JP2012006658A - Chip type electronic component packaging cover tape - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a chip type electronic component packaging cover tape in which static electricity generated upon friction or stripping of the cover tape is suppressed, reduction in tape strength caused by width-narrowing of the cover tape and deterioration in transparency of the cover tape stored under a high temperature are suppressed and the peeling-off strength is held within a proper range.SOLUTION: There is provided the chip type electronic component packaging cover tape which is thermally sealed to an embossed carrier tape having a housing pocket for chip type electronic component, and the chip type electronic component packaging cover tape has a multi-layer structure composed of an antistatic layer including an antistatic agent, a substrate of biaxially oriented plastic film, an interlayer made of polyethylene, an adhesive layer which adheres the substrate and the interlayer, and a sealing layer which is thermally sealed to the embossed carrier tape, wherein the sealing layer is formed by dispersing conductive fine powder of metal oxide into a resin mixture of a thermoplastic elastomer resin, a tackiness-imparting resin and an acrylic resin.

Description

  The present invention relates to a chip-type electronic component packaging cover tape that covers, with heat seal, an opening surface of a storage unit for storing an electronic component of an embossed carrier tape used in a package for storing and transporting chip-type electronic components and the like. About.

  Conventionally, a component mounting method using a chip-type electronic component wrapping cover tape (hereinafter referred to as a cover tape) has a storage unit for individually storing it according to the shape of a small electronic component such as a resistor, a capacitor, a diode, and an IC chip. (Hereinafter referred to as a storage pocket) a paperboard punched carrier tape that has been punched to form a cover tape for covering the opening surface of the storage pocket with a heat seal, and a small electronic component There are two general types of embossed carrier tape that is embossed to form storage pockets that can be individually stored according to shape, and a cover tape that covers the opening surface of the storage pocket is covered with a heat seal. It has been adopted. Small electronic components are stored in a storage pocket, covered with a cover tape, stored in a package wound in a reel shape, transported, and used in automatic assembly equipment that mounts electronic components on an electronic circuit board Yes.

  When the cover tape is peeled from the embossed carrier tape, the strength to peel the cover tape is called peel strength (hereinafter referred to as peel-off strength). The phenomenon of jumping trouble popping out from the head is occurring. In order to solve this problem, the conventional cover tape mainly uses a cohesive failure type cover tape that can easily control the peel-off strength within an appropriate range and can obtain a stable peel-off strength over time. Yes. For example, the adhesive layer of the chip-type electronic component packaging cover tape is electrostatically treated to suppress static electricity generated during contact between the electronic component and the cover tape or peeling of the cover tape. A chip-type electronic component packaging cover tape that is stable to changes and does not affect the sealing performance has been introduced (see, for example, Patent Document 1).

JP-A-5-32288

  However, conventional chip-type electronic component packaging cover tapes require smaller, lighter and thinner shapes for electronic devices. Improvements in surface mounting technology and lighter, thinner and smaller electronic components such as ICs, resistors, and capacitors Accordingly, the embossed carrier tape is also narrowed, and the corresponding cover tape is also narrowed to increase the tape breakage strength for preventing the tape breakage.

  In addition, the package of chip-type electronic components wound in a reel shape peels off the static electricity generated when the inner side of the cover tape and the electronic components come into contact with each other due to vibration generated when the package is conveyed, or the cover tape is peeled off. There is a problem that the electronic component is charged by the static electricity generated when it is applied, and sticks to the cover tape and jumps out.

  In addition, it is necessary to increase the transparency of the cover tape to facilitate component identification by optical equipment. However, when stored at high temperatures, the cohesive failure type cover tape is blocked by the winding core and the tape base material. There is a problem that the transparency of the cover tape is greatly reduced.

  Further, the cover tape stored at a high temperature has a problem that the cohesive force of the adhesive layer is lowered due to a change with time and it is difficult to keep the peel-off strength within an appropriate range.

  Further, the peel-off strength of the currently commercialized cover tape (sealant SL1-1) was about 0.40N, but it is desired to commercialize a cover tape with a peel-off strength increased to 0.60N. .

  The present invention has been made paying attention to the above points, and the structure of the cohesive failure type cover tape includes an antistatic layer containing an antistatic agent, a base layer of a transparent biaxially stretched plastic film, a base layer and Conductive fine powder was uniformly dispersed in an interlayer adhesive layer for improving the lamination strength of the intermediate layer, an intermediate layer improved in cushioning function and tear resistance against heat and pressure, and a thermoplastic resin having transparency. An object of the present invention is to provide a chip-type electronic component packaging cover tape having a five-layer structure composed of a sealing layer of a conductive thermal adhesive layer, which can be used for high-speed peeling at a peel rate of 3000 mm / min.

  In addition, by providing the sealing layer with a mixed resin of an acrylic-modified polyolefin resin, a tackifying resin, and a styrene-based thermoplastic elastomer resin, it is possible to provide a chip-type electronic component packaging cover tape that further increases the peel-off strength. Objective.

  In order to achieve the above-mentioned object, the present invention has the following configurations (1) to (8).

  (1) A chip-type electronic component packaging cover tape that is heat-sealed to an embossed carrier tape in which a storage pocket for storing a chip-type electronic component is formed, comprising an antistatic layer containing an antistatic agent, polyethylene terephthalate, and polypropylene A biaxially stretched plastic film substrate made of any one of nylon (registered trademark), an intermediate layer made of polyethylene, an adhesive layer for bonding the substrate and the intermediate layer, and heat applied to the embossed carrier tape. The seal layer is formed of a resin mixture of a thermoplastic elastomer resin, a tackifier resin, and an acrylic resin, and the resin mixture includes tin oxide, zinc oxide, and oxide. A chip characterized in that conductive fine powder of metal oxide made of any one of indium is dispersed. For packaging electronic components cover tape.

  (2) The resin mixture constituting the seal layer is a dispersion of 14 to 49% by weight of the thermoplastic elastomer resin, 1 to 35% by weight of the tackifier resin, and 1 to 35% by weight of the acrylic resin. The chip-type electronic component packaging cover tape according to (1), wherein the metal oxide is 30 to 55% by weight.

  (3) The thermoplastic elastomer resin is any one of a styrene butadiene resin, a styrene butadiene styrene block copolymer resin, a styrene ethylene butylene styrene block copolymer resin, or a mixture thereof (1) ) Or (2) The chip-type electronic component packaging cover tape.

(4) The chip-type electronic component according to any one of (1) to (3), wherein the intermediate layer has a density of 0.8 to 0.909 g / cm ³ of polyethylene. Cover tape for packaging.

  (5) A chip-type electronic component packaging cover tape that is heat-sealed to an embossed carrier tape in which a storage pocket for storing the chip-type electronic component is formed, and includes an antistatic layer containing an antistatic agent, polyethylene terephthalate, and polypropylene A biaxially stretched plastic film substrate made of any one of nylon (registered trademark), an intermediate layer made of polyethylene, an adhesive layer for bonding the substrate and the intermediate layer, and heat applied to the embossed carrier tape. The sealing layer is formed of a resin mixture of an acrylic-modified polyolefin resin, a tackifying resin, and a thermoplastic elastomer resin, and the resin mixture includes tin oxide and zinc oxide. Conductive fine powder of metal oxide consisting of any one of indium oxide is dispersed. Chip-type electronic component packaging cover tape, wherein.

  (6) The resin mixture constituting the sealing layer is 40 to 90% by weight of the acrylic-modified polyolefin resin, 1 to 30% by weight of the tackifying resin, and 1 to 30% by weight of the thermoplastic elastomer resin. The chip-type electronic component packaging cover tape according to (5) above, wherein

  (7) The chip type according to (5) or (6), wherein the acrylic-modified polyolefin resin has an acrylic resin component in a range of 20 to 80% by weight and a polyolefin resin component in a range of 20 to 80% by weight. Cover tape for packaging electronic parts.

  (8) The chip mold according to any one of (5) to (7), wherein the thermoplastic elastomer resin is made of a styrene thermoplastic elastomer resin containing 30 to 70% by weight of a styrene component. Cover tape for packaging electronic parts.

  According to the present invention, static electricity due to friction between the electronic component and the cover tape, or static electricity generated when the cover tape is peeled off, is suppressed, and the tape strength is not reduced due to the narrowing of the cover tape, and stored at a high temperature. Even in this case, it is possible to provide a chip-type electronic component packaging cover tape that can suppress a decrease in transparency of the cover tape and can maintain the peel-off strength within an appropriate range.

  Further, it is possible to provide a chip-type electronic component packaging cover tape that can be used for high-speed peeling at a peel rate of 3000 mm / min.

  In addition, by providing the sealing layer with a mixed resin of an acrylic-modified polyolefin resin, a tackifying resin, and a styrene-based thermoplastic elastomer resin, it is possible to provide a chip-type electronic component packaging cover tape that further increases the peel-off strength. Objective.

The block diagram of the package of the chip-type electronic component containing the cover tape which concerns on the present Example 1, (a) The external view of the package of the chip-type electronic component, (b) AA cross section of the cover tape which concerns on a present Example Figure The figure which shows the basic performance of the cover tape which concerns on this Example 1 Three-component system phase diagram of the sealing layer constituting the cover tape according to the first embodiment The figure which shows the performance of the peel-off intensity | strength with respect to the kind of embossed carrier tape of the cover tape which concerns on this Example 1. The figure which shows the performance of the peel-off intensity | strength with respect to the kind of embossed carrier tape of the cover tape which concerns on this Example 1, (a) The graph of peel-off intensity with respect to a heat seal temperature change, (b) The graph of peel-off intensity with respect to an environmental change Three-component phase diagram in which the sealing layer of the cover tape according to the second embodiment has a different mixed composition ratio (A) Basic performance table according to composition of seal layer sealant of cover tape according to Example 2, (b) Diagram showing mixing ratio according to composition of seal layer sealant (A) a graph showing the peel-off strength of low speed and high speed peeling by composition of the seal layer sealant of the cover tape according to Example 2, (b) a graph showing the surface resistance value by composition of the seal layer sealant, ( c) Graph showing haze value by composition of seal layer sealant The figure which shows the test result of the peeling strength according to the sealing agent composition of the sealing layer of the cover tape which concerns on this Example 2.

  Hereinafter, embodiments for carrying out the present invention will be described in detail with reference to the drawings.

  As for the structure of the chip-type electronic component package and the cohesive failure type cover tape shown in FIG. 1, FIG. 1 (a) is an external view of the chip-type electronic component package, and FIG. 1 (b) is the present embodiment. It is AA sectional drawing of the cover tape which concerns. In the figure, 1 is an antistatic layer, 2 is a base material layer, 3 is an interlayer adhesive layer, 4 is an intermediate layer, 5 is a conductive thermal adhesive layer (hereinafter referred to as a seal layer), and 10 or 20 is a chip-type electronic device. A component packaging cover tape (hereinafter referred to as a cover tape), 11 is an embossed carrier tape having a storage pocket 11a, and 12 is a package of chip-type electronic components.

  The package 12 for chip-type electronic components shown in FIG. 1 (a) has a storage pocket 11a for storing electronic components formed on one side of an embossed carrier tape 11 by embossing, and covers the opening of the storage pocket 11a. The tape 10 is covered with a heat seal. The embossed carrier tape 11 is made narrower as the electronic parts become lighter, thinner, and the embossed carrier tape 11 is made of polystyrene (PS), polycarbonate because of the need to increase the strength of the tape to prevent the tape from being cut. An embossed carrier tape 11 of (PC) or amorphous polyethylene terephthalate (APET) is selected according to the application, and an antistatic agent is applied to the surface subjected to corona treatment as a countermeasure against static electricity. Therefore, the cover tape 10 of the cohesive failure type is also required to have a material for the cover tape 10 corresponding to these embossed carrier tapes 11.

  The structure of the cover tape 10 will be described with reference to the AA sectional view of the cover tape 10 according to this embodiment shown in FIG.

  The antistatic layer 1 serving as the outer surface is a conductive layer subjected to an antistatic treatment containing an antistatic agent. When the packaging body 12 is stored and transported, there is a function of suppressing static electricity generated by friction between the packaging body 12 and the embossed carrier tape 11.

  The base material layer 2 is a transparent biaxially stretched plastic film (specified by ISO14782 / 1468), a biaxially stretched polyethylene terephthalate (PET) plastic film, a biaxially stretched polypropylene (PP) plastic film, a biaxially stretched nylon (registered trademark). ) Select one of the plastic films according to the application. As the cover tape 10 becomes narrower, the thickness of the base material layer 2 is formed in the range of 6 to 100 μm because of the need to increase the tape break strength for preventing the tape breakage, and if the thickness of the layer is less than 6 μm, it is rigid. When the thickness exceeds 100 μm, it becomes too hard and adhesion by heat sealing becomes unstable. The thickness of the preferable base material layer 2 is in the range of 9 to 25 μm.

  In addition, the surface in contact with an interlayer adhesive layer 3 to be described later can be subjected to surface treatment such as corona treatment, plasma treatment, or sand blast treatment to improve the adhesion.

  The interlayer adhesive layer 3 is for the purpose of improving the tape breakage strength by laminating the base material layer 2 and the intermediate layer 4, and is a lacquer type with a polyurethane adhesive made of an isocyanate compound and an imine dry solidifying curing agent. By bonding the base material layer 2 and the intermediate layer 4 of different materials through the interlayer adhesive layer 3, the tape breakage strength is increased. The film thickness of the interlayer adhesive layer 3 is formed in the range of 0.5 to 5 μm, preferably in the range of 1 to 3 μm.

  The intermediate layer 4 is made of a polyethylene (PE) film, a polypropylene (PP) film, an ethylene vinyl acetate (EVA) film, and an ethylene methyl acrylate (EMA) film for the purpose of improving a cushion function and tear resistance against heat and pressure. , And an ionomer film or a polyolefin film are selected depending on the application.

In particular, on the side in contact with the seal layer 5, the cushion function and tear resistance can be improved by forming it with a single-layer or multilayer ultra-low density PE film having a density of 0.8 to 0.909 g / cm ³ . It has been.

  The seal layer 5 is a layer that is directly bonded to the above-described embossed carrier tape 11 by heat sealing, and is a heat-bonding lacquer in which conductive fine powder is uniformly dispersed in a thermoplastic resin having transparency for the purpose of preventing charging. It is a sealing layer made of an adhesive layer of a mold. The surface that contacts and rubs the electronic component stored in the storage pocket 11a of the embossed carrier tape 11 needs to be subjected to an antistatic treatment for preventing the electronic component from adhering or being destroyed by static electricity.

FIG. 2 is a table showing the basic performance of the cover tape 10 according to the present embodiment. According to the performance table, the thickness of the cover tape 10 is 52 μm according to the measurement method defined by ISO 4591, and has the tensile properties (tensile breaking strength, tensile breaking strain, tensile elastic modulus) defined by ISO 527-3. JIS K 7128-3 The tear resistance specified in JISK6911 of the cover tape 10 is 180 N / mm ² , the haze value specified in ISO 14782/13468 showing transparency is 18%, and the total light transmittance is 87% of 80% or more. The specified surface resistance values are 2E12 (2 × 10 ¹² ) Ω / □ for the open surface and 4E8 (4 × 10 ⁸ ) Ω / □ for the heat seal surface. The surface resistivity of the seal layer 5 is preferably 1E9 (1 × 10 ⁹ ) Ω / □ or less.

  FIG. 3 is a three-component phase diagram of the resin component of the seal layer, and is a diagram showing a particularly important mixed composition of the thermal adhesive layer in the cover tape 10 according to this embodiment. The material of the sealing layer 5 is a material having the same peel strength without depending on the type of the embossed carrier tape 11 as the counterpart material of the heat seal, by a transparent heat-bonding lacquer type single body or a combination thereof. Is good. Preferably, it is a resin mixture of a combination of a thermoplastic elastomer resin, a tackifier resin, and an acrylic resin, and the mixed composition of the region shown in the center of the ternary phase diagram is good.

  From the ternary phase diagram, the particularly preferred mixing ratio of each resin is 14 to 49% by weight for the thermoplastic elastomer resin, 1 to 35% by weight for the tackifying resin, and 1 to 35% by weight for the acrylic resin. Is a preferred range. The mixing ratio of the metal oxide in the conductive fine powder added as an antistatic agent is preferably 30 to 55% by weight.

  Next, each resin and metal oxide constituting the seal layer 5 will be described. The thermoplastic elastomer resin is selected from one or a mixture of styrene-based styrene butadiene (SB) resin, styrene butadiene styrene block copolymer (SBS) resin, and styrene ethylene butylene styrene block copolymer (SEBS) resin. Preferably, hydrogenated SEBS resin is used. The styrene / ethylene / butylene ratio of the hydrogenated SEBS resin is preferably 20/80 to 40/60% by weight, and the MFR indicating the fluidity of the resin under the condition that the extrusion pressure is 200 ° C. and 5 kgf is 2 to 7 g / A range of 10 minutes is good.

  As the tackifying resin, a coumarone resin, a phenol terpene resin, a petroleum hydrocarbon resin, a rosin derivative resin, or the like is used, and a petroleum hydrocarbon resin having a number average molecular weight of 400 to 2000 is preferable.

  As the acrylic resin, a mixture or copolymer of ethyl methacrylate (EMA) resin, methyl methacrylate (MMA) resin, butyl methacrylate (BMA) resin, isobutyl methacrylate (IBMA) resin is used, and preferably has a molecular weight of 5000 to 20000. Some acrylic polymer is good.

  The surface resistance value of the seal layer 5 is in the range of 10E5 to 10E14Ω / □, and preferably in the range of 10E6 to 10E13Ω / □. As the metal oxide of the conductive fine powder mixed as an antistatic agent, one type selected from tin oxide, zinc oxide, indium oxide, carbon black, and organic conductive compound is uniformly dispersed. The method for forming the seal layer 5 may be either a melt film forming method or a solution film forming method, but a solution film forming method is preferable from the viewpoint of dispersibility of metal oxides. The thickness of the seal layer 5 to be formed is in the range of 0.5 to 5 μm, preferably in the range of 1 to 3 μm, and when it exceeds 3 μm, formation by the solution casting method becomes difficult.

  FIG. 4 is a performance table of peel-off strength with respect to the type of embossed carrier tape 11 (PS carrier tape and PC carrier tape) to which the cover tape 10 of this embodiment is heat-sealed. A performance table of peel-off strength of the cover tape 10 with respect to differences in sealing temperature, peeling speed, and storage temperature when heat-sealing to different types of embossed carrier tapes 11 shown in FIG. 4 will be described.

  When the peel-off strength shown in this performance table is less than 0.4 N, there is a risk that the cover tape 10 may be peeled off due to vibration during transportation and the electronic component may fall, and the standard deviation value (SD) is an average value / 10. In the case of exceeding, it indicates that the vibration at the time of peeling increases and there is a risk of causing a jumping trouble that the electronic component jumps out of the storage pocket 11a.

  From the peel-off strength performance table shown in FIG. 4, the temperatures at which the cover tape 10 is heat sealed to the adherent PS carrier tape and PC carrier tape are 160 ° C. and 180 ° C., and the peeling rates are 3000 mm / min and 300 mm / min. Elapsed time after heat sealing, immediately after heat sealing, after storage at room temperature for 24 hours, and after packaging at 55 ° C. for 24 hours, the average value and standard deviation value of each peel-off strength were measured using a peel device. Value. As a result, the cover tape 10 heat-sealed to each embossed carrier tape 11 does not have a peel-off strength of less than 0.4 N that is peeled off due to vibration during transportation, etc. The standard deviation value does not exceed the average value / 10.

  In addition, even when the peel speed at which the cover tape 10 is peeled is 3000 mm / min, the properties of the seal layer 5 with respect to the PS carrier tape and the PC carrier tape are the peel-off strength when heat-sealed in an appropriate temperature range. The standard deviation value indicates almost the same and stable performance, and the same performance is obtained for other APET carrier tapes.

  FIG. 5 is a performance table of the peel-off strength of the cover tape 10 of this embodiment with respect to the type of the embossed carrier tape 11 (PS carrier tape and PC carrier tape), and FIG. 5A is a graph of the peel-off strength with respect to the heat seal temperature change. FIG. 5B is a graph of peel-off intensity with respect to environmental changes such as storage temperature.

  If the peel-off strength with respect to the change in the heat seal temperature shown in FIG. 5A is in the heat seal temperature region where the heat seal temperature is 140 ° C. or higher, there is no risk that the cover tape 10 is peeled off during transport from the embossed carrier tape 11. . Moreover, since the sealing layer 5 peels off at cohesive failure, reheat sealing is possible, and the difference in peel-off strength between normal heat sealing and reheat sealing is suppressed to within 0 to 10 g / mm. It has extremely recyclable characteristics.

  The peel-off strength with respect to the environmental change shown in FIG. 5 (b) can be obtained under different storage environment conditions (23 ° C. humidity 50% RH, 40 ° C. humidity 90%) from immediately after sealing (RA) to after storage time 720 hours. It shows a stable peel-off strength. When the conventional cover tape is stored at a high temperature, the cohesive force of the adhesive layer decreases due to changes over time, making it difficult to maintain the peel-off strength within an appropriate range. As shown in the figure, the tape 10 has excellent storage performance because the difference between the peel-off strength immediately after heat sealing and the peel-off strength due to aging under storage environment conditions is suppressed to 0.1 N or less.

  As described above, the characteristics of the chip-type electronic component packaging cover tape according to the present embodiment depend on the friction between the electronic component and the cover tape with respect to the type of the embossed carrier tape such as PS, PC, and APET to be used. Reduces static electricity or static electricity generated when the cover tape is peeled off, prevents tape strength from being reduced as the cover tape becomes thinner, prevents cover tape transparency from dropping even when stored at high temperatures, and peels off. It is possible to provide a chip-type electronic component packaging cover tape capable of maintaining the strength within an appropriate range.

  Further, it is possible to provide a chip-type electronic component packaging cover tape that can be used for high-speed peeling at a peel rate of 3000 mm / min.

  The structure of the cover tape 20 in which the peel-off strength is increased to 0.6 N when peel-off strength at low speed (300 mm / min) and high-speed (3000 mm / min) peeling is described.

  The ternary system phase diagram of the seal layer resin component shown in FIG. 6 is a mixed composition of the seal layer 5 reviewed in order to increase the peel-off strength. The acrylic resin is changed to an acrylic-modified polyolefin resin, and a styrene-based thermoplastic elastomer resin is used. A thermoplastic elastomer resin is selected, and the tackifying resin has the same resin composition as that of the same petroleum resin as in Example 1. By using a mixed composition in a preferable region shown in the center of this ternary phase diagram, it is possible to provide a cover tape 20 having a new configuration in which the peel-off strength is increased to 0.6N.

  From the ternary phase diagram of the seal layer 5 shown in FIG. 6, the ratio of the particularly preferred mixed composition of each resin is 40 to 90% by weight for the acrylic-modified polyolefin resin, 1 to 30% by weight for the tackifying resin, and styrene-based. A mixing ratio of 1 to 30% by weight of the thermoplastic elastomer resin is a preferred range. The mixing ratio of the metal oxide in the conductive fine powder added as an antistatic agent is preferably 30 to 55% by weight.

  Next, each resin constituting the seal layer 5 will be specifically described.

  In order to increase the peel-off strength, it is desirable that the acrylic-modified polyolefin resin has an acrylic resin component in the range of 20 to 80% by weight and a polyolefin resin component in the range of 20 to 80% by weight. For example, acrylic modified polyolefin resin A (acrylic resin component is 40% by weight, polyolefin resin component is 60% by weight, acrylic part TG is 40 to 50 ° C.) and acrylic modified polyolefin resin B (acrylic resin component is 70% by weight, polyolefin A mixture of a resin component of 30% by weight and an acrylic part TG of 139 ° C. is mixed with an acrylic modified polyolefin resin having a mixing ratio of 60% by weight of acrylic modified polyolefin resin A and 40% by weight of acrylic modified polyolefin resin B. Thus, the seal layer 5 having higher peel-off strength can be provided.

  The tackifying resin is preferably a petroleum hydrocarbon resin having a number average molecular weight of 400 to 2000 shown in Example 1, and is, for example, a copolymer of α-methylstyrene and styrene having a softening point of 120 ° C. 1120 etc. are used.

  As the thermoplastic elastomer, a typical olefinic elastomer (hereinafter referred to as olefin) is used as a thermoplastic elastomer resin that has excellent heat aging and weather resistance and has further flexibility. In particular, SEPS, A hydrogenated styrene-based thermoplastic elastomer resin containing 30 to 70% by weight of a styrene component such as SEEPS, SBS, SEBS, and SBBS is desirable. For example, Septon (registered trademark) 2104, which is capable of improving the physical properties of impact strength among hydrogenated SEPS resins and has excellent tensile elasticity with a flexible rubber property in a wide temperature range, is used. Hydrogenated SEPS resin has a styrene / ethylene / propylene ratio of 30/70 to 70/30% by weight. In the case of Septon (registered trademark) 2104, the styrene content is 65% by weight, and the MFR indicating fluidity is It is a block copolymer comprising a polystyrene hard block and a soft block of a polyolefin structure (hydrogenated polydiene) exhibiting the properties of a flexible rubber under conditions of 200 ° C. and 10 kg for 22 g / 10 minutes.

  FIG. 7 shows that the composition of the seal layer 5 of the cover tape 20 includes a petroleum resin which is a tackifying resin, an acrylic-modified polyolefin resin A (described as acrylic olefin A in the figure), and an acrylic-modified polyolefin resin B (in the figure, acrylic resin). It is composed of 10 kinds of sealant made by the presence or absence of mixing of acrylic elastomer resin represented by olefin and acrylic elastomer resin which realizes high peel-off strength by changing the mixing ratio with olefin B) It is a figure which shows the peel-off intensity | strength and basic performance according to composition of the sealing compound which comprises the sealing layer 5. FIG. It is the figure which showed the sealing agent SL2-1-SL2-5 which does not contain olefin, and SL2-6-SL2-10 of the sealing agent which contains 11.5 weight% of olefins, and the characteristic.

  FIG. 7A is a table showing the peel-off strength and basic performance of ten kinds of sealants SL2-1 to SL2-10 in which the composition such as the mixing ratio of the acrylic-modified polyolefin resin of the seal layer 5 is changed. Immediately after heat-sealing the cover tape 20 made of each sealant to the PC and PS embossed carrier tape 11 at 160 ° C., the peel speed is reduced from the embossed carrier tape 11 at a low speed (300 mm / min) and a high speed (3000 mm / min). It is a table | surface which shows the basic performance of the peel-off intensity | strength at the time of peeling, the surface resistance value of the sealing layer 5 which consists of each sealing agent, the haze value which shows transparency, and a total light transmittance.

  FIG. 7 (b) is a graph showing the mixing ratio of the ten types of sealants SL2-1 to SL2-10 by composition, and a certain amount of petroleum resin (tackifying resin) added to the composition of the seal layer resin component. And the optimum mixing ratio of acrylic modified polyolefin resin to olefin (thermoplastic elastomer resin) can be obtained.

  FIG. 8 is a graph for comparing the basic performances of the ten types of sealants SL2-1 to SL2-10 shown in FIG.

  FIG. 8A shows the results of measuring the peel-off strength according to the composition of the sealant at a low speed and a high peel speed. From the graph, an acrylic-modified polyolefin resin mixed with 20% by weight of a petroleum resin is an acrylic-modified polyolefin resin A. It can be seen that a high peel-off strength can be realized by changing the mixing ratio of the acryl-modified polyolefin resin B.

  However, in the case of the sealing agents SL2-1 to SL2-5 in which the olefin of the thermoplastic elastomer resin is not mixed, the peel-off strength varies depending on the type and peel speed of the embossed carrier tape 11 while having high peel-off strength. I can confirm that. In order to stabilize the fluctuation range of the peel-off strength, by comparing with the sealing agents SL2-6 to SL2-10 mixed with olefins having improved physical properties of impact strength and excellent tensile elasticity in a wide temperature range, You can see the difference.

  From the comparison results, by mixing 11.5% by weight of olefin such as styrene elastomer resin, the performance of acrylic modified polyolefin resin showing high peel-off strength is stabilized, and the peel-off strength at low speed and high speed peeling of the seal layer 5 is improved. The cover tape 20 having the seal layer 5 having a peel-off strength of 0.6 N can be provided stably without being affected by the type of the embossed carrier tape 11. In particular, sealing agents SL2-6 to SL2-9 (acrylic modified polyolefin resin A: 36.5 to 43.5% by weight, acrylic modified polyolefin resin B: 32.0 to 25.0% by weight, petroleum resin: 20.0% by weight %, Olefin: 11.5% by weight) has almost the same peel-off strength, and shows stable values with values of about 0.6 N at low speed and about 0.7 N at high speed.

FIG. 8B is a surface resistance value (Ω / □) representing the conductive characteristics of the seal layer 5, and in particular, the sealant of SL2-7 to SL2-9 mixed with 11.5 wt% of olefin is 9.2E8 (9 .2 × 10 ⁸ Ω / □), which is a value that sufficiently satisfies the range of 10E6 to 10E13Ω / □, which is a preferable surface resistance value of the seal layer 5.

  The haze value indicating the transparency of the sealing layer 5 in FIG. 8C shows a stable value of the sealing agents SL2-6 to SL2-9 mixed with olefin at around 12%, and the total light transmittance is also 80% or more. The required performance is fully satisfied.

  FIG. 9 is a performance table showing detailed test results of peel strength tests of sealants SL2-6 to SL2-10 mixed with olefin. From this performance table, it is stable when 11.5% by weight of olefin such as styrene-based thermoplastic elastomer resin which can improve the physical properties of impact strength and 20% by weight of petroleum resin and exhibits rubber-like properties in a wide temperature range. The optimum mixing ratio of the acrylic-modified polyolefin resin A and the acrylic-modified polyolefin resin B that provides the peel-off strength can be obtained.

  As described in Example 1, from the performance table, in the case of a cover tape having a peel-off strength of less than 0.4 N, there is a possibility that the electronic component may drop due to vibration during transportation, and the standard deviation value is an average. When the value exceeds / 10, vibration at the time of peeling increases, and there is a possibility of causing a jumping trouble that the electronic component jumps out of the storage pocket 11a.

  In the peel strength test according to the sealant composition of the cover tape 20 shown in FIG. 9, the temperature to be heat sealed to the PS carrier tape and PC carrier tape of the adherend is 160 ° C., the external environment is 28 ° C., and the humidity is 41%. About the package 12 immediately after heat sealing in Fig. 2, the peel off strength average value and standard deviation value at a high peeling speed of 3000 mm / min and a low speed of 300 mm / min are measured.

  From the test results, for the cover tape 20 heat-sealed to each embossed carrier tape 11, when a styrenic thermoplastic elastomer resin having a physical property improving function of impact strength and excellent tensile elasticity in a wide temperature range is mixed, By selecting a sealant in which the acrylic modified polyolefin resin A and the acrylic modified polyolefin resin B have an optimum mixing ratio, the cover tape 20 having the required stable peel-off strength can be provided.

  The performance of the seal layer 5 shown in FIG. 9 is that the average value of peel-off strength at high speed is 0.670 to 1.147, and particularly the values of the sealants SL2-7 to SL2-9 are 0.691 to 0.722. stable. Moreover, the average value of peel-off intensity | strength at low speed is 0.560-0.955N, and especially the value of sealing agent SL2-7-SL2-9 has shown the stable value at 0.583-0.593N.

  Therefore, acrylic modified polyolefin resin consisting of an optimal mixing ratio of acrylic modified polyolefin resin A and acrylic modified polyolefin resin B that achieves high peel-off strength, and styrene with excellent physical properties for improving impact strength and excellent tensile elasticity over a wide temperature range. Sealants SL2-7 to SL2-9 mixed with a thermoplastic elastomer resin (acrylic modified polyolefin resin A: 39.0 to 43.5% by weight, acrylic modified polyolefin resin B: 29.5 to 25.0% by weight , Petroleum resin: 20.0% by weight, olefin: 11.5% by weight) is stable enough to satisfy the required peel-off strength of 0.6 N without being influenced by the type of embossed carrier tape 11 to be heat-sealed. The standard deviation value that is the standard for jumping problems It is possible to provide a cover tape 20 of the sealing layer 5 having a performance not to exceed the values of / 10.

  Since the antistatic layer 1, the base material layer 2, the interlayer adhesive layer 3, and the intermediate layer 4 constituting the other cover tape 20 are the same as the cover tape 10 of the first embodiment, the description thereof is omitted.

  As described above, the cover tape shown in FIGS. 7, 8, and 9 is composed of an acrylic resin component and a polyolefin resin component with respect to a tackifier resin having a seal layer of 20 wt% and an olefin of 11.5 wt% as a thermoplastic elastomer. By mixing with an acrylic-modified polyolefin resin having an optimal mixing ratio, a cover tape having a stable performance that sufficiently satisfies the required peel-off strength of 0.6 N can be provided.

DESCRIPTION OF SYMBOLS 1 Antistatic layer 2 Base material layer 3 Interlayer adhesive layer 4 Intermediate layer 5 Conductive thermal adhesive layer (corresponding to seal layer)
10 Chip-type electronic component packaging cover tape 11 Embossed carrier tape 11a Storage pocket 12 Package 20 Chip-type electronic component packaging cover tape PC Polycarbonate PS Polystyrene PE Polyethylene PET Polyethylene terephthalate PP Polypropylene EVA Ethylene vinyl acetate

Claims (8)

A chip-type electronic component packaging cover tape that is heat-sealed to an embossed carrier tape in which a storage pocket for storing chip-type electronic components is formed,
An antistatic layer containing an antistatic agent, a biaxially stretched plastic film base material made of any one of polyethylene terephthalate, polypropylene, and nylon (registered trademark), an intermediate layer made of polyethylene, the base material, and the intermediate layer Having a multilayer structure formed by an adhesive layer for adhering and a seal layer thermally sealed to the embossed carrier tape,
The sealing layer is made of a resin mixture of a thermoplastic elastomer resin, a tackifier resin, and an acrylic resin, and conductive fine powder of metal oxide made of any one of tin oxide, zinc oxide, and indium oxide is dispersed in the resin mixture. A chip-type electronic component packaging cover tape characterized by the above.   The resin mixture constituting the sealing layer is dispersed in the thermoplastic elastomer resin in an amount of 14 to 49% by weight, the tackifying resin in an amount of 1 to 35% by weight, and the acrylic resin in an amount of 1 to 35% by weight. 2. The chip-type electronic component packaging cover tape according to claim 1, wherein the metal oxide is 30 to 55% by weight.   The thermoplastic elastomer resin is one or a mixture of styrene butadiene resin, styrene butadiene styrene block copolymer resin, and styrene ethylene butylene styrene block copolymer resin. 2. A cover tape for packaging electronic chip components according to 2. 4. The chip-type electronic component packaging cover tape according to claim 1, wherein the intermediate layer has a density of 0.8 to 0.909 g / cm ³ of polyethylene. 5. A chip-type electronic component packaging cover tape that is heat-sealed to an embossed carrier tape in which a storage pocket for storing chip-type electronic components is formed,
An antistatic layer containing an antistatic agent, a biaxially stretched plastic film base material made of any one of polyethylene terephthalate, polypropylene, and nylon (registered trademark), an intermediate layer made of polyethylene, the base material, and the intermediate layer Having a multilayer structure formed by an adhesive layer for adhering and a seal layer thermally sealed to the embossed carrier tape,
The sealing layer is made of a resin mixture of an acrylic-modified polyolefin resin, a tackifying resin, and a thermoplastic elastomer resin, and the resin mixture contains a metal oxide conductive fine powder made of any one of tin oxide, zinc oxide, and indium oxide. A cover tape for packaging chip-type electronic components, characterized in that is dispersed.   The resin mixture constituting the sealing layer is characterized in that the acrylic modified polyolefin resin is 40 to 90% by weight, the tackifying resin is 1 to 30% by weight, and the thermoplastic elastomer resin is 1 to 30% by weight. The chip-type electronic component packaging cover tape according to claim 5.   7. The chip-type electronic component packaging according to claim 5, wherein the acrylic-modified polyolefin resin has an acrylic resin component content in the range of 20 to 80% by weight and a polyolefin resin component in the range of 20 to 80% by weight. Cover tape.   The chip-type electronic component packaging cover tape according to any one of claims 5 to 7, wherein the thermoplastic elastomer resin is made of a styrene-based thermoplastic elastomer resin containing 30 to 70% by weight of a styrene component. .

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