and 50% relative humidity, in accordance with JIS K6911:1995, sections 5.13 Resistivity and 5.13.2 Laminates. A resistivity meter "Hiresta-UP MCP-HT450 (trade name)" and a dual ring probe "MCP-JB03 (trade name)" manufactured by Nitto Seiko Analytech Co., Ltd. were used. The probe was crimped to the test specimen with a load of 30 N, a voltage of 100 V was applied, and the surface resistivity (unit: Ω / □) was measured 30 seconds later. A square film piece with sides of 10 cm was taken from the dicing tape substrate film. Note that the notation "1.0E+10" in the table indicates a surface resistivity of 1.0 x 10 10 Ω / □. Also, >1.0E+11 means that the surface resistivity is 1.0×10 11 This means that it exceeded Ω / □.

[0070] (ii) Plate-out index (ΔG) The film-making apparatus used was the one shown in the conceptual diagram of Figure 1 (equipped with a 40 mm diameter extruder 1, a 600 mm wide T-die 2 at the resin outlet, and a take-up device with a nipping mechanism between a 150 mm diameter smooth roll (mirror-finish metal roll) 4 and a 250 mm diameter textured roll (matt-finish rubber roll) 5). Measurements were performed in accordance with JIS Z8741-1997 using a spectrophotometer "CM-600d" (trade name) manufactured by Konica Minolta, Inc., equipped with a target mask "CM-A180" (trade name) that came with the spectrophotometer, except that the 8-degree specular gloss (G0) of the smooth roll surface of the film-making apparatus (a location 5 cm toward the center in the width direction from where the right edge of the molten film in the width direction contacts the smooth roll surface; hereinafter referred to as the "predetermined location") was used to measure the specular gloss of the curved surface, and the incident and reflection angles of light were set to 8 degrees. At this time, a jig was used to fit the smooth roll and the color difference meter and to ensure that the angle of incidence and reflection of light were 8 degrees. Next, 3 kg of the resin composition was continuously extruded from the T-die 2 as a molten film 3, and the extruded molten film 3 was fed between the rotating smooth roll 4 and the rotating textured roll 5, and pressed between the smooth roll 4 and the textured roll 5. The pressed molten film 3 was wrapped around the smooth roll 4 and sent to the next rotating roll 6, producing a film 7 with a thickness of 100 μm. At this time, the resin temperature at the T-die outlet was 210 ° C., the surface temperature of the smooth roll 4 was 25 ° C., the temperature of the cooling water flowing through the textured roll 5 was 25 ° C., and the take-up speed was 4 m / min. After film production (after all 3 kg of the resin composition had been extruded from the T-die), the 8-degree specular gloss value (G1) of a predetermined location on the smooth roll surface of the film-forming apparatus was measured in the same manner as the 8-degree specular gloss value (G0). The plate-out index (ΔG) was calculated from the 8-degree specular gloss values ​​of the smooth roll surface before and after film formation using the following formula (1). ΔG=(1-G1 / G0)×100 (1)

[0071] (iii) Plate-out condition (visual observation) The state of the smooth roll surface was visually observed, and the state of plate-out was judged according to the following criteria. A: Plate-out is sufficiently suppressed. B: Plate-out is almost completely suppressed. C: Plate-out is observed. D: Significant plate-out is observed.

[0072] When the plate-out condition (visual observation) of the above test (iii) was ranked A, ΔG was generally 10% or less. When it was ranked B, ΔG was generally more than 10% to 20%. When it was ranked C, ΔG was generally more than 20% to 30%. When it was ranked D, ΔG was generally more than 30%.

[0073] (iv) Tensile test In accordance with JIS K7127:1999, a tensile testing machine "Autograph AGS-1kNG" (product name) manufactured by Shimadzu Corporation was used to punch out samples from the film into the shape of Type 5 test pieces of the above standard (Figure 2 of the JIS standard) with the machine direction of the film as the tensile direction. Tensile tests were conducted at a tensile speed of 200 mm / min and a temperature of 23°C, and a stress-strain curve in the machine direction (hereinafter referred to as the "SS curve") was obtained. From the obtained SS curves in the machine direction, the 5% strain tensile stress in the machine direction (referred to as "5% MD" in the table), the 10% strain tensile stress in the machine direction (referred to as "10% MD" in the table), the 20% strain tensile stress in the machine direction (referred to as "20% MD" in the table), and the 100% strain tensile stress in the machine direction (referred to as "100% MD" in the table) were calculated according to Section 10.1 of JIS K7161-1:2014. The units of these strain tensile stresses are all MPa.

[0074] Raw materials used (A) Ethylene-based resin (A-1) "Himilan 1855" (trade name), an ionomer resin crosslinked with zinc ions from Mitsui Dow Polychemicals Co., Ltd., with a melt mass flow rate (190°C, 21.18N) of 1.0 g / 10 min and a melting point of 83°C. According to JP 2013-098443 A, this is an ionomer resin in which an ethylene-methacrylic acid-ethyl methacrylate copolymer is crosslinked with zinc ions. The content of structural units derived from ethylene is 80% by mass, the content of structural units derived from methacrylic acid is 10% by mass, and the content of structural units derived from ethyl methacrylate is 10% by mass. (A-2) "Himilan 1652" (trade name), an ionomer resin crosslinked with zinc ions from Mitsui Dow Polychemicals Co., Ltd., with a melt mass flow rate (190°C, 21.18N) of 5.5 g / 10 min and a melting point of 96°C. According to JP 2008-052011 A, this is an ionomer resin in which an ethylene-methacrylic acid copolymer is crosslinked with zinc ions. The content of structural units derived from methacrylic acid is 16% by mass (the content of structural units derived from ethylene is 84% ​​by mass). (A-3) "Himilan 1707" (trade name), an ionomer resin crosslinked with sodium ions, manufactured by Mitsui Dow Polychemicals Co., Ltd., with a melt mass flow rate (190°C, 21.18N) of 0.9 g / 10 min and a melting point of 86°C. (A-4) Ethylene-methacrylic acid copolymer "Nucrel N0903HC" (trade name) from Dow Mitsui Polychemicals Co., Ltd., melt mass flow rate (190°C, 21.18N) 2.5 g / 10 min, content of structural units derived from methacrylic acid 9% by mass (content of structural units derived from ethylene 91% by mass), melting point 98°C. (A-5) Tosoh Corporation's ethylene-vinyl acetate copolymer "Ultrathene 515" (trade name), melt mass flow rate 2.5 g / 10 min, content of structural units derived from vinyl acetate 6% by mass (content of structural units derived from ethylene 94% by mass), melting point 100°C. (A-6) Tosoh Corporation's low-density polyethylene "Petrothene 339" (trade name), melt mass flow rate (190°C, 21.18N) 3.0g / 10min, density 924kg / m 3 , melting point 109℃. (A-7) High-density polyethylene "Hi-Zex 3300F" (trade name) from Prime Polymer Co., Ltd., melt mass-flow rate (190°C, 21.18N) 1.1g / 10min, density 949kg / m 3 , melting point 131℃.

[0075] (B) Propylene-based resin (B-1) Japan Polypropylene Corporation's propylene-ethylene copolymer "Wellnex RFX4V" (trade name), melt mass flow rate (230°C, 21.18N) 6.0 g / 10 min, melt mass flow rate (190°C, 21.18N) 3.0 g / 10 min, melting point 131°C, melting enthalpy 55 J / g. According to JP 2017-100357 A, this is a propylene-ethylene block copolymer. The content of ethylene-derived structural units is 29 mol% (calculated as 21% by mass) (the content of propylene-derived structural units is 71 mol% (calculated as 79% by mass)). (B-2) Sumitomo Chemical Co., Ltd.'s propylene-1-butene copolymer "Tafthren T3732" (trade name), melt mass flow rate (230°C, 21.18N) 3g / 10 min, melt mass flow rate (190°C, 21.18N) 1.3g / 10 min, melting point 129°C, melting enthalpy 32J / g. According to JP 2005-280173 A, it is a propylene-1-butene random copolymer. The content of structural units derived from 1-butene is 5% by mass (the content of structural units derived from propylene is 95% by mass). (B-3) Prime Polymer Co., Ltd.'s propylene-ethylene random copolymer "F-730NV" (trade name), melt mass-flow rate (230°C, 21.18 N) 7.0 g / 10 min, melt mass-flow rate (190°C, 21.18 N) 3.0 g / 10 min, melting point 139°C, fusion enthalpy 88 J / g, content of structural units derived from ethylene 3.4% by mass (content of structural units derived from propylene 96.6% by mass).

[0076] (C) Block copolymer of propylene and polyhydric alcohol: (C-1) Block copolymer having a propylene polymer segment and a polyethylene glycol segment, "Pelectron PVH" (trade name), melt mass flow rate (190°C, 21.18N) 8g / 10min, content of structural units derived from propylene 60% by mass, content of structural units derived from polyethylene glycol 40% by mass, melting point of propylene polymer segment 134°C, melting point of polyethylene glycol segment 34°C, contains 770ppm of lithium ions. (C-2) Block copolymer having a propylene polymer segment and a polyethylene glycol segment, "Pelectron LMP-FS" (trade name), melt mass flow rate (190°C, 21.18N) 15g / 10min, content of structural units derived from propylene 56% by mass, content of structural units derived from polyethylene glycol 44% by mass, melting point of propylene polymer segment 113°C, melting point of polyethylene glycol segment 34°C, contains 180ppm of lithium ions. (C-3) Block copolymer having a propylene polymer segment and a polyethylene glycol segment, "Pelectron PVL" (trade name), melt mass flow rate (190°C, 21.18N) 15g / 10min, content of structural units derived from propylene 59% by mass, content of structural units derived from polyethylene glycol 41% by mass, melting point of propylene polymer segment 132°C, melting point of polyethylene glycol segment 33°C, contains 180ppm of lithium ions.

[0077] Example 1 A resin composition containing 80 parts by mass of the component (A-1), 20 parts by mass of the component (B-1), and 20 parts by mass of the component (C-1) was used in a film-forming apparatus (including an extruder 1, a T-die 2, and a take-up device having a nipping mechanism between a smooth roll (a mirror-finished metal roll) 4 and a textured rubber roll (a matte rubber roll) 5) as shown in the conceptual diagram of FIG. 1 . The resin composition was continuously extruded from the T-die 2 as a molten film 3. The extruded molten film 3 was then fed between the rotating smooth roll 4 and the rotating textured roll 5 and pressed between the smooth roll 4 and the textured roll 5. The pressed molten film 3 was then wrapped around the smooth roll 4 and sent to the next rotating roll 6, producing a 100 μm-thick film 7. The resin temperature at the T-die outlet was 210°C, the surface temperature of the smooth roll 4 was 25°C, the temperature of the cooling water flowing through the textured roll 5 was 25°C, and the take-up speed was 4 m / min. The above tests (i) to (iv) were carried out, and the results are shown in Table 1.

[0078] Examples 2-25 A film was produced in the same manner as in Example 1, except that the formulation of the resin composition was changed to one shown in any one of Tables 1 to 3. The above tests (i) to (iv) were carried out. The results are shown in any one of Tables 1 to 3.

[0079] [Table 1]

[0080] [Table 2]

[0081] [Table 3]

[0082] It has been found that the resin composition of the present invention suppresses plate-out, and that resin films formed using the composition have sufficient antistatic properties. It has been found that the preferred resin composition of the present invention suppresses plate-out, and that resin films formed using the composition have sufficient antistatic properties and excellent expandability. Therefore, it has been considered that resin films formed using the resin composition of the present invention are suitable as substrate films for antistatic dicing tapes.

[0083] It will be obvious to those skilled in the art that the resin composition of the present invention has the above-mentioned desirable properties and can therefore be suitably used as a material for injection molded products, extrusion molded products, and the like. Furthermore, since the resin film formed using the resin composition of the present invention has the preferred properties as described above, it will be obvious to those skilled in the art that it can also be suitably used as a film or tape for semiconductor production other than dicing tape, for example, a backgrind tape (used to protect the circuit surface in the process of thinly grinding a wafer) or a die attach film (used to adhesively stack and mount cut wafer chips). [Explanation of symbols]

[0084] 1: Extruder 2:T die 3: Melting film 4: Smoothing roll 5: Shiborol 6: Rotating roll 7: Film

Claims

1. (A) 20 to 99 parts by mass of an ethylene-based resin, (B) 80 to 1 parts by mass of a copolymer of propylene and an α-olefin, and (C) 1 to 39 parts by mass of a block copolymer of propylene and a polyhydric alcohol Including; where: The component (A) ethylene-based resin is an ethylene-based resin having a carboxyl group in the molecule, The sum of the blending amount of the component (A) ethylene resin and the blending amount of the component (B) propylene and α-olefin copolymer is 100 parts by mass; The component (B) copolymer of propylene and α-olefin does not include a block copolymer of propylene and a polyhydric alcohol. Resin composition.

2. The resin composition according to claim 1, wherein the mass ratio of the blending amount of the component (B) propylene and α-olefin copolymer to the blending amount of the component (C) propylene and polyhydric alcohol block copolymer is 0.4 or more.

3. the melt mass flow rate of the component (A) ethylene-based resin is lower than the melt mass flow rate of the component (C) block copolymer of propylene and polyhydric alcohol; Here, the melt mass flow rate of the component (A) ethylene resin and the melt mass flow rate of the component (C) propylene and polyhydric alcohol block copolymer are measured in accordance with JIS K7210-1:2014 under conditions of a temperature of 190°C and a load of 21.18 N. The resin composition according to claim 1 or 2.

4. the melting point of the propylene polymer segment of the component (C) propylene and polyhydric alcohol block copolymer is (Tm-30) to (Tm+30)°C; Here, Tm is the melting point (unit: °C) of the component (B) propylene and α-olefin copolymer. The resin composition according to any one of claims 1 to 3.

5. A resin composition described in any one of claims 1 to 4, wherein the component (A) ethylene-based resin comprises at least one selected from the group consisting of ethylene-unsaturated carboxylic acid copolymers, ethylene-unsaturated carboxylic acid-unsaturated carboxylic acid ester copolymers, ionomer resins of ethylene-unsaturated carboxylic acid copolymers, and ionomer resins of ethylene-unsaturated carboxylic acid-unsaturated carboxylic acid ester copolymers.

6. The resin composition according to any one of claims 1 to 5, which is used for a base film of a dicing tape.

7. A substrate film for dicing tape comprising at least one layer formed from the resin composition described in any one of claims 1 to 6.

8. A dicing tape having a substrate film for dicing tape which comprises at least one layer formed from the resin composition according to any one of claims 1 to 6.

9. A resin film comprising at least one layer formed from the resin composition described in any one of claims 1 to 5.

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