Cover Tape and Electronic Component Package Containing the Same

Abstract

Provided is an environmentally considerate cover tape containing a certain amount of biomass-derived resin, which can achieve mechanical properties equivalent to those of conventional cover tapes, and an electronic component package containing the same. A cover tape, wherein the cover tape has a base material layer, a support layer, and a heat seal layer laminated in this order, the support layer contains a linear low-density polyolefin resin (A) and a polyolefin resin (B) other than the resin (A), and the ratio of the biomass-derived linear low-density polyolefin resin (a1) to the total mass of the resin (A) is 0 to 50% by mass, and the ratio of the biomass-derived polyolefin resin (b1) to the total mass of the resin (B) is 50 to 100% by mass.

Description

Technical Field

[0001] The present invention relates to a cover tape and an electronic component package including the same.

Background Art

[0002] With the miniaturization of electronic devices, the electronic components used are also being miniaturized and enhanced in performance. At the same time, in the assembly process of electronic devices, electronic components are automatically mounted on a printed circuit board. Such chip-type surface mount electronic components are stored in a carrier tape in which storage pockets thermally formed according to the shape of the electronic components are continuously formed. After storing the electronic components in each storage pocket, a cover tape is overlaid on the upper surface of the carrier tape as a lid material, and both ends of the cover tape are continuously heat-sealed in the length direction with a heated seal coat to form an electronic component package.

[0003] In recent years, with the increasing demand for building a recycling-based society, in the material field as well as in the energy field, it is desired to move away from fossil fuels, and the use of biomass has attracted attention. Biomass is an organic compound synthesized from carbon dioxide and water, and is a so-called "carbon-neutral" renewable energy. These days, the practical application of biomass plastics (resins derived from biomass) using such biomass as a raw material has been rapidly progressing, and in the cover tape and carrier tape for electronic component packages, replacement of petroleum-derived resins with biomass-derived resins is being studied. For example, Patent Document 1 proposes a cover film including a layer containing a polylactic acid polymer.

[0004]

Patent Document 1

Summary of the Invention

[0005] When the inventors of the present application examined a cover tape containing a biomass-derived resin, they found that simply replacing a petroleum-derived resin with a biomass-derived resin could not satisfy the mechanical properties required for the cover tape.

[0006] Therefore, an object of the present invention is to provide an environmentally considerate cover tape containing a certain amount of a biomass-derived resin, which can achieve mechanical properties equivalent to those of a conventional cover tape, and an electronic component package containing the same.

[0007] In response to the above problems, as a result of intensive studies by the inventors of the present application, a cover tape in which a base material layer, a support layer, and a heat seal layer are laminated in this order, wherein the support layer contains a linear low-density polyolefin resin (A) and a polyolefin resin (B) other than the resin (A), and the ratio of the biomass-derived linear low-density polyolefin resin (a1) to the total mass of the resin (A) is 0 to 50% by mass, and the ratio of the biomass-derived polyolefin resin (b1) to the total mass of the resin (B) is 50 to 100% by mass. Surprisingly, it has been found that a cover tape can achieve mechanical properties equivalent to those of a conventional cover tape while containing a certain amount of a biomass-derived resin.

[0008] According to the present invention, it is possible to provide an environmentally considerate cover tape containing a certain amount of a biomass-derived resin, which can achieve mechanical properties equivalent to those of a conventional cover tape, and an electronic component package containing the same.

Brief Description of the Drawings

[0009]

Figure 1

Figure 2

Mode for Carrying Out the Invention

[0010] Hereinafter, an embodiment of the present disclosure will be described in detail. However, the scope of the present disclosure is not limited to the embodiment described here, and various modifications can be made without departing from the spirit of the present disclosure. Each aspect disclosed in this specification can be combined with any other feature disclosed in this specification. Also, when a plurality of upper limit values and lower limit values are described for a specific parameter, any upper limit value and lower limit value among these can be combined to form a suitable numerical range. Further, the lower limit value and / or upper limit value of the numerical range described in the present disclosure may be a numerical value within that numerical range and may be replaced with the numerical values shown in the examples. The expression "X to Y" indicating a numerical range means "X or more and Y or less". When a specific description given for one embodiment also applies to other embodiments, the description may be omitted in other embodiments.

[0011] Each configuration and their combinations in each embodiment are examples, and within the scope not departing from the gist of the present disclosure, addition, omission, substitution, and other changes of the configuration can be made as appropriate. The present disclosure is not limited by the embodiments. Each aspect disclosed in this specification can be combined with any other feature disclosed in this specification.

[0012] [Cover Tape] The first embodiment in the present disclosure relates to a cover tape. The first embodiment relates to a cover tape, in which the cover tape has a base material layer, a support layer, and a heat-sealing layer laminated in this order, the support layer contains linear low-density polyolefin resin (A) and polyolefin resin (B) other than the resin (A), the ratio of biomass-derived linear low-density polyolefin resin (a1) to the total mass of the resin (A) is 0 to 50% by mass, and the ratio of biomass-derived polyolefin resin (b1) to the total mass of the resin (B) is 50 to 100% by mass. According to the cover tape according to the first embodiment, it is an environmentally considerate cover tape containing a certain amount of biomass-derived resin, and can achieve mechanical properties equivalent to those of conventional cover tapes. In the cover tape according to the first embodiment, "being able to achieve mechanical properties equivalent to those of conventional cover tapes" includes being able to achieve laminate strength and tape break strength comparable to those of conventional cover tapes that do not contain biomass-derived components.

[0013] The cover tape according to the first embodiment has a structure in which, for example, as shown in FIG. 1, a base material layer 1, a support layer 2, and a heat-sealing layer 3 are laminated in this order. Among these, by blending biomass-derived resin (a1) and / or resin (b1) in the support layer 2, the above-mentioned problems can be solved.

[0014] <Base material layer> The cover tape according to the first embodiment includes a base material layer. The base material layer preferably has mechanical strength and heat resistance that can withstand stress and heat history applied from the outside during the manufacture of the cover tape or the manufacture of an electronic component package. Further, from the viewpoint of easy processing, the material constituting the base material layer is preferably in a form processed into a film shape.

[0015] The above characteristics of the base material layer can be adjusted by appropriately selecting the materials constituting the same. Specific examples of the materials constituting the base material layer include, for example, polyester resins, polyamide resins, polyolefin resins, polyacrylate resins, polymethacrylate resins, polyimide resins, polycarbonate resins, acrylonitrile-butadiene-styrene (ABS) resins, and the like. Among them, from the viewpoint that the mechanical properties and flexibility of the cover tape according to the first embodiment are likely to be improved, it is preferable to use polyester resins and polyamide resins. The base material layer may further contain additives such as lubricants.

[0016] The base material layer may be a single-layer film containing the above-described materials, or may be a multilayer film containing the above-described materials in each layer. Further, the film used to form the base material layer may be an unstretched film, or may be a film stretched in a uniaxial direction or a biaxial direction. In one embodiment, from the viewpoint that the mechanical strength of the cover tape is likely to be improved, a film stretched in a uniaxial direction or a biaxial direction is preferable, and a film stretched in a biaxial direction (biaxially stretched film) is more preferable. In a particularly preferred embodiment, the base material layer is a biaxially stretched polyethylene terephthalate film. In one embodiment, from the viewpoint of obtaining a cover tape with a high biomass content, the base material layer may contain polyethylene terephthalate derived from biomass.

[0017] From the viewpoint that the laminating strength of the cover tape and the heat sealability with the carrier tape are likely to be good, the thickness of the base material layer is preferably 12 to 25 μm. The thickness of the base material layer can be appropriately adjusted within the above range.

[0018] In one embodiment, as the base material layer, one coated or kneaded with an antistatic agent for antistatic treatment, or one subjected to corona treatment, easy adhesion treatment, or the like can be used. In a preferred embodiment, an antistatic layer can be provided on the surface of the base material layer on the side where the support layer is not laminated. Hereinafter, the antistatic layer provided on the surface of the base material layer on the side where the support layer is not laminated will be described as the "antistatic layer I".

[0019] (Antistatic layer (I)) The antistatic layer (I) can contain a binder resin and an antistatic agent (hereinafter, the binder resin and the antistatic agent contained in the antistatic layer (I) will be referred to as "binder resin (I)" and "antistatic agent (I)"). As the antistatic agent (I), an inorganic antistatic agent; conductive fine particles such as barium sulfate, tin oxide, zinc oxide, indium oxide, titanium oxide, aluminum oxide, antimony-doped tin oxide (ATO); an ionic liquid containing a cyclic quaternary nitrogen-containing cation; a cationic surfactant such as a quaternary ammonium salt; a polyalkylene oxide (for example, polyethylene glycol, polypropylene glycol, polybutylene glycol, ethylene oxide-propylene oxide copolymer, etc.), a polyalkylene glycol such as a polyether ester having a polyoxyalkylene structure and an ester bond, etc. can be selected. Among these, from the viewpoint of easily controlling the surface resistivity on the base material layer side within a suitable range and easily obtaining a cover tape with few petroleum-derived components, the antistatic agent (I) preferably contains an inorganic antistatic agent. Examples of the inorganic antistatic agent include any one of magnesium silicate, smectite, montmorillonite, beidellite, nontronite, hectorite, saponite, or a combination thereof. Among these, it is preferable to contain magnesium silicate. The inorganic antistatic agent is preferably contained in the range of 40 to 80% by mass based on the total (100% by mass) of all components constituting the antistatic layer (I).

[0020] Examples of the binder resin (I) include thermoplastic resins selected from the group consisting of polyurethane resins, acrylic resins, polyvinyl chloride resins, ethylene-vinyl acetate resins, polyester resins, butadiene resins, styrene resins, acrylic-modified polyester resins, polyolefin resins, and combinations thereof. Among these, polyester resins or polyolefin resins are preferred, and it is preferred to include polyethylene resins. When a polyethylene resin is employed as the binder resin (I), a polyethylene resin derived from biomass (for example, a low-density polyethylene resin derived from biomass described later, etc.) may be used as the polyethylene resin.

[0021] From the viewpoint of easily achieving a desired surface resistivity, the thickness of the antistatic layer I is preferably 0.1 to 1.0 μm.

[0022] <Support layer> The cover tape according to the first embodiment includes a support layer provided on the base material layer. The support layer includes a linear low-density polyolefin resin (A) and a polyolefin resin (B) other than the resin (A), and the ratio of the linear low-density polyolefin resin (a1) derived from biomass to the total mass of the resin (A) is 0 to 50% by mass, and the ratio of the polyolefin resin (b1) derived from biomass to the total mass of the resin (B) is 50 to 100% by mass. In the cover tape according to the first embodiment, in this way, by using the resin derived from biomass blended in the support layer as the resin (a1) and / or the resin (b1) derived from biomass and controlling the ratio thereof, the biomass degree of the cover tape can be made not less than a certain value while achieving mechanical properties equivalent to those of conventional cover tapes.

[0023] (Linear low-density polyolefin resin (A)) The support layer contains a linear low-density polyolefin resin (A). Further, the resin (A) contains 0 to 50% by mass of a biomass-derived linear low-density polyolefin resin (a1) based on the total mass of the resin (A). That is, the resin (A) consists only of a petroleum-derived linear low-density polyolefin resin or is a resin in which a part thereof is replaced with a biomass-derived linear low-density polyolefin resin (a1).

[0024] As the petroleum-derived linear low-density polyolefin resin contained in the resin (A), from the viewpoint of having flexibility and appropriate rigidity and being likely to have good tear strength at room temperature (for example, tape break strength described later), a linear low-density polyethylene resin or a linear low-density polypropylene resin is preferable, and it is more preferable to contain a linear low-density polyethylene resin (LLDPE). As the petroleum-derived LLDPE, it is preferable to use a resin having a density in the range of 0.880 to 0.925 g / cm 3 of the range.

[0025] The petroleum-derived LLDPE includes those polymerized with a Ziegler catalyst and those polymerized with a metallocene catalyst (m-LLDPE). Among these, m-LLDPE has a narrow molecular weight distribution and is thus likely to obtain higher tear strength.

[0026] Petroleum-derived m-LLDPE is a copolymer of ethylene and an olefin having 3 or more carbon atoms as a comonomer, preferably an α-olefin having a linear, branched, or aromatic group with 3 to 18 carbon atoms. Examples of linear monoolefins include propylene, 1-butene, 1-pentene, 1-hexene, 1-octene, 1-nonene, 1-decene, 1-dodecene, 1-tetradecene, 1-hexadecene, 1-octadecene, etc. Examples of branched monoolefins include 3-methyl-1-butene, 3-methyl-1-pentene, 4-methyl-1-pentene, 2-ethyl-1-hexene, etc. Examples of monoolefins having an aromatic group include styrene, etc. These comonomers can be copolymerized with ethylene alone or in combination of two or more. In this copolymerization, polyenes such as butadiene, isoprene, 1,3-hexadiene, dicyclopentadiene, 5-ethylidene-2-norbornene, etc. may be copolymerized.

[0027] · Biomass-derived linear low-density polyolefin resin (a1) As the resin (a1) contained in the resin (A), it is a linear low-density polyolefin resin obtained by polymerizing a monomer containing an olefin monomer such as an ethylene monomer or a propylene monomer, which is chemically reaction-purified using plant-derived ethanol or propanol as a raw material and produced from renewable natural raw materials (e.g., corn, sugarcane, beet, manioc, etc.). The natural raw material of the resin (a1) is not particularly limited, but it preferably contains a resin derived from sugarcane. Since the resin derived from sugarcane is obtained by utilizing by-products generated in the sugar production process, it is more likely to be a cover tape with less environmental impact, and furthermore, the mechanical properties of the cover tape are likely to be improved. It is preferable to select the same resin as the petroleum-derived linear low-density polyolefin resin that constitutes the resin (A) for the resin (a1). In a preferred embodiment, when the resin (A) contains a linear low-density polyethylene resin (LLDPE), it is preferable that the resin (a1) also contains a biomass-derived linear low-density polyethylene resin (biomass-derived LLDPE). In one embodiment, the biomass-derived LLDPE is preferably a plant-derived LLDPE obtained by copolymerizing a plant-derived ethylene monomer and an α-olefin having 4 to 6 carbon atoms. Note that the resin (a1) may contain two or more biomass-derived linear low-density polyolefin resins.

[0028] From the viewpoint that the biomass-derived LLDPE is likely to exhibit physical properties equivalent to those of the petroleum-derived LLDPE, a copolymer of an olefin having 3 or more carbon atoms, preferably a linear, branched, or aromatic group-containing α-olefin having 3 to 18 carbon atoms and an ethylene monomer is preferred as the comonomer, similar to the petroleum-derived LLDPE. More preferably, the comonomer is butene-1 (C4).

[0029] In one embodiment, the density of the biomass-derived LLDPE is preferably 0.910 to 0.925 g / cm 3 more preferably 0.910 to 0.920 g / cm 3 even more preferably 0.913 to 0.918 g / cm 3 Here, the density of the biomass-derived LLDPE can be measured in accordance with JIS K 7112.

[0030] In one embodiment, the MFR (190 °C, load 2.16 N) of the biomass-derived LLDPE is preferably 0.5 to 4.0 g / 10 min, more preferably 1.5 to 3.0 g / 10 min, and even more preferably 2.0 to 2.5 g / 10 min.

[0031] In one embodiment, as the resin (a1), it is preferable to use a resin having a biomass degree of 80 to 100% as measured by radiocarbon dating 14C. A particularly preferred embodiment of the resin (a1) is biomass-derived LLDPE having a biomass degree of 80 to 100%.

[0032] Here, the "biomass degree by radiocarbon dating 14C" (biomass degree in the present disclosure) is the ratio of the biomass-derived component in the resin, obtained by measuring the concentration of 14C (radioactive carbon 14, half-life 5730 years) by accelerator mass spectrometry (AMS method). Since the carbon of petroleum-derived resins does not contain 14C, the ratio of the biomass-derived component in the resin can be determined by measuring the concentration of this 14C. The biomass degree can be measured by the following method. (Measurement method of biomass degree (AMS method)) The sample to be measured is burned to generate carbon dioxide. After purifying the generated carbon dioxide in a vacuum line, it is reduced with hydrogen using iron as a catalyst to generate graphite. The generated graphite is mounted on a dedicated 14C-AMS device based on a tandem accelerator (for example, manufactured by NEC Corporation) to measure the count of 14C, the concentration of 13C (13C / 12C), and the concentration of 14C (14C / 12C). The ratio of the 14C concentration of the sample carbon to the standard modern carbon is calculated from the obtained measurement values. In this measurement, oxalic acid (HO x II) provided by the National Institute of Standards and Technology (NIST) of the United States is used as the standard sample.

[0033] The proportion of the resin (a1) contained in the resin (A) is 0 to 50% by mass. The inventors of the present application have found that by blending the linear low-density polyolefin resin (A) and the polyolefin resin (B) other than the resin (A) in the support layer of the cover tape, and further controlling the proportion of the biomass-derived resin (a1) in the resin (A) to be low, it is possible to achieve mechanical properties equivalent to those of conventional cover tapes while being an environmentally considerate cover tape. From the perspective of easily maintaining the mechanical properties of the cover tape, the proportion of the resin (a1) in the resin (A) is preferably lower. In one embodiment, the proportion of the resin (a1) in the resin (A) is preferably 0 to 40% by mass, more preferably 0 to 30% by mass, and even more preferably 0 to 25% by mass. Further, it is particularly preferred that the resin (A) does not contain the resin (a1) (that is, the resin (A) contains only a linear low-density polyolefin resin derived from petroleum).

[0034] In a preferred embodiment, the resin (A) may be a resin containing only petroleum-derived LLDPE or a resin in which a part (50% by mass or less) of the petroleum-derived LLDPE is replaced by biomass-derived LLDPE.

[0035] (Polyolefin resin (B) other than resin (A)) The support layer contains the aforementioned resin (A) and a polyolefin resin (B) other than the resin (A). Further, the resin (B) contains 50 to 100% by mass of a biomass-derived polyolefin resin (b1) with respect to the total mass of the resin (B). That is, the resin (B) is a resin in which a part or all of the petroleum-derived polyolefin resin other than the resin (A) is replaced by a biomass-derived polyolefin resin (excluding the resin (a1)).

[0036] Examples of the petroleum-derived polyolefin resin contained in the resin (B) include polyethylene resins such as low-density polyethylene resin and ultra-low density polyethylene resin; copolymers of ethylene and α-olefin such as ethylene-propylene copolymer, ethylene-1-butene copolymer, ethylene-1-pentene copolymer, ethylene-1-hexene copolymer, ethylene-1-octene copolymer, and ethylene-vinyl acetate copolymer; copolymers of ethylene and other monomers such as ethylene-acrylic ester copolymer, ethylene-maleic acid copolymer, styrene-ethylene graft copolymer, styrene-propylene graft copolymer, and styrene-ethylene-butadiene block copolymer; and polypropylene resins such as homopolypropylene resin and random polypropylene resin. Among these, from the viewpoint of easier improvement in processability, it is preferable to contain a polyethylene resin or a polypropylene resin, and low-density polyethylene resin (LDPE) is more preferable.

[0037] · Biomass-derived polyolefin resin (b1) The resin (b1) contained in the resin (B) is a polyolefin resin obtained by polymerizing olefin monomers such as ethylene monomer and propylene monomer, which are chemically reacted and purified using plant-derived ethanol and propanol produced from renewable natural raw materials (e.g., corn, sugarcane, beet, manioc, etc.), similar to the resin (a1). The natural raw material of the resin (b1) is not particularly limited, but a plant-derived resin is preferable, and it is preferable to contain a resin derived from sugarcane. If it is a resin derived from sugarcane, it is more likely to be a cover tape with less environmental impact, and furthermore, the mechanical properties of the cover tape are also likely to be improved.

[0038] It is preferable to select the resin (b1) as the same resin as the petroleum-derived polyolefin resin constituting the resin (B). In a preferred embodiment, when the resin (B) contains a low-density polyethylene resin (LDPE), it is preferable that the resin (b1) also contains a biomass-derived low-density polyethylene resin (biomass-derived LDPE). In one embodiment, the biomass-derived LDPE may be a plant-derived LDPE. Note that the resin (b1) may contain two or more biomass-derived low-density polyolefin resins.

[0039] In one embodiment, the density of the biomass-derived LDPE is preferably 0.910 to 0.930 g / cm 3 and more preferably 0.915 to 0.925 g / cm 3 and even more preferably 0.918 to 0.925 g / cm 3 The density of the biomass-derived LDPE can be measured in the same manner as the density of the aforementioned biomass-derived LLDPE.

[0040] In one embodiment, the MFR (190 °C, load 2.16 N) of the biomass-derived LDPE is preferably 0.1 to 2.0 g / 10 min, more preferably 0.1 to 1.0 g / 10 min, and even more preferably 0.1 to 0.5 g / 10 min.

[0041] In one embodiment, as the resin (b1), it is preferable to use a resin having a biomass degree of 80 to 100% as measured by the aforementioned radiocarbon dating 14C, and more preferably 90 to 100%. A particularly preferred embodiment of the resin (b1) is the biomass-derived LDPE having a biomass degree of 80 to 100%.

[0042] From the viewpoint of maintaining a high biomass content in the cover tape while making it easier for the mechanical properties of the cover tape to be good, it is preferable that the proportion of resin (b1) in resin (B) is higher. In one embodiment, the proportion of resin (b1) in resin (B) is preferably 60 to 100% by mass, more preferably 70 to 100% by mass, and even more preferably 80 to 100% by mass. Further, from the viewpoint of maintaining a high biomass content while improving the mechanical properties of the cover tape, it is particularly preferable that resin (B) contains only resin (b1) (that is, resin (B) does not contain a polyolefin resin derived from petroleum).

[0043] In a preferred embodiment, resin (B) may be a resin containing only LDPE derived from biomass, or a resin in which a part (50% by mass or less) of the LDPE derived from biomass is replaced by LDPE derived from petroleum.

[0044] In one embodiment, the proportion of resin (A) with respect to the total (100% by mass) of resin (A) and resin (B) in the support layer is preferably 50 to 70% by mass, and more preferably 55 to 70% by mass. If the proportion of resin (A) is within the above range, it is easy to achieve a mechanical strength comparable to that of a conventional cover tape while maintaining a high biomass content in the cover tape.

[0045] In one embodiment, the total amount of the biomass-derived resin containing resin (b1) in the support layer is preferably 30% by mass or more with respect to the total mass of the resin components constituting the support layer. If the proportion of the biomass-derived resin is 30% by mass or more, the biomass content of the cover tape is likely to be high, and the cover tape is likely to be environmentally friendly. On the other hand, if the proportion of the biomass-derived resin becomes too high, the mechanical strength of the cover tape is likely to decrease. Therefore, from the viewpoint of easily maintaining a high mechanical strength of the cover tape, the total amount of the biomass-derived resin containing resin (b1) in the support layer is preferably 30% by mass or more and less than 70% by mass, more preferably 30 to 60% by mass, and even more preferably 30 to 50% by mass.

[0046] In a preferred embodiment, the support layer contains only a mixture of resin (A) and resin (B) as the resin component. When the support layer contains only the mixture as the resin component, the total amount of resin (a1) and resin (b1) in the mixture (i.e., the total amount of biomass-derived components) is preferably 30% by mass or more based on the total mass of the mixture. From the viewpoint of the mechanical strength of the cover tape, the total amount of resin (a1) and resin (b1) is preferably 30% by mass or more and less than 70% by mass, more preferably 30 to 60% by mass, and even more preferably 30 to 50% by mass.

[0047] In one embodiment, when the support layer contains only the mixture as the resin component, the ratio of resin (b1) to the total mass of the mixture is preferably 30 to 50% by mass, more preferably 35 to 50% by mass, and even more preferably 35 to 45% by mass.

[0048] In one embodiment, the thickness of the support layer is preferably 5 to 50 μm, more preferably 10 to 40 μm. If the thickness of the support layer is within the above range, it is easy to alleviate the heat seal marks on the cover film when heat-sealing the cover film to the carrier tape, and the peel strength during heat-sealing is likely to be good.

[0049] <Heat-sealing layer> The cover tape according to the first embodiment has a base material layer, a support layer, and a heat-sealing layer laminated in this order. The heat-sealing layer is made of a thermoplastic resin that has heat-sealing properties with respect to the carrier tape and exhibits easy peelability that can be easily peeled from the carrier tape as needed. For example, a molten mixture of the following resin (C) and resin (D) can be used. (Resin (C)) At least one resin selected from polyethylene resins (for example, various polyethylene resins such as low-density polyethylene and linear low-density polyethylene) and ethylene copolymers (for example, ethylene-vinyl acetate copolymer, ethylene-ethyl acrylate copolymer, and ethylene-butene-1 copolymer). (Resin (D)) At least one resin selected from polystyrene and styrenic resins containing styrene as a copolymerization component (for example, styrene-butadiene copolymer, hydrogenated product of styrene-butadiene copolymer, styrene-isoprene copolymer, hydrogenated product of styrene-isoprene copolymer, styrene-butene-butadiene copolymer, copolymer of methacrylic acid and styrene, impact-resistant polystyrene, etc.). In addition, as the polyethylene resin in the resin (C), a biomass-derived resin such as the aforementioned resin (a1) or resin (b1) may be used. When the heat-sealing layer contains a biomass-derived resin, it is preferably 40% by mass or less based on the total mass of the resin composition constituting the heat-sealing layer.

[0050] Among the melt mixtures of the above resin (C) and resin (D), from the viewpoint of the peel strength being continuously and easily stabilized when heat-sealed to the carrier tape and then peeled from the carrier tape, a melt mixture of an ethylene copolymer and at least one resin selected from the group consisting of a styrene-butadiene copolymer and an impact-resistant polystyrene resin is preferred. Furthermore, as the ethylene copolymer in the above mixture, an ethylene-butene-1 copolymer is particularly preferred.

[0051] In a preferred embodiment, when the heat-sealing layer is composed of a mixture of resin (C) and resin (D), when the mixture is 100% by mass, a mixture containing 15 to 60% by mass of an ethylene copolymer and 40 to 85% by mass of a styrene-butadiene copolymer is more preferred in terms of the stability of the peel strength.

[0052] In one embodiment, the thickness of the heat-sealing layer is preferably 3 to 25 μm, more preferably 5 to 20 μm. If the thickness of the heat-sealing layer is within the above range, good peel strength is easily obtained and the variation in peel strength is less likely to occur.

[0053] In one embodiment, the heat-sealing layer can be one to which an antistatic agent for antistatic treatment is applied or kneaded, or one that has been subjected to corona treatment, easy adhesion treatment, or the like. In a preferred embodiment, an antistatic layer can be provided on the surface of the heat-sealing layer on the side where the support layer is not laminated. Hereinafter, the antistatic layer provided on the surface of the heat-sealing layer on the side where the support layer is not laminated will be described as the "antistatic layer (II)".

[0054] (Antistatic layer (II)) Similar to the antistatic layer (I), the antistatic layer (II) can also contain a binder resin and an antistatic agent (hereinafter, the binder resin and the antistatic agent contained in the antistatic layer (II) will be referred to as "binder resin (II)" and "antistatic agent (II)"). As the antistatic agent (II), similar to the antistatic agent (I), it can be selected from inorganic antistatic agents; conductive fine particles such as barium sulfate, tin oxide, zinc oxide, indium oxide, titanium oxide, aluminum oxide, antimony-doped tin oxide (ATO); ionic liquids containing cyclic quaternary nitrogen-containing cations; cationic surfactants such as quaternary ammonium salts; polyalkylene oxides (for example, polyethylene glycol, polypropylene glycol, polybutylene glycol, ethylene oxide-propylene oxide copolymer, etc.), polyalkylene glycols such as polyether esters having a polyoxyalkylene structure and an ester bond. Since the antistatic layer (II) is provided on the surface in contact with the contents such as electronic components when used as an electronic component package, it is preferably a layer with a lower surface resistivity. For example, the surface resistivity of the surface of the antistatic layer (II) is preferably 10 12 Ω or less. From the viewpoints of the aforementioned surface resistivity, heat-sealability with the carrier tape, and easy reduction of the proportion of petroleum-derived components in the cover tape, conductive fine particles are preferred as the antistatic agent (II), and it is more preferred to contain aluminum oxide. The proportion of the antistatic agent (II) is preferably 100 to 1000 parts by mass, and more preferably 100 to 700 parts by mass, based on 100 parts by mass of the binder resin (II) described later.

[0055] As the binder resin (II), a (meth)acrylic resin is preferred from the viewpoint that the releasability from the carrier tape, particularly the high-speed releasability, is likely to be good. The (meth)acrylic resin is not particularly limited. For example, acrylic esters such as methyl acrylate, ethyl acrylate, propyl acrylate, and butyl acrylate, and methacrylic esters such as methyl methacrylate, ethyl methacrylate, propyl methacrylate, butyl methacrylate, and cyclohexyl methacrylate, and resins containing 50% by mass or more of at least one or more (meth)acrylic residues can be mentioned. These may be used alone or in combination of two or more.

[0056] From the viewpoints of antistatic properties and peel strength, the thickness of the antistatic layer (II) is preferably 0.1 to 2.0 μm, more preferably 0.15 to 1.0 μm.

[0057] (Laminated layer) In one embodiment, a laminated layer may be provided between the support layer and the base material layer. By providing the laminated layer, the lamination strength of the cover tape is likely to be improved. The laminated layer may be provided directly on one side of the base material layer, for example, or may be provided via an anchor coat layer. That is, when providing the laminated layer, it may be provided in the order of "base material layer / laminated layer / support layer / heat seal layer", or may be provided in the order of "base material layer / anchor coat layer / laminated layer / support layer / heat seal layer". As the resin constituting the laminated layer, LLDPE having particularly flexibility, moderate rigidity, and excellent tear strength at normal temperature can be preferably used, and petroleum-derived LLDPE is more preferable. Among these, in particular, by using LLDPE in the range of a density of 0.880 to 0.925 g / cm 3 When LLDPE is used in this range, the laminated layer is less likely to protrude from the end of the cover film due to heat and pressure during heat sealing. In addition, since the heat seal coat unevenness due to the softening of the laminated layer during heat sealing of the cover film is easily alleviated, a stable peel strength is easily obtained when peeling the cover film.

[0058] As described above, LLDPE includes LLDPE polymerized with Ziegler catalysts and m-LLDPE. Among these, from the viewpoint of easily exhibiting high tear strength, it is preferable to use m-LLDPE (more preferably m-LLDPE derived from petroleum) for the laminate layer. Here, it is preferable to use LLDPEs with different densities for the laminate layer and the resin (A) in the support layer. In one embodiment, the laminate layer has a density of 0.910 g / cm 3 or more and 0.916 g / cm 3 less of m-LLDPE, and the resin (A) in the support layer preferably uses m-LLDPE of 0.916 g / cm 3 or more and 0.920 g / cm 3 or less.

[0059] In one embodiment, from the viewpoint of easily obtaining good laminate strength, the thickness of the laminate layer is preferably 10 to 20 μm.

[0060] For the cover tape according to the first embodiment, the biomass degree of the whole cover tape measured by the aforementioned AMS method is preferably 10% or more, and more preferably 12% or more. It is preferable to set the ratio of the biomass-derived resin in the support layer and other layers so that the biomass degree of the whole cover tape is 10% or more.

[0061] In one embodiment, the laminate strength of the cover tape measured by the method described later is preferably 6.5 N / 15 mm or more, and more preferably 7.0 N / 15 mm or more. The laminate strength of a conventional cover tape that does not contain a biomass-derived resin is, for example, about 7.0 N / 15 mm as shown in Reference Example 1. The cover tape according to the first embodiment can achieve a laminate strength comparable to that of a conventional cover tape while containing a biomass-derived resin. In addition, the cover tape is also required not to break when peeled off at a high speed of 100 m / min or more. The tape break during high-speed peeling can be evaluated, for example, by the tape break strength measured by the method described below. In a conventional cover tape with excellent high-speed peelability, the tape break strength at a high-speed needle is about 1.2 N. The cover tape according to the first embodiment can achieve a tape break strength comparable to that of the conventional cover tape. That is, in one embodiment, the tape break strength of the cover tape measured by the method described below may be 1.2 N or more, or may be 1.3 N or more.

[0062] [Manufacturing method of cover tape] The manufacturing method of the cover tape according to the first embodiment is not particularly limited, and a general method can be adopted. For example, the heat-sealing layer is previously formed into a film by a method such as the T-die casting method or the inflation method. Further, an anchor coating agent (anchor coating layer) such as polyurethane, polyester, polyolefin, or polyethyleneimine is applied to the surface of the base material layer (preferably, a biaxially stretched polyester film), and a resin composition (including resin (A) and resin (B). Preferably, a mixture of LLDPE and LDPE) constituting the support layer is extruded from a T-die between the coated surface of the anchor coating agent and the film of the heat-sealing layer, so that a three-layer cover tape in which the base material layer, the support layer, and the heat-sealing layer are laminated in this order can be obtained.

[0063] In one embodiment, when obtaining a cover tape in which a base material layer, a laminate layer, a support layer, and a heat seal layer are laminated in this order, the resin composition constituting the support layer and the resin composition constituting the heat seal layer are extruded from separate single-screw extruders and laminated with a multi-manifold die to create a two-layer film composed of the support layer and the heat seal layer. Further, the aforementioned anchor coating agent (anchor coating layer) is applied to the surface of the base material layer, and a resin composition (preferably, m-LLDPE) constituting the laminate layer is extruded from a T-die between the coated surface of the anchor coating agent and the two-layer film, whereby a four-layer cover tape composed of the base material layer, the laminate layer, the support layer, and the heat seal layer can be obtained.

[0064] In addition to the above steps, if necessary, antistatic layers (I) and (II) can be provided on the surface of the base material layer of the cover film and / or on the surface of the heat seal layer. The antistatic layers (I) and (II) can be provided by coating a resin composition constituting the antistatic layer (I) or (II) on a predetermined surface of each layer using a roll coater, a lip coater, a spray, etc. using a gravure roll. Also, before performing the antistatic treatment, the surface of the base material layer or the heat seal layer may be subjected to corona discharge treatment or ozone treatment.

[0065] [Use] The cover tape according to the first embodiment can be used as a cover tape for an electronic component package.

[0066] [Electronic Component Package] The second embodiment is an electronic component package including the cover tape according to the first embodiment. The electronic component package according to the second embodiment is obtained, for example, by storing electronic components or the like in a depression for storing electronic components such as those on a carrier tape, and then using the cover tape according to the first embodiment as a lid material, continuously heat-sealing both longitudinal edges of the cover tape using a heat-seal coat or the like for packaging, and winding it around a reel. The electronic components or the like packaged in this form are stored and transported. The package according to this embodiment can be used for storing and transporting various electronic components such as connectors, ICs, diodes, transistors, capacitors, resistors, and LEDs.

[0067] The electronic component package is intermittently peeled off the cover tape while being transported using holes called sprocket holes for transporting the carrier tape provided at the longitudinal edges of the carrier tape, and the electronic components are taken out while confirming the presence, orientation, and position of the electronic components or the like by a component mounting device, and mounted on a substrate.

[0068] The carrier tape included in the electronic component package according to the second embodiment is a strip-shaped material having a width of about 8 mm to 100 mm with a depression for storing electronic components. When heat-sealing with the cover tape according to the first embodiment as a lid material, the material constituting the carrier tape is not particularly limited, but a carrier tape containing a polystyrene-based resin, a polyester-based resin, or a polycarbonate-based resin can be preferably used. The carrier tape can be one imparted with conductivity by kneading carbon black or carbon nanotubes into the resin, one kneaded with a surfactant-type antistatic agent such as a cationic, anionic, or nonionic type or a persistent antistatic agent such as polyether ester amide, or one imparted with antistatic properties by applying a coating solution in which a surfactant-type antistatic agent or a conductive material such as polypyrrole or polythiophene is dispersed in an organic binder such as a (meth)acrylic resin on the surface.

Example

[0069] Hereinafter, the present invention will be described in detail with reference to examples, but the present invention is not limited by the following description.

[0070] [Examples 1 to 3, Comparative Examples 1 to 3, and Reference Example 1] After pre-blending the following resins (C) and (D), they were kneaded using a single-screw extruder to obtain a resin composition for a heat-sealing layer. The resin composition for the heat-sealing layer and the resin composition for the support layer described in Table 1 were each extruded from an individual single-screw extruder and laminated and extruded using a multi-manifold T-die to obtain a two-layer film with a heat-sealing layer and a support layer having thicknesses of 5 μm and 20 μm, respectively. Next, a two-component curable polyurethane-type anchor coating agent was applied to the base material layer (thickness 13 μm) using a roll coater, and a molten resin composition constituting a laminate layer was extruded between the coated surface and the surface of the support layer of the above two-layer film so that the thickness was 13 μm, and a laminated film was obtained by the extrusion lamination method. After corona-treating the surface of the base material layer and the surface of the heat-sealing layer of the above laminated film, a resin composition for an antistatic layer (I) and a resin composition for an antistatic layer (II) were applied using a gravure coater so that the thickness after drying was 0.4 μm each, and a cover tape having a layer structure of antistatic layer I / base material layer / (anchor coat layer) / laminate layer / support layer / heat-sealing layer / antistatic layer (II) as shown in FIG. 2 was obtained. In FIG. 2, the display of the anchor coat layer is omitted.

[0071] The materials used in each example are as follows. <Base material layer> ·PET: Biaxially stretched polyethylene terephthalate film, thickness 13 μm. <Laminate layer> ·m-LLDPE1: m-LLDPE derived from petroleum (density: 0.92 g / cm 3 ) <Support layer> (Resin (A)) ·m-LLDPE2: m-LLDPE derived from petroleum (density: 0.918 g / cm 3 ) (Resin (a1)) · Biomass-derived LLDPE: LLDPE derived from plants (copolymer of plant-derived ethylene and hexene), MFR: 2.3 g / 10 min, density: 0.916 g / cm 3 , biomass content: approximately 84%). (Resin (B)) · LDPE: LDPE derived from petroleum (density: 0.922 g / cm 3 ). (Resin (b1)) · Biomass-derived LDPE: LDPE derived from plants (MFR: 0.32 g / 10 min, density: 0.923 g / cm 3 , biomass content: approximately 95%). <Heat-sealing layer> · Resin (C): Ethylene-α-olefin copolymer (density: 0.885 g / cm 3 ) · Resin (D): Styrene-butadiene block copolymer (density: 1.03 g / cm 3 ) <Antistatic layer (I)> · Resin composition for antistatic layer (I): Resin composition containing binder resin (I) (polyolefin resin) and antistatic agent (I) (magnesium silicate). <Antistatic layer (II)> · Resin composition for antistatic layer (II): Resin composition containing binder resin (II) ((meth)acrylic resin) and antistatic agent (II) (alumina).

[0072] <Measurement of biomass content (AMS method) of cover tape> For the cover tapes obtained in each example, the biomass content was measured by the following method. The results are shown in Table 1. (Method for measuring biomass content (AMS method)) The sample to be measured was burned to generate carbon dioxide. After purifying the generated carbon dioxide with a vacuum line, it was reduced with hydrogen using iron as a catalyst to produce graphite. The produced graphite was mounted on a dedicated 14C-AMS device (manufactured by NEC Corporation) based on a tandem accelerator, and the counting of 14C, the concentration of 13C (13C / 12C), and the concentration of 14C (14C / 12C) were measured. From the obtained measurement values, the ratio of the 14C concentration of the sample carbon to the standard modern carbon was calculated. In this measurement, oxalic acid (HO x II) provided by the National Institute of Standards and Technology (NIST) of the United States was used as the standard sample.

[0073] <Mechanical Property Evaluation of Cover Tape> (Lamination Strength) For the cover tapes obtained in each example, the lamination strength was measured by the following method. The results are shown in Table 1. Five samples with a width of 15 mm × a length of 250 mm were cut out from the cover tape. A cut was made in the upper part of the sample in the width direction, and the cut part was dipped in an ethanol solvent and torn using fingertips or tweezers so that only the lamination layer would stretch. While holding the stretched lamination layer with tweezers or the like and stretching it, it was slowly peeled off from the base material layer. When the lamination layer and the base material layer were peeled off, a small amount of ethanol solvent was applied to the peeled part and peeled off more slowly to create a gripping part (about 3 cm) of the sample. At this time, if a white part appeared on the base material layer surface, the base material layer and the lamination layer were peeled off until the white part disappeared. Next, the gripping part was sandwiched between the tensile fixtures of a small desktop testing machine (manufactured by Shimadzu Corporation, product name "EZ-TEST"), and the base material layer and the other layers were peeled off. The peeling speed was 200 mm / min, the measurement length was 50 mm, and the sample width was 15 mm. The resistance was measured with a load cell attached to the tensile fixture, and the maximum strength during the measurement was determined as the lamination strength.

[0074] (Tape Tear Strength) For the cover tapes obtained in each example, the tape tear strength was measured by the following method. The results are shown in Table 1. First, the cover tape (width 21.5 mm) obtained in each example was heat-sealed onto a 24.0-mm-wide polystyrene carrier tape (manufactured by Denka Co., Ltd.) using a taping machine (manufactured by Bangard Systems Co., Ltd., product name "VS-120") under the following conditions to obtain an electronic component package. 〇Sealing head width 0.5 mm × 2, sealing head length 32 mm, sealing pressure 5.0 Kg, feed length 16 mm, sealing time 0.4 seconds × 2 times, sealing cot temperature from 150°C to 200°C at 5°C intervals. First, a sample (length 500 mm × width 24.0 mm) of the electronic component package with a sealing cot temperature of 200°C was attached to a vertical wall with double-sided adhesive tape. At this time, the sample was attached so that the carrier tape side was in contact with the wall. Next, a load (1 kg) was applied to the upper part of the cover tape, and the cover tape was rapidly peeled from the carrier tape at a peeling speed of up to 180 m / min. Next, the same rapid peeling test was also carried out on samples with a sealing cot temperature from 150°C to 195°C. For samples at each temperature, the rapid peeling test was carried out 3 times each, and the test was carried out until the number of samples with a cut in the cover tape was 0 to 1 piece. Then, for all the samples for which the evaluation was carried out, the peeling strength was measured under the following conditions. Among all the samples, the peeling strength of the sample with a cut was taken as the minimum peeling strength, and the peeling strength of the sample without a cut was taken as the maximum peeling strength, and the average value of the minimum peeling strength and the maximum peeling strength was taken as the cut strength of the tape. (Measurement of peeling strength) A sample (length 300 mm × width 24.0 mm) was peeled at a peeling angle of 170 - 180° and a peeling speed of 300 mm / min using a peeling strength tester (manufactured by Bangard Systems Co., Ltd., product name "VG-35") to measure the peeling strength.

[0075] [Table 1]

[0076] As shown in Table 1, the cover tapes of Examples 1 to 3 that satisfy the configuration of the first embodiment had a high biomass content of 13 to 14.5% and were environmentally considerate cover tapes. Furthermore, the cover tapes of Examples 1 to 3 had laminate strength and tape break strength comparable to those of the conventional cover tape shown in Reference Example 1. Surprisingly, both the laminate strength and the tape break strength were improved compared to the cover tape of Reference Example 1. On the other hand, in the cover tapes of Comparative Examples 1 to 3 that did not satisfy the configuration of the first embodiment, both the laminate strength and the tape break strength were significantly reduced. From the above results, it was confirmed that the cover tape according to the first embodiment is an environmentally considerate cover tape containing a certain amount of biomass-derived resin, and can achieve mechanical properties equivalent to those of conventional cover tapes.

[0077] A non-limiting list of exemplary embodiments of the present disclosure and combinations of exemplary embodiments is described below. [1] A cover tape, wherein the cover tape has a base material layer, a support layer, and a heat seal layer laminated in this order, the support layer contains a linear low-density polyolefin resin (A) and a polyolefin resin (B) other than the resin (A), the ratio of the biomass-derived linear low-density polyolefin resin (a1) to the total mass of the resin (A) is 0 to 50% by mass, and the ratio of the biomass-derived polyolefin resin (b1) to the total mass of the resin (B) is 50 to 100% by mass. [2] The cover tape according to [1], wherein the biomass content of the entire cover tape measured by the AMS method is 10% or more. [3] The cover tape according to [1] or [2], wherein the total amount of the biomass-derived resin containing the resin (b1) in the support layer is 30% by mass or more based on the total mass of the resin components constituting the support layer. [4] The cover tape according to any one of [1] to [3], wherein the ratio of the resin (A) to the total of the resin (A) and the resin (B) (100% by mass) in the support layer is 50 to 70% by mass. [5] The resin (B) contains a low-density polyethylene resin, The cover tape according to any one of [1] to [4], wherein the resin (b1) contains a biomass-derived low-density polyethylene resin. [6] The resin (A) contains a linear low-density polyethylene resin, The cover tape according to any one of [1] to [5], wherein the resin (a1) contains a biomass-derived linear low-density polyethylene resin. [7] The support layer is composed of a mixture of the resin (A) and the resin (B), The cover tape according to any one of [1] to [6], wherein the total amount of the resin (a1) and the resin (b1) is 30% by mass or more based on the total mass of the mixture. [8] The cover tape according to any one of [1] to [7], which is for an electronic component package. [9] An electronic component package including the cover tape according to any one of [1] to [8].

Industrial Applicability

[0078] The cover tape according to the first embodiment can achieve mechanical properties equivalent to those of a conventional cover tape while containing a certain amount of biomass-derived resin. Therefore, it has industrial applicability as a cover tape for an electronic component package that takes environmental considerations into account.

Explanation of Symbols

[0079] 1: Base material layer 2: Support layer 3: Heat seal layer 4: Laminate layer 5: Antistatic layer (I) 6: Antistatic layer (II) 10, 20: Cover tape

Claims

1. A cover tape comprising: The cover tape includes a base layer, a support layer, and a heat seal layer laminated in this order, The support layer contains a linear low-density polyolefin resin (A) and a polyolefin resin (B) other than the resin (A), The ratio of the biomass-derived linear low-density polyolefin resin (a1) to the total mass of the resin (A) is 0 to 50 mass%; The cover tape has a biomass-derived polyolefin resin (b1) content of 50 to 100% by mass relative to the total mass of the resin (B).

2. 2. The cover tape according to claim 1, wherein the biomass ratio of the entire cover tape measured by the AMS method is 10% or more.

3. The cover tape according to claim 1 or 2, wherein the total amount of biomass-derived resins including the resin (b1) in the support layer is 30 mass% or more relative to the total mass of the resin components constituting the support layer.

4. The cover tape according to claim 1 or 2, wherein in the support layer, the proportion of the resin (A) with respect to the total (100 mass%) of the resin (A) and the resin (B) is 50 to 70 mass%.

5. The resin (B) comprises a low-density polyethylene resin, The cover tape of claim 1 or 2, wherein the resin (b1) comprises a biomass-derived low-density polyethylene resin.

6. The resin (A) contains a linear low-density polyethylene resin, The cover tape of claim 1 or 2, wherein the resin (a1) comprises a biomass-derived linear low-density polyethylene resin.

7. The support layer is made of a mixture of the resin (A) and the resin (B), The cover tape according to claim 1 or 2, wherein a total amount of the resin (a1) and the resin (b1) is 30 mass% or more relative to a total mass of the mixture.

8. 3. The cover tape according to claim 1 or 2, which is for use in packaging for electronic components.

9. An electronic component package comprising the cover tape of claim 1 or 2.

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