JPWO2016143600A1 - Cover tape for packaging electronic parts and packaging for electronic parts - Google Patents

Abstract

The cover tape for packaging electronic parts of the present invention is provided on a surface opposite to the one surface of the base material layer, the sealant layer provided on the one surface side of the base material layer, and the base material layer. An antistatic layer, wherein the surface resistance value on the surface of the antistatic layer measured at 23 ° C. and 50% RH is R50, and the antistatic layer measured at 23 ° C. and 30% RH When the surface resistance value on the surface is R30, the value of R50 / R30 is 0.35 or more and 2.8 or less.

Description

  The present invention relates to an electronic component packaging cover tape and an electronic component packaging body.

  Conventionally, electronic parts such as transistors, diodes, capacitors, piezoelectric element registers, etc. have been formed on a carrier tape in which pockets capable of accommodating the electronic parts are continuously formed at the manufacturing site of electronic equipment, and the carrier tape. After being sealed in a package consisting of a cover tape to be sealed and heat-sealed, it is transported to a work area for surface mounting on an electronic circuit board or the like in a state of being wound on a paper or plastic reel. Yes. And after peeling the cover tape of the said package in the working area mentioned above, this electronic component is taken out from the said pocket formed in the carrier tape, and is surface-mounted on an electronic circuit board etc. The electronic components are required to be further miniaturized and highly mounted with recent miniaturization of electronic devices. Therefore, recent electronic components tend to be more susceptible to static electricity than ever.

  For example, Patent Document 1 discloses that a sealant layer is provided on a base material layer in order to suppress charge generated during peeling from a carrier tape, and the sealant layer includes a polyolefin resin and a polyether / polyolefin copolymer. A cover tape including is disclosed.

  Patent Document 2 discloses a cover tape in which the surface resistance value of the surface of the sealant layer is controlled so as to satisfy a specific condition in order to suppress charging generated by friction between the cover tape and the electronic component.

JP 2012-214252 A JP 2012-30897 A

However, in recent years, the technical level required for the viewpoint of countermeasures against static electricity of cover tapes is increasing.
As a result of various studies on the conventional cover tape, the present inventor has found the following problems.
When transporting a package containing electronic components while being wound around a reel, the surface where the carrier tape and the cover tape are bonded by vibration during transport, that is, the side opposite to the surface of the sealant layer in the cover tape Static electricity is generated by friction on the surface of the surface. Such static electricity may cause failure of the electronic components accommodated in the package or cause troubles such as sticking when mounting the substrate.
Based on such knowledge, the present inventor has found that there is room for improvement in terms of countermeasures against static electricity on the surface opposite to the surface of the sealant layer in the conventional cover tape.

  Therefore, the present invention provides an electronic component packaging cover tape having excellent frictional antistatic properties.

  As a result of intensive research in order to achieve the above-mentioned problems, the present inventor has obtained a base material layer, a sealant layer provided on one surface side of the base material layer, and a charge provided on the other surface of the base material layer. And a surface resistance value on the surface of the antistatic layer measured at 23 ° C. and 50% RH and a surface on the surface of the antistatic layer measured at 23 ° C. and 30% RH The present invention has been completed by obtaining the knowledge that the scale of the resistance value is effective as a design guideline for improving the antistatic properties accompanying peeling of the carrier tape.

According to the present invention, a base material layer;
A sealant layer provided on one surface side of the base material layer;
An antistatic layer provided on a surface opposite to the one surface of the base material layer;
A cover tape for packaging electronic parts having
The surface resistance value at the surface of the antistatic layer measured at 23 ° C. and 50% RH is defined as R _50, and the value of the surface resistance value at the surface of the antistatic layer measured at 23 ° C. and 30% RH is defined as R _30. Then, a cover tape for packaging electronic parts, in which the value of R ₅₀ / R ₃₀ is 0.35 or more and 2.8 or less, is provided.

  In addition, from a different viewpoint, the inventor has conducted extensive research to achieve the above-described problems, and as a result, the base material layer, the sealant layer provided on one surface side of the base material layer, and the other base material layer. In the cover tape for packaging electronic parts having the antistatic layer provided on the surface of the antistatic layer, the time when the absolute value of the frictional band voltage on the surface of the antistatic layer measured under different humidity conditions decays from 5 kV to 50 V (voltage decay) The present invention was completed by obtaining the knowledge that the measure of the rate of change in time) is effective as a design guideline for improving the antistatic properties accompanying peeling of the carrier tape.

According to the present invention, a base material layer;
A sealant layer provided on one surface side of the base material layer;
An antistatic layer provided on a surface opposite to the one surface of the base material layer;
A cover tape for packaging electronic parts having
With respect to the charging voltage decay time until the absolute value of the frictional charging voltage on the surface of the antistatic layer decays from 5 kV to 50 V, the value of the charging voltage decay time measured at 23 ° C. and 50% RH is S _50. Provided is a cover tape for packaging electronic parts in which the value of S ₅₀ / S ₃₀ is 0.7 or more and 1 or less, where S ₃₀ is the value of the voltage decay time measured at 0 ° C. and 30% RH.
Moreover, according to the present invention,
A component storage tape comprising a component tape for storing electronic components arranged side by side at a predetermined interval and a cover tape provided so as to cover the component storage portion formed on the carrier tape. Has been
The component storage tape can be wound in a reel shape,
The cover tape is an electronic component packaging body that is the electronic component packaging cover tape.

  ADVANTAGE OF THE INVENTION According to this invention, the cover tape for electronic component packaging excellent in friction antistatic property can be provided.

  The above-described object and other objects, features, and advantages will become more apparent from the preferred embodiments described below and the accompanying drawings.

It is a schematic sectional drawing which shows an example of the cover tape for electronic component packaging which concerns on this embodiment. It is a figure which shows an example of the state which sealed the cover tape for electronic component packaging which concerns on this embodiment to the carrier tape. It is a figure for demonstrating the measuring method of a friction voltage.

FIG. 1 is a schematic cross-sectional view showing an example of a cover tape for packaging electronic components according to the present embodiment.
As shown in FIG. 1, an electronic component packaging cover tape 10 (hereinafter also referred to as “cover tape”) according to the present embodiment is provided on the base layer 1 and one surface side of the base layer 1. The sealant layer 2 and the antistatic layer 3 provided on the surface of the base material layer 1 opposite to the one surface are provided. The cover tape 10 has a surface resistance value measured on the surface of the antistatic layer 3 measured at 23 ° C. and 50% RH as R ₅₀ and is measured on the surface of the antistatic layer 3 measured at 23 ° C. and 30% RH. When the surface resistance value is R ₃₀ , the value of R ₅₀ / R ₃₀ is 0.35 or more and 2.8 or less. Thereby, the cover tape excellent in the antistatic property accompanying peeling of a carrier tape is realizable. In addition, the said surface resistance value can be measured according to IEC61340.

FIG. 2 is a diagram illustrating an example of a state in which the electronic component packaging cover tape according to the present embodiment is sealed with a carrier tape.
First, the usage method of a cover tape is demonstrated with reference to FIG. As shown in FIG. 2, the cover tape 10 is used as a cover material for a carrier tape 20 in which concave pockets 21 are continuously provided in accordance with the shape of the electronic component. Specifically, the cover tape 10 is used by adhering (for example, heat sealing) to the surface of the carrier tape 20 so as to cover the entire opening of the pocket 21 of the carrier tape 20. In the following description, a structure obtained by bonding the cover tape 10 and the carrier tape 20 will be referred to as a package 100 for an electronic component.

  Actually, at the manufacturing site of electronic equipment, the package 100 for electronic parts is produced by the following procedure. First, an electronic component is accommodated in the pocket 21 of the carrier tape 20. Next, the cover tape 10 is adhered to the surface of the carrier tape 20 so as to cover the entire opening of the pocket 21 of the carrier tape 20, thereby obtaining a structure in which the electronic component is hermetically housed in the package 100. Can do. A structure containing such electronic components is conveyed to a work area where surface mounting is performed on an electronic circuit board or the like in a state where the package 100 is wound around a paper or plastic reel. As described above, when the electronic component is conveyed with the package 100 wound around the reel, the bottom surface 20 a of the carrier tape 20 is in contact (friction) with the surface 10 a of the cover tape 10.

In the present embodiment, the electronic component packaging body includes a carrier tape 20 in which component storage portions (pockets 21) for storing electronic components are arranged at predetermined intervals, and a component storage portion formed on the carrier tape 20. It is comprised with the component storage tape which consists of the cover tape 10 provided so that it might cover. This component storage tape can be wound into a reel.
In addition, the electronic component packaging cover tape (cover tape 10) of the present embodiment may have a sheet shape or a roll shape that can be wound into a reel.

Here, as a result of various studies, the present inventor has obtained the following knowledge. Specifically, when transporting a structure containing electronic components produced using a conventional cover tape, the surface where the carrier tape and the cover tape are bonded by vibration during transport, that is, the cover tape Static electricity is generated by friction on the surface opposite to the surface of the sealant layer. The static electricity generated by friction during transportation may cause the electronic components contained in the package to break down or cause problems such as sticking when mounted on the board.
From such knowledge, the present inventor has found that the conventional cover tape has room for improvement in terms of countermeasures against static electricity on the surface opposite to the surface of the sealant layer.
For example, a method of reducing the surface resistance value can be considered as a normal antistatic measure. However, even if the surface resistance value is lowered, triboelectric charging may occur. As a result of studies based on such knowledge, it has been considered that the generation of frictional charging can be suppressed by suppressing the charging in consideration of the working environment.

As a result of further investigations, most of the conventional cover tapes, in particular, have a large variation in surface resistance value on the surface of the antistatic layer due to a change in humidity in the working environment at the manufacturing site of the electronic equipment. Specifically, in the conventional cover tape, the fluctuation rate of the surface resistance value R ₅₀ and the surface resistance value R ₃₀ is larger than 2.8 times. From this, the inventor of the present application has obtained the knowledge that in the conventional cover tape, there is a high possibility that the charges derived from static electricity generated by friction move through moisture adhering to the surface of the antistatic layer. Thus, we focused on the characteristics including humidity change as a factor, and found new design guidelines.

That is, the cover tape according to the present embodiment has the surface resistance value R _{50 on} the surface of the antistatic layer measured at 23 ° C. and 50% RH and the antistatic layer measured at 23 ° C. and 30% RH as described above. The ratio of the surface resistance value R ₃₀ on the surface, the value of R ₅₀ / R ₃₀ satisfies a specific condition. By doing so, the static electricity generated by the contact between the bottom surface of the carrier tape and the surface of the cover tape due to vibration during transportation of the electronic component is stored in the package made of the carrier tape and the cover tape. It is possible to reduce the influence on the. For this reason, the electronic component may be electrostatically damaged due to the vibration that occurs when the electronic component is transported and the bottom surface of the carrier tape and the surface of the cover tape come into contact with each other, or troubles such as sticking when mounting the substrate. It is possible to suppress the occurrence of inconvenience.

In the cover tape according to the present embodiment, the lower limit value of R ₅₀ / R ₃₀ is, for example, preferably 0.35 or more, more preferably 0.4 or more, and further preferably 0.5 or more. . On the other hand, the upper limit value of R ₅₀ / R ₃₀ is, for example, preferably 2.8 or less, more preferably 2.5 or less, further preferably 2 or less, and still more preferably 1.5 or less. is there. By carrying out like this, the antistatic property accompanying peeling of a carrier tape can be improved further. In addition, most of the conventional typical cover tapes have a value of R ₅₀ / R ₃₀ of about 0.06. In particular, when the value of R ₅₀ / R ₃₀ is not more than the above upper limit value, a cover tape having excellent discharge characteristics can be realized even when static electricity is generated due to friction. In addition, since the surface resistance value change due to humidity change is small, a cover tape with excellent storage properties can be obtained. On the other hand, when the value of R ₅₀ / R ₃₀ is equal to or higher than the lower limit value, the cover tape and the electronic component are being transported even when the working environment in the electronic device manufacturing site is in a dry state of about 30 RH humidity. It is possible to realize a cover tape having excellent discharge characteristics such as static electricity generated by the friction between the carrier tape, static electricity generated when the cover tape is peeled off from the carrier tape, and static electricity generated from attached dust and contents. When the value of R ₅₀ / R ₃₀ satisfies a specific condition as in the cover tape according to the present embodiment, that is, the variation in the surface resistance value due to the humidity change of the working environment in the manufacturing site of the electronic device When the rate is small, since the charge derived from static electricity generated by friction can move through the material forming the antistatic layer, the moisture adhering to the surface of the antistatic layer can be passed through like the conventional cover tape. It is thought that it can suppress moving.

Further, the cover tape according to the present embodiment has a surface resistance value R _{50 on} the surface of the antistatic layer measured at 23 ° C. and 50% RH, and a surface resistance on the surface of the antistatic layer measured at 23 ° C. and 12% RH. the ratio between the value _{R 12,} the value of R 50 _{/ R 12} is, preferably, 0.1 to 10, still more preferably 0.125 to 8, and most preferably, 0.17 or more 6 It is as follows. This makes it possible to more strictly control the change in the surface resistance value of the antistatic layer on the cover tape as humidity changes in the work environment at the manufacturing site of electronic equipment. The cover tape can be further improved depending on the property.

From another point of view, the cover tape 10 according to the present embodiment has a time when the absolute value of the frictional voltage on the surface of the antistatic layer 3 decays from 5 kV to 50 V, that is, the voltage decay time is 23 ° C., When S ₅₀ is a value measured at 50% RH and S ₃₀ is a value measured at 23 ° C. and 30% RH, the value of S ₅₀ / S ₃₀ is 0.7 or more and 1 or less. By doing so, it is possible to realize a cover tape that is excellent in antistatic property due to peeling of the carrier tape. In the following description, it is assumed that the “charge voltage decay time S” refers to the time during which the absolute value of the friction charge voltage on the surface of the antistatic layer 3 decays from 5 kV to 50 V.

In particular, most of the conventional cover tapes have a large variation in the frictional voltage on the surface of the antistatic layer in accordance with the change in humidity of the working environment at the manufacturing site of electronic equipment. Specifically, in the conventional cover tape, the value of S ₅₀ / S ₃₀ calculated from the charging voltage decay time S ₅₀ and the charging voltage decay time S ₃₀ was less than 0.7. Therefore, the inventor of the present application can generate triboelectric charge by moving the charge derived from static electricity generated by friction through moisture adhering to the surface of the antistatic layer in the conventional cover tape. Based on the knowledge that it has high characteristics, we focused on the characteristics including humidity change as a factor, and found new design guidelines.

That is, the cover tape according to the present embodiment is calculated from the charged voltage decay time S ₅₀ measured at 23 ° C. and 50% RH and the charged voltage decay time S ₃₀ measured at 23 ° C. and 30% RH as described above. The value of S ₅₀ / S ₃₀ to be satisfied satisfies a specific condition. By doing so, the static electricity generated by the contact between the bottom surface of the carrier tape and the surface of the cover tape due to vibration during transportation of the electronic component is stored in the package made of the carrier tape and the cover tape. It is possible to reduce the influence on the. For this reason, the electronic component is electrostatically damaged due to the vibration generated when the electronic component is transported and the bottom surface of the carrier tape and the surface of the cover tape are in contact with each other, or troubles such as sticking when mounted on the board. It is possible to suppress the occurrence of inconvenience.

In the cover tape according to the present embodiment, the lower limit value of the above S ₅₀ / S ₃₀ is, for example, 0.7 or more, preferably 0.8 or more, and more preferably 0.9 or more. On the other hand, the upper limit value of S ₅₀ / S ₃₀ is not particularly limited, but may be 1 or less, for example. By carrying out like this, the antistatic property accompanying peeling of a carrier tape can be improved further. Specifically, when the value of S ₅₀ / S ₃₀ satisfies the above numerical range, even when the work environment at the electronic equipment manufacturing site is in a dry state with a humidity of about 30% RH, it is covered during transportation. Realize a cover tape with excellent discharge characteristics such as static electricity generated by friction between the tape and electronic components, static electricity generated when the cover tape is peeled off from the carrier tape, and static electricity generated from adhering dust and contents. be able to.

  Here, the frictional voltage on the surface of the antistatic layer, which is carried out to measure the charged voltage decay time S, can be measured, for example, by the following method. First, the surface of the antistatic layer in the cover tape and the surface of the object in contact with the surface of the antistatic layer in the cover tape such as a carrier tape are neutralized. Next, the surface of the antistatic layer in the cover tape is brought into contact with the surface of the object twice in one direction at a speed of about 100 mm / s and a distance of about 50 mm, for example, and a known surface electrometer is used. The frictional voltage is measured. As the frictional voltage according to the present embodiment, a result obtained by directly measuring the frictional voltage on the surface of the antistatic layer with a known surface potential meter may be employed, or the frictional voltage on the surface of the object may be used. You may employ | adopt the result computed from the result obtained by measuring a charged voltage.

In the cover tape according to the present embodiment, the value of the charging voltage decay time measured at 23 ° C. and 50% RH is S _50, and the value of the charging voltage decay time measured at 23 ° C. and 12% RH is S ₁₂ . Then, the value of S ₅₀ / S ₁₂ is preferably 0.2 or more and 1 or less, more preferably 0.4 or more and 1 or less, and most preferably 0.5 or more and 1 or less. In this way, it is possible to more strictly control the fluctuation of the triboelectric charge amount of the antistatic layer in the cover tape as the humidity of the work environment at the manufacturing site of the electronic equipment changes. The cover tape can be further improved depending on the property.

  The lower limit value of the total light transmittance of the cover tape according to this embodiment is preferably 80% or more, and more preferably 85% or more. In this way, in the package composed of the cover tape and the carrier tape, the necessary transparency is given to the extent that it is possible to inspect whether or not the electronic component is correctly accommodated in the pocket of the carrier tape. Can do. In other words, by making the total light transmittance of the base material layer equal to or higher than the above lower limit value, the electronic component housed in the package body composed of the cover tape and the carrier tape is visually confirmed from the outside of the package body. It becomes possible to do. Moreover, the upper limit of the total light transmittance of the cover tape is not particularly limited, but can be, for example, 100% or less. The total light transmittance of the cover tape can be measured according to JIS K7105 (1981).

In the cover tape according to the present embodiment, a sheet made of a material made of polystyrene is superposed on the surface of the antistatic layer of the cover tape, and the sheet is rubbed twice at a speed of 100 mm / s at an interval of 50 mm. After 5 seconds, the frictional voltage is measured at 23 ° C. and 50% RH. Although the friction withstand voltage of such a cover tape is not particularly limited, for example, it is preferably -1800 V or more and 1800 V or less, more preferably -1500 V or more and 1500 V or less, and further preferably -1000 V or more and 1000 V or less, More preferably, it is -800V or more and 800V or less. By doing so, the static electricity generated by the contact between the bottom surface of the carrier tape and the surface of the cover tape due to vibration during transportation of the electronic component is stored in the package made of the carrier tape and the cover tape. It is possible to further reduce the influence on the.
The surface of the antistatic layer in the cover tape and the surface of the object to be brought into contact with the surface of the antistatic layer in the cover tape such as a carrier tape are neutralized. Next, the surface of the antistatic layer in the cover tape is brought into contact with the surface of the object twice in one direction, and the frictional voltage is measured using a known surface potential meter. As the frictional voltage according to the present embodiment, a result obtained by directly measuring the frictional voltage on the surface of the antistatic layer with a known surface potential meter may be employed, or the frictional voltage on the surface of the object may be used. You may employ | adopt the result computed from the result obtained by measuring a charged voltage.

  Although the width | variety of the cover tape which concerns on this embodiment is not specifically limited, For example, 2 mm or more and 100 mm or less may be sufficient, Preferably it may be 2 mm or more and 80 mm or less, More preferably, it is good also as 2 mm or more and 50 mm or less.

  Hereinafter, the configuration of each layer forming the cover tape according to the present embodiment will be described in detail.

<Base material layer 1>
The material constituting the base material layer can be used when making a cover tape by laminating an antistatic layer or sealant layer on the base material layer, when bonding the cover tape to the carrier tape, or when using the cover tape. As long as it has sufficient mechanical strength to withstand the stress applied from the outside, etc., and heat resistance to withstand the heat history applied when the cover tape is bonded to the carrier tape Good. Moreover, the form of the material which comprises a base material layer is although it does not specifically limit, From a viewpoint with which a process is easy, a film form may be sufficient.

  Specific examples of the material constituting the base material layer include, for example, polyester resins, polyamide resins, polyolefin resins, polyacrylate resins, polymethacrylate resins, polyimide resins, polycarbonate resins, ABS resins, and the like. Can be mentioned. Among these, from the viewpoint of improving the mechanical strength of the cover tape, a polyester resin is preferable, and polyethylene terephthalate is more preferable. Further, from the viewpoint of improving the mechanical strength and flexibility of the cover tape, nylon 6 may be used as a material constituting the base material layer. In addition, you may contain a lubricant in the material which comprises a base material layer. These may be used alone or in combination of two or more.

  The base material layer may be formed of a single layer film containing the above-described material, or may be formed using a multilayer film containing the above-described material in each layer. Moreover, as a form of the film used for forming the base material layer, an unstretched film or a film stretched in a uniaxial direction or a biaxial direction may be used. From the viewpoint of improving the strength, a film stretched in a uniaxial direction or a biaxial direction may be used.

  The thickness of the base material layer may be, for example, 9 μm or more and 25 μm or less, and preferably 9 μm or more and 16 μm or less. When the thickness of the base material layer is not more than the above upper limit value, the cover tape is not too high in rigidity, and even if a torsional stress is applied to the carrier tape after sealing, the cover tape is Following the deformation, it is possible to suppress peeling. In addition, when the thickness of the base material layer is equal to or higher than the above upper limit value, the mechanical strength of the cover tape can be improved, so even when the cover tape is peeled off from the carrier tape at a high speed, It can suppress that a cover tape breaks.

  The lower limit value of the total light transmittance of the base material layer is, for example, preferably 80% or more, and preferably 85% or more. In this way, in the package composed of the cover tape and the carrier tape, the necessary transparency is given to the extent that it is possible to inspect whether or not the electronic component is correctly accommodated in the pocket of the carrier tape. Can do. In other words, by making the total light transmittance of the base material layer equal to or higher than the above lower limit value, the electronic component housed in the package body composed of the cover tape and the carrier tape is visually confirmed from the outside of the package body. It becomes possible to do. Although the upper limit of the total light transmittance of a base material layer is not specifically limited, For example, it can be 100% or less. The total light transmittance of the base material layer can be measured according to JIS K7105 (1981).

<Sealant layer 2>
In the cover tape according to this embodiment, the sealant layer is a layer provided on the surface of the base material layer opposite to the surface on which the antistatic layer is provided. The surface of the sealant layer comes into contact with the carrier tape when the cover tape is used by the method described above. In this embodiment, the multi-layer structure including an antistatic layer, a base material layer, and a sealant layer provides a balance between adhesion and peelability to a carrier tape, and an electronic component packaging cover tape having excellent antistatic properties. Can be realized.

  As a material constituting the sealant layer, for example, a material containing a thermoplastic resin such as an acrylic resin or a polyester resin and an antistatic agent can be used. Specific examples of such antistatic agents include metal fillers such as tin oxide, zinc oxide, titanium oxide, and smectite, surfactants having a structure such as polyoxyethylene alkylamine, quaternary ammonium, and alkyl sulfonate, polyoxyethylene Polymer type antistatic agent, ionic liquid, polypyrrole, poly (3,4-ethylenedioxythiophene polyacetylene, polyaniline, etc. incorporating structures such as alkylamine, quaternary ammonium, alkyl sulfonate, polyether etc. Examples thereof include conductive polymers composed of these derivatives, one kind selected from the group consisting of carbon, or a mixture thereof, and examples of the carbon include various carbons such as carbon black, white carbon, carbon fiber, and carbon tube. A filler having the following shape may be used, and these may be used alone or in combination of two or more.

  The material constituting the sealant layer includes oxide particles mainly composed of silicon, magnesium or calcium, inorganic particles such as silica and talc, polyethylene particles, polyacrylate particles, and polystyrene from the viewpoint of preventing blocking that occurs during transportation. 1 type selected from the group which consists of organic particles, such as particles, or these alloys may be contained.

  The thickness of the sealant layer may be, for example, 1 μm or more and 15 μm or less, preferably 1 μm or more and 10 μm or less, more preferably 1 μm or more and 5 μm, from the viewpoint of improving the balance between adhesion to the carrier tape and peelability. It is good also as follows.

The surface resistance value of the sealant layer may be set to, for example, 10 ⁴ Ω or more and 10 ¹¹ Ω or less under the conditions of 23 ° C. and 50 RH% from the viewpoint of efficiently discharging static electricity generated by various factors to the outside. It may be from 10 ⁵ Ω to 10 ¹⁰ Ω, and more preferably from 10 ⁵ Ω to 10 ⁹ Ω. The surface resistance value can be measured according to IEC61340.

<Antistatic layer 3>
In the cover tape according to the present embodiment, the antistatic layer is a layer provided on the surface of the base material layer opposite to the surface on which the sealant layer is provided. As described above, the surface of the antistatic layer has a possibility of coming into contact with the bottom surface of the carrier tape when the electronic component is accommodated and transported in a package made of the carrier tape and the cover tape.

  Hereinafter, materials for forming the antistatic layer will be described.

  The material forming the antistatic layer is, for example, a charged column compared to a material forming an object that contacts the surface of the antistatic layer when an electronic component such as a material forming the bottom surface of the carrier tape is accommodated and transported. It is preferable to include a “positive compound” located on the positive side in FIG. 5 and a “negative compound” located on the negative side in the charged column as compared with the material forming the object. By doing so, it is possible to suppress the generation of static electricity due to friction when the surface of the antistatic layer comes into contact with the object. Although the detailed mechanism is not clear, when the surface of the antistatic layer comes into contact with an object, the positive compound contained in the material forming the antistatic layer is charged positively, while the negative compound is negatively charged Therefore, it is considered that it can be electrically neutralized in the antistatic layer.

  Here, as a result of investigation by the present inventor, a specific material is used as an object in contact with the surface of the antistatic layer, and by using this as a reference, charging is performed when a positive compound and a negative compound are used in combination. It has been found that the antistatic property of the protective layer can be stably obtained. As a result of further investigation, by adopting cotton cloth (cotton 100%) as a reference, the influence of changing the positive / negative of the charge depending on the frictional material can be avoided, so the combined use of the positive compound and the negative compound of this embodiment It was found that the antistatic property of the resulting antistatic layer can be stably obtained. Examples of the method for measuring the positive and negative charge amounts include a method in which the surface of a resin sheet or the surface of a film coated on the sheet is rubbed with a cotton cloth (cotton 100%) and then measured with a surface potential meter. In this case, for example, a surface potentiometer such as 3M Static Sensor 718 can be used.

  The positive compound of the present embodiment may be a compound that is positively charged with respect to the cotton cloth. For example, styrene acrylic copolymer, ester acrylic copolymer, acrylic resin, vinyl alcohol, formaldehyde-modified nylon, aziridinyl compound, epoxy And positive binder resins such as compounds and carbodiimide compounds. These may be used alone or in combination of two or more.

  In addition, as a positive compound, for example, a material that forms an object that comes into contact with the surface of the antistatic layer when containing and transporting an electronic component, such as a material that forms the bottom surface of the carrier tape, contains polystyrene or the like Therefore, an aziridinyl compound and its ring-opening compound may be used. The aziridinyl compound generally refers to a compound having an aziridinyl group, and specific examples thereof include N, N′-hexamethylene-1,6-bis (1-aziridycarboxamide), N, N′-diphenylmethane. -4,4'-bis (1-aziridinecarboxamide), trimethylolpropane-tri-β-aziridinylpropionate), N, N'-toluene-2,4-bis (1-aziridinecarboxyamide) , Triethylenemelamine, trimethylolpropane-tri-β (2-methylaziridine) propionate, bisisophthaloyl-1-methylaziridine, tri-1-aziridinylphosphine oxide, tris-1-methylaziridine A phosphine oxide etc. are mentioned. Further, as the aziridinyl compound, commercially available products such as Chemitite PZ-33 and DZ-22E manufactured by Nippon Shokubai Co., Ltd. can be used. In addition, the ring-opening compound of an aziridinyl compound refers to the compound in the state which the aziridinyl group in an aziridinyl compound was ring-opened.

  The content of the positive compound described above is preferably 0.2% by weight or more and 98% by weight or less, and preferably 0.5% by weight or more and 90% by weight or less with respect to the total amount of the material forming the antistatic layer. And more preferred. By doing so, the physical strength of the coating film is increased and the antistatic agent slips off due to contact.

  As a negative compound of this embodiment, what is necessary is just a compound negatively charged with respect to cotton cloth, For example, negative binder resins, such as a fluororesin and a polyester compound, are mentioned. These may be used alone or in combination of two or more.

  In addition, as a negative compound, the material that forms an object that comes into contact with the surface of the antistatic layer when containing and transporting electronic components such as the material that forms the bottom surface of the carrier tape often contains polystyrene or the like. Therefore, an ester compound may be used. The ester compound refers to a compound formed by combining an organic acid or inorganic acid and an alcohol by a dehydration reaction. Specific examples thereof include polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, and derivatives thereof. Is mentioned.

  The content of the negative compound described above is preferably 0.2% by weight or more and 98% by weight or less, and preferably 0.5% by weight or more and 90% by weight or less with respect to the total amount of the material forming the antistatic layer. And more preferred. By doing so, the physical strength of the coating film is increased and the antistatic agent slips off due to contact.

  Here, as a result of investigation by the present inventors, it was found that the antistatic property of the antistatic layer can be improved by using the positive compound and the negative compound in combination. Furthermore, the antistatic layer in which the positive compound and the negative compound are sufficiently dispersed can appropriately control the characteristics including the surface resistance value and the humidity change such as the charging voltage decay time as a factor. It has been found that prevention can be realized. Although the detailed mechanism is not clear, since the triboelectric charge generated by friction can be neutralized by the positive compound and the negative compound, it is considered that the characteristics including humidity change can be appropriately controlled.

In addition, it was found that the blending amount of the positive compound and the negative compound is determined based on the solid content, thereby facilitating the control of the frictional antistatic property by the combined use thereof.
Specifically, the lower limit value of the solid content of the negative compound is, for example, 50% by weight or more with respect to the total value of 100% by weight of the solid content of the positive compound and the solid content of the negative compound. Preferably, 60% by weight or more is preferable, and 70% by weight or more is more preferable. The upper limit value of the solid content of the negative compound is not particularly limited. For example, the upper limit value is 99% by weight or less with respect to 100% by weight of the total solid content of the positive compound and the solid content of the negative compound. Alternatively, it may be 95% by weight or less, or 90% by weight or less. Thus, by achieving a balance between the positive compound and the negative compound, the production stability of the antistatic layer having excellent frictional antistatic properties can be improved.

The upper limit of the surface resistance value of the antistatic layer is, for example, preferably 10 ¹¹ Ω or less, more preferably 10 ¹⁰ Ω or less, further preferably 10 ⁹ Ω or less, and 10 ⁷ Ω or less, under the conditions of 23 ° C. and 15 RH%. Is more preferable. Thereby, antistatic property can be improved. The lower limit of the surface resistance value of the antistatic layer is not particularly limited under the conditions of 23 ° C. and 15 RH%, but may be, for example, 10 ³ Ω or more, and preferably 10 ⁴ Ω or more. The surface resistance value can be measured according to IEC61340.

  The material forming the antistatic layer preferably contains a conductive polymer from the viewpoint of reducing the surface resistance value of the antistatic layer and suppressing the generation of static electricity due to friction. Specific examples of such a conductive polymer include polyaniline, polypyrrole and the like, and among them, a polyethylenedioxythiophene / polystyrene sulfonic acid (PEDOT / PSS) based compound can be suitably used. These may be used alone or in combination of two or more.

  The material for forming the antistatic layer preferably contains a surfactant from the viewpoint of improving the wettability and leveling properties when forming the antistatic layer. Such a surfactant may be a low molecular surfactant or a high molecular surfactant, but a surfactant having a fluorine alkyl structure can be suitably used. These may be used alone or in combination of two or more.

  The frictional voltage of the antistatic layer is, for example, preferably from −1800 V to 1800 V, more preferably from −1500 V to 1500 V, and even more preferably from −1000 V to 1000 V under the conditions of 23 ° C. and 50% RH. Or less, more preferably from −800 V to 800 V, and most preferably from −500 V to 500 V. Further, the absolute value of the frictional voltage of the antistatic layer is, for example, preferably 1800 V or less, more preferably 1500 V or less, and further preferably 1000 V or less under the conditions of 23 ° C. and 50% RH. More preferably, it is 800 V or less, and most preferably 500 V or less. In this way, the electronic component may be electrostatically damaged due to the vibration that occurs when the electronic component is transported and the bottom surface of the carrier tape and the surface of the cover tape come into contact with each other, or trouble occurs when mounting the board. It is possible to suppress the occurrence of inconvenience.

  Further, the lower limit value of the film thickness of the antistatic layer of the present embodiment is not particularly limited, but may be, for example, 1 nm or more, preferably 10 nm or more, and more preferably 20 nm or more. Thereby, the mechanical strength of the antistatic layer can be improved. The upper limit value of the film thickness of the antistatic layer is not particularly limited, but may be, for example, 5 μm or less, preferably 4 μm or less, and more preferably 3 μm or less. Thereby, the softness | flexibility of the whole cover tape by which the antistatic layer was laminated | stacked can be improved. Moreover, the integration density of the cover tape per volume of the accommodation space can be increased.

<Other layers>
The cover tape which concerns on this embodiment may provide an intermediate | middle layer (not shown) between a base material layer and a sealant layer. By doing so, the cushioning property of the entire cover tape can be improved, and the adhesion with the carrier tape to be bonded can be improved.

  Examples of the material forming the intermediate layer include olefin resins, styrene resins, and cyclic olefin resins. Among these, an olefin resin may be used from the viewpoint of improving the adhesion with the carrier tape to be bonded. These may be used alone or in combination of two or more.

  The thickness of the intermediate layer may be, for example, 10 μm or more and 30 μm or less, and preferably 15 μm or more and 25 μm or less, from the viewpoint of improving the adhesion to the carrier tape that is the object to be bonded.

  In the cover tape according to the present embodiment, an adhesive layer may be provided between the base material layer and the sealant layer or between the base material layer and the antistatic layer. By doing so, the mechanical strength of the cover tape can be improved.

  Resin is contained in the material which forms the contact bonding layer mentioned above. Specific examples of such resins include urethane-based dry laminate adhesive resins, anchor coat adhesive resins, and the like, and generally a combination of a polyester composition such as polyester polyol or polyether polyol and an isocyanate compound, or polybutadiene. Polyimine resin or the like can be used.

  Next, materials for forming an object that comes into contact with the surface of the antistatic layer when the electronic component is accommodated and transported will be described. As described above, the object includes the bottom surface of the carrier tape, etc., but has the possibility of coming into contact with the surface of the antistatic layer when accommodating and transporting the electronic component or mounting the electronic component. If it is a thing, it will not be limited. Specific examples of the material forming the object include materials for forming carrier tapes such as polystyrene, polyethylene terephthalate, and polycarbonate, polyethylene, rubber (material processed from natural rubber, synthetic rubber, etc.), and the like. .

Next, the manufacturing method of the cover tape which concerns on this embodiment is demonstrated.
The manufacturing method of the cover tape in this embodiment is different from the conventional manufacturing method, and it is necessary to highly control the manufacturing conditions described later. That is, for the first time by a manufacturing method that highly controls various factors relating to the following two conditions, the surface resistance value R _{50 on} the surface of the antistatic layer measured at 23 ° C. and 50% RH, and at 23 ° C. and 30% RH It is possible to obtain a cover tape in which the measured ratio of the surface resistance value R _{30 on} the surface of the antistatic layer and the value of R ₅₀ / R ₃₀ satisfies the above-mentioned specific conditions.
(1) Composition of resin material for forming antistatic layer (2) Combination of material for forming antistatic layer and material for forming base material layer

However, the cover tape in the present embodiment adopts various specific manufacturing conditions such as temperature setting of the manufacturing apparatus, on the premise that various factors related to the above two conditions are highly controlled. Can do. In other words, the cover tape in the present embodiment can be manufactured by adopting a known method except for highly controlling various factors related to the above two conditions. Among these, for example, a positively charged positive compound and a negatively charged negative compound are used in combination with the antistatic layer, and these are well dispersed. It is mentioned as an element for appropriately controlling the characteristics included in the factors and making R ₅₀ , R ₃₀ , and R ₅₀ / R ₃₀ within a desired numerical range. Hereinafter, an example of a cover tape manufacturing method will be described on the assumption that various factors related to the above two conditions are highly controlled.
First, an antistatic layer is formed by applying a predetermined material to one surface of the base material layer and drying it. Next, a sealant layer is laminated by extrusion lamination on the surface of the base material layer opposite to the surface on which the antistatic layer is formed. Thus, the cover tape which concerns on this embodiment can be produced. In addition, after forming a sheet | seat of a sealant layer by an extrusion method, you may laminate | stack the sheet | seat obtained on the surface on the opposite side to the surface in which the antistatic layer of the base material layer was formed.

Moreover, the manufacturing method of the cover tape which concerns on this embodiment in another viewpoint is demonstrated.
The manufacturing method of the cover tape in this embodiment is different from the conventional manufacturing method, and it is necessary to highly control the manufacturing conditions described later. That is, until the absolute value of the friction band voltage on the surface of the antistatic layer measured at 23 ° C. and 50% RH is attenuated from 5 kV to 50 V for the first time by a manufacturing method that highly controls various factors related to the following two conditions. charged voltage decay time _S 50, 23 ° C., the charged voltage decay time _S 30 until the absolute value of the frictional electrification voltage at the surface of the antistatic layer was measured at RH 30% decreased to 50V from _{5kV, S} 50 _/ S ₃₀ A cover tape satisfying the above-mentioned specific condition can be obtained.
(1) Composition of resin material for forming antistatic layer (2) Combination of material for forming antistatic layer and material for forming base material layer

However, the cover tape in the present embodiment adopts various specific manufacturing conditions such as temperature setting of the manufacturing apparatus, on the premise that various factors related to the above two conditions are highly controlled. Can do. In other words, the cover tape in the present embodiment can be manufactured by adopting a known method except for highly controlling various factors related to the above two conditions. Among these, for example, a positively charged positive compound and a negatively charged negative compound are used in combination, and these are well dispersed. Is controlled as appropriate, and the above S ₅₀ , S ₃₀ , and S ₅₀ / S ₃₀ are included as elements in a desired numerical range. Hereinafter, an example of a cover tape manufacturing method will be described on the assumption that various factors related to the above two conditions are highly controlled.
First, an antistatic layer is formed by applying a predetermined material to one surface of the base material layer and drying it. Next, a sealant layer is laminated by extrusion lamination on the surface of the base material layer opposite to the surface on which the antistatic layer is formed. In this manner, the cover tape according to this embodiment can be manufactured. In addition, after forming a sheet | seat of a sealant layer by an extrusion method, you may laminate | stack the sheet | seat obtained on the surface on the opposite side to the surface in which the antistatic layer of the base material layer was formed.

  Further, when forming the above-described intermediate layer, the intermediate layer may be laminated by extrusion lamination on the surface of the base material layer opposite to the surface on which the antistatic layer is formed. After the sheet is formed by the extrusion method, the obtained sheet may be laminated on the surface of the base material layer opposite to the surface on which the antistatic layer is formed.

  Moreover, what is necessary is just to apply | coat the material of an adhesive layer to the target surface by the conventionally well-known coating method, when forming the adhesive layer mentioned above.

  As mentioned above, although embodiment of this invention was described, these are illustrations of this invention and various structures other than the above are also employable.

  Hereinafter, although an example and a comparative example explain the present invention, the present invention is not limited to these.

[Example A]
In Example A and Comparative Example A, the respective raw material components used for the production of the antistatic layer and the sealant layer are shown below.

<Antistatic layer>
(Antistatic agent)
Antistatic agent A1: Conductive polymer containing polyethylenedioxythiophene / polystyrene sulfonic acid (PEDOT / PSS) based compound (manufactured by Heraeus, CLEVIOS P)
Antistatic agent A2: tin dioxide (manufactured by Diary Catalysts)
Antistatic agent A3: cationic low-molecular surfactant (manufactured by NOF Corporation, Elegan 264-30)
Antistatic agent A4: cationic polymer surfactant (manufactured by Taisei Fine Chemical Co., Ltd., ACRYT 1SX-1090)

(Diluted solvent)
Diluting solvent A1: isopropyl alcohol: water = 1: 1
Diluting solvent A2: toluene: methyl ethyl ketone = 1: 1
Diluting solvent A3: isopropyl alcohol

(Binder resin)
Positive binder resin A1: Carbodiimide (Nisshinbo Chemical Co., Ltd., Carbodilite V-02-L2)
Positive binder resin A2: Acrylic resin (Aron S-1001 manufactured by Toa Gosei Co., Ltd.)
Negative binder resin A3: water-soluble polyester resin (manufactured by Kyoyo Chemical Co., Ltd., plus coat Z760)
Negative binder resin A4: water-soluble polyester resin (manufactured by Kyoyo Chemical Co., Ltd., plus coat Z565)

(Surfactant)
Surfactant A1: BYK-3440 manufactured by Big Chemie Japan
Surfactant A2: manufactured by San Nopco, SN Dispersant 9228

<Sealant layer>
Styrene- (meth) methyl acrylate copolymer (manufactured by Nippon Steel Chemical Co., Ltd., Estyrene MS-600. Hereinafter also referred to as “St-MMA”)
-Ethylene-methyl acrylate copolymer (Mitsui-Dupont Polychemical Co., Ltd., Elvalloy AC 1820. Hereinafter, also referred to as "EMA".)
Polyether / polyolefin copolymer (manufactured by Sanyo Chemical Industries, Pelestat 212; hereinafter also referred to as “PEG-PP”)

<Manufacture of cover tape according to Example A>
First, a biaxially stretched polyester film (Toyobo Co., Ltd. product: E5102) having a thickness of 16 μm was prepared as a base material layer. The total light transmittance of the obtained base material layer was 87.7%.

Next, a material for forming the antistatic layer was prepared by the following method. The composition of each reagent is as shown in Table 1.
The antistatic agent was stirred for 30 seconds while adding a diluent solvent. Next, in order to improve the substrate adhesion and dispersion stability, the binder resin and the surfactant were added, followed by stirring for 30 seconds. In this way, a material for forming a liquid antistatic layer was prepared.

  Subsequently, the material (in liquid form) for forming the obtained antistatic layer was applied to one surface of the base material layer using a bar coater or a gravure coater so that the wet film thickness was 4 μm. Then, the antistatic layer was formed into a film by making it dry at 100 degreeC.

  Next, the sealant layer was laminated | stacked by the extrusion lamination method with respect to the surface on the opposite side to the surface which formed the antistatic layer in the base material layer. As a material for forming such a sealant layer, a resin composition comprising 15 parts by weight of St-MMA, 65 parts by weight of EMA and 20 parts by weight of PEG-PP was used. The thickness of the sealant layer was 5 μm.

  The cover tape which concerns on Example A1, A2 was produced with the above method. The width of the obtained cover tape was 8 mm.

<Manufacture of cover tape according to Comparative Example A>
For the antistatic layer, as shown in Table 1, a cover tape was prepared in the same manner as in Example A using a mixed solution of an antistatic agent and a diluting solvent obtained without adding a binder resin and a surfactant. .

  The following evaluation was performed using the cover tapes of Example A and Comparative Example A.

<Evaluation method>
Surface resistance value on the surface of the antistatic layer: The surface resistance value on the surface of the antistatic layer under the three humidity conditions of 50 RH%, 30 RH% and 12 RH% at a temperature of 23 ° C. was measured according to IEC61340. . The unit is Ω.

Total light transmittance: The total light transmittance of the cover tape was measured according to JIS K7105 (1981). The unit is%.

Friction voltage: The friction voltage measured at 23 ° C. and 50% RH was measured by the method described in (1) to (7) below with reference to FIG. The unit is V.

(1) On the pedestal 30 with a wheel whose surface resistance value is less than 1.0 × 10 ¹¹ Ω, a plate-like rubber body 40 having a surface resistance value of 1.0 × 10 ¹³ Ω or more was installed. . Next, two insulators 50 were installed on the rubber body 40 at a predetermined interval. The insulator 50 is a quadrangular prism having a thickness of 10 mm or more and a surface resistance value of 1.0 × 10 ¹³ Ω or more. Next, a polystyrene sheet 70 (manufactured by Electrochemical Co., Ltd., Clearen CST2401) was fixed using a double-sided tape so as to be in contact with both of the two insulators 50. In addition, the said polystyrene-type sheet | seat 70 is a friction target object made to contact with each cover tape in the measurement mentioned later. Further, the wheeled pedestal 30 was always in a grounded state.

(2) The polystyrene sheet 70 was neutralized using an ionizer (BLH-H manufactured by Kasuga Denki Co., Ltd.).

(3) The pedestal 30 with wheels is moved and moved so that the polystyrene sheet 70 is arranged under the measurement probe 60 provided in the surface potentiometer (manufactured by TREK, MODEL 370). I confirmed. In addition, the space | interval of the polystyrene-type sheet | seat 70 and the measurement probe 60 was 1-2 mm.

(4) The cover tape 10 was wound around a rod-shaped support 80 having a surface resistance value of less than 1.0 × 10 ⁹ Ω so that the antistatic layer became the surface layer. The support 80 is made of a conductor made of a carbon-kneaded film in order to reduce the influence of charging when it is supported by hand. The cover tape 10 was also neutralized by the same method as that for the polystyrene-based sheet 70.

(5) The wheeled pedestal 30 was moved, the polystyrene sheet 70 was moved from below the measurement probe 60, and the surface of the polystyrene sheet 70 was rubbed by the antistatic layer in the cover tape 10 wound around the support 80. At this time, the friction due to the antistatic layer in the cover tape 10 is rubbed twice at a speed of 100 mm / s and at an interval of 50 mm in one direction in the longitudinal direction with respect to the polystyrene-based sheet 70 with the pedestal 30 with the wheel fixed. It was to do.

(6) Within 5 seconds from the friction between the antistatic layer in the cover tape 10 and the polystyrene sheet 70, the polystyrene sheet 70 was moved under the measurement probe 60, and the frictional voltage was measured using an ionizer. .

(7) From the value of the friction voltage on the surface of the obtained polystyrene-based sheet 70, the friction voltage on the surface of the antistatic layer in the cover tape 10 was calculated. Note that, as described above, the polystyrene sheet 70 and the cover tape 10 used for the measurement of the frictional voltage are those having a charged voltage of 0 V, which was removed before the friction test. Therefore, when the friction band voltage on the surface of the polystyrene-based sheet 70 is 100V, the friction band voltage on the surface of the antistatic layer in the cover tape 10 is calculated as 100V (= 0V−100V).

  The evaluation results regarding the above evaluation items are shown in Table 1 below together with the composition of the antistatic layer.

The cover tapes of Examples A1 and A2 were both excellent in antistatic properties associated with the peeling of the carrier tape, as well as the balance between the adhesiveness to the carrier tape and the peeling property. In particular, the cover tapes of Examples A1 and A2 include both a positive binder resin and a negative binder resin, and the antistatic layer is formed using a material including a conductive polymer. It was hard to generate. On the other hand, the cover tapes of Comparative Examples A1 and A2 have humidity dependency in terms of antistatic properties accompanying peeling of the carrier tape, and did not satisfy the required level.
The obtained cover tape and a polystyrene carrier tape were rubbed, and the absolute value of the charged voltage on the surface of the cover tape was measured. As a result, it was found that Examples A1 and A2 have good anti-friction properties. On the other hand, it was found that Comparative Examples A1 and A2 were inferior in frictional antistatic properties.
The obtained cover tape was heat-sealed on a carrier tape, and then wound on a seal to obtain a package for electronic parts wound up in a reel shape.

[Example B]
In Example B and Comparative Example B, the respective raw material components used for producing the antistatic layer and the sealant layer are shown below.

<Antistatic layer>
(Antistatic agent)
Antistatic agent B1: Conductive polymer containing polyethylenedioxythiophene / polystyrene sulfonic acid (PEDOT / PSS) based compound (manufactured by Heraeus, CLEVIOS P)
Antistatic agent B2: tin dioxide (manufactured by Diary Catalysts)
Antistatic agent B3: cationic low molecular surfactant (manufactured by NOF Corporation, Elegan 264-30)
Antistatic agent B4: cationic polymer surfactant (manufactured by Taisei Fine Chemical Co., Ltd., ACRYT 1SX-1090)

(Diluted solvent)
Diluting solvent B1: isopropyl alcohol: water = 1: 1
Diluting solvent B2: toluene: methyl ethyl ketone = 1: 1
Diluting solvent B3: isopropyl alcohol

(Binder resin)
-Positive binder resin B1: Carbodiimide (Nisshinbo Chemical Co., Ltd., Carbodilite V-02-L2)
Positive binder resin B2: Acrylic resin (Aron S-1001 manufactured by Toa Gosei Co., Ltd.)
Negative binder resin B3: water-soluble polyester resin (manufactured by Kyoyo Chemical Co., Ltd., plus coat Z760)
Negative binder resin B4: water-soluble polyester resin (manufactured by Kyoyo Chemical Co., Ltd., plus coat Z565)

(Surfactant)
Surfactant B1: BYK-3440 manufactured by BYK Japan
Surfactant B2: manufactured by San Nopco, SN Dispersant 9228

<Sealant layer>
Styrene- (meth) methyl acrylate copolymer (manufactured by Nippon Steel Chemical Co., Ltd., Estyrene MS-600. Hereinafter also referred to as “St-MMA”)
-Ethylene-methyl acrylate copolymer (Mitsui-Dupont Polychemical Co., Ltd., Elvalloy AC 1820. Hereinafter, also referred to as "EMA".)
Polyether / polyolefin copolymer (manufactured by Sanyo Chemical Industries, Pelestat 212; hereinafter also referred to as “PEG-PP”)

<Manufacture of cover tape according to Example B>
First, a biaxially stretched polyester film (Toyobo Co., Ltd. product: E5102) having a thickness of 16 μm was prepared as a base material layer. The total light transmittance of the obtained base material layer was 87.7%.

Next, a material for forming the antistatic layer was prepared by the following method. The composition of each reagent is as shown in Table 2.
The antistatic agent was stirred for 30 seconds while adding a diluent solvent. Next, in order to improve the substrate adhesion and dispersion stability, the binder resin and the surfactant were added, followed by stirring for 30 seconds. In this way, a material for forming a liquid antistatic layer was prepared.

  Subsequently, the material (in liquid form) forming the obtained antistatic layer was applied to one surface of the base material layer using a bar coater or a gravure coater so that the wet thickness was 4 μm. Then, the antistatic layer was formed into a film by making it dry at 100 degreeC.

  Next, the sealant layer was laminated | stacked by the extrusion lamination method with respect to the surface on the opposite side to the surface which formed the antistatic layer in the base material layer. As a material for forming such a sealant layer, a resin composition comprising 15 parts by weight of St-MMA, 65 parts by weight of EMA and 20 parts by weight of PEG-PP was used. The thickness of the sealant layer was 5 μm.

  By the above method, cover tapes according to Examples B1 and B2 were produced. The width of the obtained cover tape was 8 mm.

<Manufacture of cover tape according to Comparative Example B>
Cover tape in the same manner as in Examples 1 and 2 except that a mixed solution of an antistatic agent and a diluting solvent obtained without adding a binder resin and a surfactant was used as a material for forming the antistatic layer. Was made.

  The following evaluations were performed using the cover tapes of Example B and Comparative Example B.

<Evaluation method>
・ Attenuation time of charged voltage: the absolute value of the friction voltage on the surface of the antistatic layer measured using the method described later under three humidity conditions of 50% RH, 30% RH and 12% RH at a temperature of 23 ° C. The time until the value decayed from 5 kV to 50 V was measured. The unit is seconds (s). Furthermore, in Table 1 below, the time until the value of the friction band voltage is attenuated from +5 kV to +50 V is S +, and the time until the value of the friction band voltage is attenuated from −5 kV to −50 V is S−. did.

Friction band voltage: The friction band voltage measured at 23 ° C. and 50% RH was measured by the same method as in Example A with reference to FIG. The unit is V.

Total light transmittance: The total light transmittance of the cover tape was measured according to JIS K7105 (1981). The unit is%.

  The evaluation results regarding the above evaluation items are shown in Table 2 below together with the composition of the antistatic layer.

The cover tapes of Examples B1 and B2 were both excellent in antistatic properties accompanying the peeling of the carrier tape, as well as the balance between the adhesiveness to the carrier tape and the peeling property. In particular, the cover tapes of Examples 1B and B2 include both a positive binder resin and a negative binder resin, and the antistatic layer is formed using a material containing a conductive polymer. It was hard to generate. On the other hand, the cover tapes of Comparative Examples B1 and B2 have humidity dependency in terms of antistatic properties accompanying peeling of the carrier tape, and did not satisfy the required level.
The obtained cover tape and a polystyrene carrier tape were rubbed, and the absolute value of the charged voltage on the surface of the cover tape was measured. As a result, it was found that Examples B1 and B2 have good anti-friction properties. On the other hand, it was found that Comparative Examples B1 and B2 were inferior in frictional antistatic properties.
The obtained cover tape was heat-sealed on a carrier tape, and then wound on a seal to obtain a package for electronic parts wound up in a reel shape.

[Example C]
In Example C, the raw material components used for the production of the antistatic layer are shown below.

(Binder resin)
-Positive compound C1: Acrylate ester copolymer resin (manufactured by Toa Gosei Co., Ltd., Jurimer FC-80)
Negative compound C1: water-soluble polyester resin (manufactured by Kyoyo Chemical Co., Ltd., plus coat Z565)

(Antistatic agent)
Antistatic agent C1: Conductive polymer containing polyethylenedioxythiophene / polystyrene sulfonic acid (PEDOT / PSS) -based compound (Orgacon ICP1010, manufactured by Japan Agfa Materials)

(Other)
Diluent C1: Isopropyl alcohol Diluent C2: Water Neutralizer C1: Triethylamine (Wako Pure Chemical Industries, Ltd. TEA)
Surfactant C1: BYK-3440 manufactured by Big Chemie Japan

<Production of Cover Tape According to Example C>
First, a biaxially stretched polyester film (Toyobo Co., Ltd. product: E5102) having a thickness of 16 μm was prepared as a base material layer. The total light transmittance of the obtained base material layer was 87.7%.

Next, a material for forming the antistatic layer was prepared by the following method. In addition, the composition of the materials forming the antistatic layer is as shown in Table 3.
The mixture was stirred for 30 seconds while adding a neutralizing agent and a diluting solvent to the antistatic agent. Next, in order to improve the substrate adhesion and dispersion stability, the binder resin and the surfactant were added, followed by stirring for 30 seconds. In this way, a material for forming a liquid antistatic layer was prepared.

  Subsequently, the material (in liquid form) forming the obtained antistatic layer was applied to one surface of the base material layer using a bar coater or a gravure coater so that the wet thickness was 4 μm. Then, the antistatic layer was formed into a film by making it dry at 100 degreeC.

  Next, the sealant layer was laminated | stacked by the extrusion lamination method with respect to the surface on the opposite side to the surface which formed the antistatic layer in the base material layer. As a material for forming such a sealant layer, a resin composition comprising 15 parts by weight of St-MMA, 65 parts by weight of EMA and 20 parts by weight of PEG-PP was used. The thickness of the sealant layer was 5 μm.

  The cover tape which concerns on Example C1-C3 was produced by the above method. The widths of the obtained cover tapes were all 8 mm.

  The following evaluation was performed using each cover tape of Example C.

-Surface resistance value: The surface resistance value on the surface of the antistatic layer was measured according to IEC61340 under three humidity conditions of 50 RH%, 30 RH% and 12 RH% at a temperature of 23 ° C. The unit is Ω.

Total light transmittance: The total light transmittance of the cover tape was measured according to JIS K7105 (1981). The unit is%.

The obtained cover tape and a polystyrene carrier tape were rubbed, and the absolute value of the charged voltage on the surface of the cover tape was measured. As a result, it was found that Examples C1 to C3 have good anti-friction properties.
The obtained cover tape was heat-sealed on a carrier tape, and then wound on a seal to obtain a package for electronic parts wound up in a reel shape.
The cover tapes of Examples C1 to C3 were all excellent in antistatic properties against friction generated during transportation and the like and antistatic properties accompanying peeling of the carrier tape.

[Example D]
In Example D, the respective raw material components used for the production of the antistatic layer and the sealant layer are shown below.

<Antistatic layer>
(Binder resin)
Positive compound D1: Acrylic ester copolymer resin (Arakawa Chemical Industries, Ltd .: Aracoat CL910)
Negative compound D1: water-soluble polyester resin (manufactured by Kyoyo Chemical Co., Ltd., plus coat Z565)

(Antistatic agent)
Antistatic agent D1: Conductive polymer containing polyethylenedioxythiophene / polystyrene sulfonic acid (PEDOT / PSS) -based compound (Arakawa Chemical Co., Ltd., Aracoat ACS332)

(Other)
-Diluent D1: Isopropyl alcohol-Diluent D2: Water-Surfactant D1: Arakawa ACS347 manufactured by Arakawa Chemical Co., Ltd.

<Sealant layer>
Styrene- (meth) methyl acrylate copolymer (manufactured by Nippon Steel Chemical Co., Ltd., Estyrene MS-600. Hereinafter also referred to as “St-MMA”)
-Ethylene-methyl acrylate copolymer (Mitsui-Dupont Polychemical Co., Ltd., Elvalloy AC 1820. Hereinafter, also referred to as "EMA".)
Polyether / polyolefin copolymer (manufactured by Sanyo Chemical Industries, Pelestat 212; hereinafter also referred to as “PEG-PP”)

<Preparation of Cover Tape for Electronic Component Packaging According to Example D>
First, a biaxially stretched polyester film (Toyobo Co., Ltd. product: E5102) having a thickness of 25 μm was prepared as a base material layer. The total light transmittance of the obtained base material layer was 87.7%.

Next, a material for forming the antistatic layer was prepared by the following method. The composition of the material forming the antistatic layer is as shown in Table 4.
It stirred for 30 seconds, adding the diluting solvent which mix | blended isopropyl alcohol and water with the predetermined ratio with respect to the antistatic agent. Next, in order to improve the substrate adhesion and dispersion stability, the binder resin and the surfactant were added, followed by stirring for 30 seconds. In this way, a material for forming a liquid antistatic layer was prepared.

  Subsequently, the material (in liquid form) forming the obtained antistatic layer was applied to one surface of the base material layer using a bar coater or a gravure coater so that the wet thickness was 4 μm. Thereafter, an antistatic layer was formed by drying at 100 ° C. for 1 minute.

  Next, the sealant layer was laminated | stacked by the extrusion lamination method with respect to the surface on the opposite side to the surface which formed the antistatic layer in the base material layer. As a material for forming such a sealant layer, a resin composition comprising 15 parts by weight of St-MMA, 65 parts by weight of EMA and 20 parts by weight of PEG-PP was used. The thickness of the sealant layer was 5 μm.

  By the above method, the electronic component packaging cover tape according to Examples D1 to D4 was produced. The widths of the obtained cover tapes were all 8 mm.

  The following evaluation was performed using each cover tape of Example D.

-Surface resistance value: The surface resistance value on the surface of the antistatic layer was measured according to IEC61340 under three humidity conditions of 50 RH%, 30 RH% and 12 RH% at a temperature of 23 ° C. The unit is Ω.

Total light transmittance: The total light transmittance of the cover tape was measured according to JIS K7105 (1981). The unit is%.

The obtained cover tape and a polystyrene carrier tape were rubbed, and the absolute value of the charged voltage on the surface of the cover tape was measured. As a result, it was found that Examples D1 to D4 had good anti-friction properties.
The obtained cover tape was heat-sealed on a carrier tape, and then wound on a seal to obtain a package for electronic parts wound up in a reel shape.
The cover tapes of Examples D1 to D4 were all excellent in antistatic properties against friction generated during transportation or the like and antistatic properties accompanying peeling of the carrier tape, regardless of the type of material constituting the carrier tape. It was a thing.

  This application claims priority based on Japanese Patent Application No. 2015-046796 filed on Mar. 10, 2015 and Japanese Patent Application No. 2015-074142 filed on Apr. 1, 2015. , The entire disclosure of which is incorporated herein.

Claims (17)

A base material layer;
A sealant layer provided on one surface side of the base material layer;
An antistatic layer provided on a surface opposite to the one surface of the base material layer;
A cover tape for packaging electronic parts having
The surface resistance value at the surface of the antistatic layer measured at 23 ° C. and 50% RH is defined as R _50, and the value of the surface resistance value at the surface of the antistatic layer measured at 23 ° C. and 30% RH is defined as R _30. The cover tape for packaging electronic parts, wherein the value of R ₅₀ / R ₃₀ is 0.35 or more and 2.8 or less. The electronic component packaging cover tape according to claim 1,
The surface resistance value at the surface of the antistatic layer measured at 23 ° C. and 50% RH is defined as R _50, and the surface resistance value at the surface of the antistatic layer measured at 23 ° C. and 12% RH is defined as R _12. The cover tape for packaging electronic parts, wherein the value of R ₅₀ / R ₁₂ is 0.1 or more and 10 or less. A base material layer;
A sealant layer provided on one surface side of the base material layer;
An antistatic layer provided on a surface opposite to the one surface of the base material layer;
A cover tape for packaging electronic parts having
With respect to the charging voltage decay time until the absolute value of the frictional charging voltage on the surface of the antistatic layer decays from 5 kV to 50 V, the value of the charging voltage decay time measured at 23 ° C. and 50% RH is S _50. A cover tape for packaging electronic parts, wherein the value of S ₅₀ / S ₃₀ is 0.7 or more and 1 or less, where S ₃₀ is the value of the voltage decay time measured at 0 ° C. and 30% RH. The electronic component packaging cover tape according to claim 3,
When the value of the charging voltage decay time measured at 23 ° C. and 50% RH is S ₅₀ and the value of the charging voltage decay time measured at 23 ° C. and 12% RH is S ₁₂ , S ₅₀ / S ₁₂ An electronic component packaging cover tape having a value of 0.2 or more and 1 or less. The electronic component packaging cover tape according to any one of claims 1 to 4,
An electronic component packaging cover tape, wherein the total light transmittance of the electronic component packaging cover tape is 80% or more. The electronic component packaging cover tape according to any one of claims 1 to 5,
A sheet made of a material made of polystyrene is superposed on the surface of the antistatic layer of the cover tape for packaging electronic parts, and the sheet is superimposed twice on the surface at a speed of 100 mm / s and at an interval of 50 mm. A cover tape for packaging electronic parts, wherein a frictional voltage measured at 23 ° C. and 50% RH is −1800 V or more and 1800 V or less 5 seconds after the friction. The electronic component packaging cover tape according to any one of claims 1 to 6,
A cover tape for packaging electronic parts, wherein the antistatic layer contains an ester compound. The electronic component packaging cover tape according to any one of claims 1 to 7,
A cover tape for packaging electronic parts, wherein the antistatic layer comprises a positively charged positive compound and a negatively charged negative compound. The electronic component packaging cover tape according to claim 8,
The electronic component packaging cover, wherein the solid content of the negative compound is 50% by weight or more with respect to a total value of 100% by weight of the solid content of the positive compound and the solid content of the negative compound tape. The electronic component packaging cover tape according to any one of claims 1 to 9,
A cover tape for packaging electronic parts, wherein the antistatic layer contains a conductive polymer. It is a cover tape for electronic parts packaging according to any one of claims 1 to 10,
A cover tape for packaging electronic parts, wherein the antistatic layer contains a surfactant. The electronic component packaging cover tape according to any one of claims 1 to 11,
The cover tape for electronic component packaging whose film thickness of the said antistatic layer is 1 micrometer or more and 20 micrometers or less. The electronic component packaging cover tape according to any one of claims 1 to 12,
A cover tape for packaging electronic parts, wherein the sealant layer has a surface resistance value of 10 ⁵ Ω or more and 10 ¹¹ Ω or less under the conditions of 23 ° C. and 50 RH%. The electronic component packaging cover tape according to any one of claims 1 to 13,
The cover tape for electronic component packaging whose film thickness of the said sealant layer is 1 micrometer or more and 15 micrometers or less. The electronic component packaging cover tape according to any one of claims 1 to 14,
A cover tape for packaging electronic parts, wherein the substrate layer has a total light transmittance of 80% or more. The electronic component packaging cover tape according to any one of claims 1 to 15,
A cover tape for packaging electronic parts, wherein the width of the cover tape for packaging electronic parts is 2 mm or more and 100 mm or less. A component storage tape comprising a component tape for storing electronic components arranged side by side at a predetermined interval and a cover tape provided so as to cover the component storage portion formed on the carrier tape. Has been
The component storage tape can be wound in a reel shape,
The said cover tape is a package for electronic components which is the cover tape for electronic component packaging of any one of Claim 1 to 16.

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