JP2017128699A - Resin composition and cover tape - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a resin composition which constitutes a sealant layer of a cover tape and exhibits high antistatic ability and high peel strength in a well-balanced manner.SOLUTION: The resin composition of the present invention constitutes a sealant layer 2 of a cover tape 10 for sealing a carrier tape having recesses capable of storing electronic components. The resin composition contains (A) a polyolefin resin, (B) an antistatic agent, and (C) a polystyrene resin and/or (D) a (meth)acrylate polymer. The antistatic agent (B) contains an antistatic agent containing lithium ions. The content of the polyolefin resin (A) is 20 pts.mass or more based on 100 pts.mass of the resin composition.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a resin composition and a cover tape.

  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.

In such a series of steps, the following characteristics are required for a cover tape used as a packaging material for electronic components.
That is, an antistatic ability as a cover tape is required so that the electronic component can be prevented from jumping out of the pocket due to peeling electrification that can occur when the cover tape is peeled off, and the electronic component is not charged.

  In relation to this, for example, techniques disclosed in Patent Documents 1 to 6 are known. These documents disclose resin compositions, films, sheets, and the like that exhibit antistatic ability, and there is also a suggestion that such resin compositions, films, sheets, and the like can be developed for various uses.

JP 2010-196052 A JP 2010-196053 A JP 2011-026555 A JP 2011-162661 A JP 2011-252040 A JP 2013-0776010 A

Here, in producing the cover tape as described above, there is a situation that not only the antistatic property as the sealant layer is further improved, but also the adhesiveness with the carrier tape must be appropriately realized.
On the other hand, in Patent Document 1, the antistatic ability is expressed by a polylactic acid resin, in Patent Document 2 is an acrylic resin, and in Patent Documents 3 to 5, the knowledge that a polystyrene resin exhibits an antistatic ability Resin compositions and the like have been produced based on this, but if these resins are added excessively, there is a concern that the peel strength of the cover tape may be reduced. In these documents, the surface resistivity of the resin composition is evaluated, but most of them are not satisfactory for use in a cover tape for electronic parts.
Patent Document 6 discloses a polystyrene-based resin film characterized by containing a specific polymer antistatic agent, thereby reducing the amount of the polymer antistatic agent used. It is shown that it can be achieved. However, the actually disclosed resin composition is insufficient in terms of peel strength to form a sealant layer for a cover tape.
That is, in this technical field, as a resin composition constituting the sealant layer of the cover tape, a resin composition that has a high balance between high antistatic ability and high peel strength has been desired.

  Then, this invention makes it a subject to provide the resin composition which expresses high antistatic ability and high peeling strength with sufficient balance as a resin composition which comprises the sealant layer of a cover tape.

According to the present invention,
A resin composition constituting a sealant layer of a cover tape for sealing a carrier tape having a recess capable of accommodating an electronic component,
The resin composition is
(A) a polyolefin-based resin;
(B) an antistatic agent;
(C) polystyrene resin and / or (D) (meth) acrylic acid ester polymer;
Including
The antistatic agent (B) includes an antistatic agent containing lithium ions,
A resin composition in which the content of the (A) polyolefin-based resin with respect to 100 parts by mass of the resin composition is 20 parts by mass or more is provided.

Moreover, according to the present invention,
A cover tape for sealing a carrier tape having a recess capable of accommodating an electronic component,
A cover tape comprising a sealant layer composed of the above resin composition is provided.

  ADVANTAGE OF THE INVENTION According to this invention, the resin composition which expresses high antistatic ability and high peeling strength with sufficient balance can be provided as a resin composition which comprises the sealant layer of a cover tape.

It is a figure 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 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.

Hereinafter, the present invention will be described with reference to the accompanying drawings based on embodiments. In all the drawings, the same reference numerals are given to the same components, and the description will be omitted as appropriate.
In addition, the components and elements described in the embodiments can be appropriately combined as long as the effects of the invention are not impaired.

The resin composition of this embodiment is shown below.
A resin composition constituting a sealant layer of a cover tape for sealing a carrier tape having a recess capable of accommodating an electronic component,
The resin composition is
(A) a polyolefin-based resin;
(B) an antistatic agent;
(C) polystyrene resin and / or (D) (meth) acrylic acid ester polymer;
Including
The antistatic agent (B) includes an antistatic agent containing lithium ions,
The resin composition whose content of the said (A) polyolefin-type resin with respect to 100 mass parts of said resin compositions is 20 mass parts or more.

[Cover tape]
First, a cover tape to which the resin composition of this embodiment is applied will be described.
FIG. 1 is a cross-sectional view showing an example of an electronic component packaging cover tape according to the present embodiment.
As shown in FIG. 1, an electronic component packaging cover tape 10 (hereinafter also simply referred to as “cover tape”) according to the present embodiment is provided on a base layer 1 and one surface side of the base layer 1. The sealant layer 2 is provided. Here, this sealant layer 2 is comprised by the resin composition which concerns on this embodiment.
Hereinafter, each layer which comprises the cover tape 10 for electronic component packaging of this embodiment is demonstrated.

<Base material layer 1>
The material constituting the base material layer 1 is a cover tape when the sealant layer 2 is laminated on the base material layer 1 to produce a cover tape, and the carrier tape 20 (see FIG. 3, the same applies hereinafter). When the cover tape 10 is bonded, it can withstand the mechanical history that can withstand the stress applied from the outside when the cover tape 10 is used, and the thermal history applied when the cover tape 10 is bonded to the carrier tape 20. Those having heat resistance to such an extent that they can be used are preferable. The form of the material constituting the base material layer is not particularly limited, but it is preferably processed into a film form from the viewpoint of easy processing.

  Specific examples of the material constituting the base material layer 1 include polyester resins, polyamide resins, polyolefin resins, polyacrylate resins, polymethacrylate resins, polyimide resins, polycarbonate resins, ABS resins, and the like. It is done. Among these, polyester resins are preferable from the viewpoint of improving the mechanical strength of the cover tape 10. Further, nylon 6 may be used as a material constituting the base material layer 1 from the viewpoint of improving the mechanical strength and flexibility of the cover tape 10. In addition, the material constituting the base material layer 1 may contain a lubricant.

  The base material layer 1 may be formed by a single layer film including the above-described material, or may be formed using a multilayer film including the above-described material in each layer. Moreover, as a form of the film used in order to form the base material layer 1, an unstretched film may be sufficient, and the film extended | stretched to the uniaxial direction or the biaxial direction may be sufficient. From the viewpoint of improving mechanical strength, a film stretched in a uniaxial direction or a biaxial direction is preferable.

  The thickness of the base material layer 1 is preferably 5 μm or more, more preferably 10 μm or more. Moreover, the thickness of the base material layer 1 is preferably 50 μm or less, and more preferably 40 μm or less. When the thickness of the base material layer 1 is less than or equal to the above upper limit value, the cover tape 10 does not become too rigid, and the cover tape 10 can be applied even when a torsional stress is applied to the carrier tape 20 after sealing. Can follow the deformation of the carrier tape 20 and can be prevented from peeling off. Moreover, since the mechanical strength of the cover tape 10 can be made favorable when the thickness of the base material layer 1 is not less than the above lower limit value, the cover tape 10 is peeled off from the carrier tape 20 at a high speed. Even if it exists, it can suppress that the cover tape 10 fractures | ruptures.

  The total light transmittance of the base material layer 1 is preferably 80% or more, and more preferably 85% or more. By doing so, in the package 100 (see FIG. 3, the same applies hereinafter) composed of the cover tape 10 and the carrier tape 20 described later, the electronic components are correctly placed in the pockets 21 (refer to FIG. 3; the same applies hereinafter) of the carrier tape 20. Necessary transparency can be imparted to such an extent that it can be inspected whether or not it is contained. In other words, by setting the total light transmittance of the base material layer 1 to be equal to or higher than the above lower limit value, the electronic component accommodated in the package 100 composed of the cover tape 10 and the carrier tape 20 can be placed outside the package 100. It becomes possible to visually confirm from. In addition, the total light transmittance of the base material layer 1 can be measured according to JIS K7105 (1981).

<Sealant layer 2>
In the electronic component packaging cover tape 10 according to this embodiment, the sealant layer 2 is a layer provided on one surface of the base material layer 1. The surface of the sealant layer 2 comes into contact with the carrier tape 20.

In this embodiment, the sealant layer 2 includes (A) a polyolefin resin and (B) an antistatic agent, and (C) a polystyrene resin and (D) a (meth) acrylic ester polymer. It is comprised with the resin composition containing at least one of them.
Hereinafter, each component which comprises this sealant layer 2 is demonstrated.

((A) polyolefin resin)
The resin composition constituting the sealant layer 2 of the present embodiment includes (A) a polyolefin-based resin.
This (A) polyolefin resin is a resin having units derived from an α-olefin such as ethylene, propylene, and butene, and can be appropriately selected from known materials and used.

In this embodiment, it is preferable to use an ethylene copolymer as the (A) polyolefin resin.
Examples of the ethylene copolymer include resins such as an ethylene-vinyl acetate copolymer, an ethylene-aliphatic unsaturated carboxylic acid copolymer, an ethylene-aliphatic unsaturated carboxylic acid ester copolymer, and an ionomer.
By using such a resin, the peel strength with respect to the carrier tape 20 can be made suitable.

  Examples of the ethylene-aliphatic unsaturated carboxylic acid copolymer include an ethylene-acrylic acid copolymer and an ethylene-methacrylic acid copolymer.

  Examples of the ethylene-aliphatic unsaturated carboxylic acid ester copolymer include an ethylene-acrylic acid ester copolymer and an ethylene-methacrylic acid ester copolymer. As acrylic acid ester and methacrylic acid ester, ester with C1-C8 alcohol, such as methanol and ethanol, is used suitably. Among the ethylene-aliphatic unsaturated carboxylic acid ester copolymers, an ethylene-methyl acrylate copolymer, an ethylene-ethyl acrylate copolymer, or an ethylene-methyl methacrylate copolymer is preferable from the viewpoint of versatility. .

Among the above resins, the ethylene copolymer is preferably an ethylene-vinyl acetate copolymer or an ethylene-aliphatic unsaturated carboxylic acid ester copolymer from the viewpoint of adhesion to a carrier tape substrate and cost. .
In this embodiment, the ethylene-vinyl acetate copolymer is a copolymer of at least ethylene and vinyl acetate, and the ethylene-aliphatic unsaturated carboxylic acid ester copolymer is a copolymer of at least ethylene and an aliphatic unsaturated carboxylic acid ester. In some cases, other monomers may be further copolymerized.

From the viewpoint of peel strength, the ethylene-vinyl acetate copolymer preferably has a vinyl acetate ratio of 10% by mass or more and 35% by mass or less, and 15% by mass or more, in all monomers constituting the copolymer. More preferably, it is 30 mass% or less. Thereby, peeling strength with a carrier tape can be made suitable.
The ethylene-aliphatic unsaturated carboxylic acid ester copolymer has a ratio of the aliphatic unsaturated carboxylic acid ester in the total monomers constituting the copolymer of 10% by mass or more and 35% by mass from the viewpoint of peel strength. % Or less, more preferably 15% by mass or more and 30% by mass or less. Thereby, peeling strength with a carrier tape can be made suitable.

  Note that. These copolymers may be multi-component copolymers obtained by copolymerizing three or more monomers. Examples of the multi-component copolymer include a copolymer obtained by copolymerizing at least three types of monomers selected from ethylene, an aliphatic unsaturated carboxylic acid ester, and an acid anhydride.

  From the viewpoint of peel strength, the (A) polyolefin resin has a melt flow rate value (hereinafter sometimes referred to as “MFR”) measured in accordance with JIS-K-7210 (190 ° C., 2. 16 kg) is preferably from 0.1 g to 100 g, more preferably from 1 g to 50 g. Thereby, the peeling strength with the carrier tape 20 can be made suitable.

In the present embodiment, the content of the (A) polyolefin-based resin with respect to 100 parts by mass of the resin composition constituting the sealant layer 2 is 20 parts by mass or more, preferably 30 parts by mass or more, more preferably 45 parts by mass. That's it.
Thus, the moderate peel strength as the sealant layer 2 can be achieved by setting the content of the (A) polyolefin-based resin.
In the present embodiment, the content of the (A) polyolefin-based resin with respect to 100 parts by mass of the resin composition constituting the sealant layer 2 is preferably 85 parts by mass or less, more preferably 80 parts by mass or less. More preferably, it is 78 mass parts or less.
Thus, by setting the content of the (A) polyolefin-based resin, it is possible to realize a higher level of antistatic performance.

((B) antistatic agent)
The resin composition constituting the sealant layer 2 of the present embodiment includes (B) an antistatic agent. Here, in the present embodiment, as the (B) antistatic agent, one containing lithium ions is used.
In the present embodiment, by using the antistatic agent containing lithium ions as described above, it is possible to realize an even better antistatic ability as the sealant layer 2.

More specifically, as this (B) antistatic agent, a polymer type antistatic agent in which lithium ions are present in the resin can be used. Thereby, the outstanding antistatic performance is exhibited stably stably.
Lithium ions can be contained in the antistatic agent in the form of, for example, a lithium salt. Examples of the lithium salt include lithium chloride, lithium fluoride, lithium bromide, lithium iodide, lithium perchlorate, lithium acetate, lithium fluorosulfonate, lithium methanesulfonate, lithium trifluoromethanesulfonate, and pentafluoroethanesulfonic acid. Lithium etc. are mentioned.

  In addition, the lithium ion contained in (B) antistatic agent can be confirmed by a metal element amount measurement. In the present embodiment, the amount of lithium ions contained in the antistatic agent is preferably set to, for example, 50 μg / g or more (50 ppm or more).

In the present embodiment, the antistatic agent (B) can be used in combination with a known antistatic agent in addition to the above-described antistatic agent containing lithium ions.
Examples of the antistatic agent include polyamide-based copolymers such as polyether ester amide, block polymers of polyolefin and polyether, polymers composed of polyethylene ether and glycol, carboxylic acid group-containing polymers such as potassium ionomer, and quaternary ammonium bases. Examples thereof include metal-containing copolymers, metal fillers such as tin oxide, zinc oxide, and titanium oxide, and thiophene-based conductive polymers such as polyethylenedioxythiophene / polystyrene sulfonic acid (PEDOT / PSS).
These antistatic agents preferably have a thermal decomposition temperature of 120 ° C. or higher in order to prevent deterioration due to high temperatures during extrusion lamination or heat sealing.

In the present embodiment, the content of the antistatic agent (B) with respect to 100 parts by mass of the resin composition constituting the sealant layer 2 is, for example, 5 parts by mass or more, preferably 8 parts by mass or more, and more preferably 10 parts. More than part by mass.
Thus, by setting the content of the antistatic agent (B), the sealant layer 2 can exhibit an appropriate antistatic ability.
In this embodiment, the content of the antistatic agent (B) with respect to 100 parts by mass of the resin composition constituting the sealant layer 2 is preferably 25 parts by mass or less, more preferably 20 parts by mass or less, More preferably, it is 18 mass parts or less, Most preferably, it is 16 mass parts or less.
In general, since the antistatic agent (B) is expensive, setting the content of the antistatic agent in this way can contribute to cost reduction in the production of the cover tape.

In this embodiment, the ratio of (B) antistatic agent containing lithium ions to 100 parts by mass of the whole antistatic agent is, for example, 50 parts by mass or more, and preferably 60 parts by mass or more. Preferably it is 75 mass parts or more.
Thus, by setting the proportion of the antistatic agent containing lithium ions, it is possible to effectively exhibit an appropriate antistatic ability as the sealant layer 2.
The upper limit of the ratio of “antistatic agent containing lithium ions” with respect to 100 parts by mass of the whole (B) antistatic agent is not particularly limited, and (B) the whole antistatic agent is “antistatic agent containing lithium ions”. It may be.

((C) polystyrene resin)
When the resin composition of this embodiment contains (C) polystyrene-type resin, adjustment of the balance of moderate antistatic ability and peeling strength can be aimed at.
The (C) polystyrene-based resin is not particularly limited. For example, polystyrene, styrene / butadiene / styrene block copolymer (SBS), styrene / ethylene / butadiene / styrene block copolymer (SEBS), styrene / isoprene / styrene. Block copolymer (SIS), styrene / ethylene / propylene / styrene block copolymer (SEPS), styrene- (meth) methyl acrylate copolymer, hydrogenated styrene block copolymer, impact polystyrene (HIPS; High Impact Polystyrene), general-purpose polystyrene resin (GPPS), and the like may be used in combination of two or more.
Among them, it is preferable to use a methyl styrene- (meth) acrylate copolymer from the viewpoint of high transparency and improving the antistatic ability and peel strength in a balanced manner.

((D) (meth) acrylic acid ester polymer)
When the resin composition of the present embodiment contains (D) (meth) acrylic acid ester polymer, as in the case of containing (C) polystyrene-based resin, the balance of appropriate antistatic ability and peel strength is achieved. Adjustments can be made.
Examples of the (D) (meth) acrylic acid ester polymer include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, isobutyl (meth) acrylate, Examples include polymers of (meth) acrylic acid esters selected from hexyl (meth) acrylate, ethylhexyl (meth) acrylate, and the like.
In addition, these polymers can be copolymers with other monomers as long as they do not correspond to the aforementioned components (A) and (C).
In the present embodiment, among these, it is preferable to use a methyl (meth) acrylate polymer from the viewpoint of easy availability and improving the antistatic ability and peel strength in a balanced manner.
In addition, this (D) (meth) acrylic acid ester polymer contains the structural unit derived from (meth) acrylic acid ester, for example, 60 mol% or more, Preferably it contains 70 mol% or more, More preferably, it contains 80 mol% or more.

In this embodiment, the total amount of the content of (C) polystyrene resin and (D) (meth) acrylic acid ester polymer with respect to 100 parts by mass of the resin composition constituting the sealant layer 2 is, for example, 3 parts by mass or more. The amount is preferably 5 parts by mass or more, and more preferably 7 parts by mass or more.
Thus, the suitable antistatic property as the sealant layer 2 can be achieved by setting the content of the (C) polystyrene resin and the (D) (meth) acrylic acid ester polymer.
In the present embodiment, the total content of (C) polystyrene resin and (D) (meth) acrylate polymer with respect to 100 parts by mass of the resin composition constituting sealant layer 2 is, for example, 30 parts by mass or less. It is preferably 25 parts by mass or less, more preferably 20 parts by mass or less.
Thus, a higher peel strength can be achieved by setting the contents of the (C) polyolefin resin and the (D) (meth) acrylic acid ester polymer.

  Moreover, in this embodiment, the resin composition which comprises the sealant layer 2 may contain the tackifying resin, the antiblocking agent, the slip agent, etc. which are shown below according to a use, for example.

  Examples of tackifying resins include petroleum resins (aliphatic petroleum resins, aromatic petroleum resins, alicyclic petroleum resins hydrogenated with the previous aromatic petroleum resin, etc.), rosin resins, terpene resins, styrene resins, coumarone And indene resin. These tackifier resins can be used alone or in combination of two or more. In the case where the adhesive layer is formed by extrusion lamination, alicyclic petroleum resin is particularly preferable from the viewpoint of stability against oxidation because it is melted and oxidized at a high temperature.

Examples of the antiblocking agent include silica, aluminosilicate (zeolite, etc.) and the like.
By containing the anti-blocking agent, blocking of the sealant layer 2 is relaxed.

Examples of slip agents include palmitic acid amide, stearic acid amide, behenic acid amide, oleic acid amide, erucic acid amide, oleyl palmamide, stearyl palmamide, methylene bis stearyl amide, methylene bis oleyl amide, ethylene bis oleyl amide, Examples include various amides such as ethylenebiserucic acid amide, polyalkylene glycols such as polyethylene glycol and polypropylene glycol, and hydrogenated castor oil.
When the sealant layer 2 contains a slip agent, processability such as extrusion processing, roll release property, film slipperiness, and the like are improved.

  In addition, the sealant layer 2 contains various additives such as various conductive materials, lubricants, plasticizers, antioxidants, ultraviolet absorbers, colorants, various surfactants, inorganic fillers and the like within a range not impairing the characteristics. You may go out. Moreover, the coating process may be given.

  In the present embodiment, the thickness of the sealant layer 2 is preferably 2 μm or more and 30 μm or less, and more preferably 5 μm or more and 20 μm or less. If the thickness of the sealant layer 2 is not more than the above upper limit value, it becomes easy to control the seepage during heat sealing, and if the thickness of the sealant layer 2 is not less than the above lower limit value, the cover is covered. The peel strength of the tape 10 with respect to the carrier tape 20 tends to be suitable.

In the present embodiment, the surface resistivity of the sealant layer 2 composed of the above resin composition is preferably 1.0 × 10 ¹¹ Ω / cm ² or less, and 7.0 × 10 ¹⁰ Ω / cm ² or less. It is more preferable that it is 5.0 × 10 ¹⁰ Ω / cm ² or less.
Such surface resistivity can be easily achieved by appropriately setting the type and amount of the antistatic agent described above.
Further, the lower limit value of the surface resistivity of the sealant layer 2 is not particularly limited, but is, for example, 1.0 × 10 ⁵ Ω / cm ² or more.
In addition, this surface resistivity can be measured using a surface resistance measuring device (manufactured by SIMCO) under an environment of a temperature of 23 ° C. and a humidity of 50% based on JIS K6911.

<Conductive layer 3>
In addition to the base material layer 1 and the sealant layer 2 described above, the electronic component packaging cover tape 10 according to the present embodiment may be provided with a conductive layer 3 as shown in FIG.
In FIG. 2, the example which provided this electroconductive layer 3 in the surface on the opposite side to the surface in which the sealant layer 2 was provided in the base material layer 1 is shown.
By laminating such a conductive layer 3, it is possible to more effectively suppress the accumulation of static electricity when a package body in which electronic components are packaged is obtained. In particular, in the actual process, the condition that the package 100 is transported after the bottom surface 20a (see FIG. 3) of the carrier tape and the surface 10a (see FIG. 3) of the cover tape are in close contact with each other is adopted. It is preferable to provide such a conductive layer 3 as 10.

  Examples of the material forming the conductive layer 3 include those containing an aziridinyl compound and a ring-opening compound thereof. Such an 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-aziridinecarboxamide) ), Triethylenemelamine, trimethylolpropane-tri-β (2-methylaziridine) propionate, bisisophthaloyl-1-methylaziridine, tri-1-aziridinylphosphine oxide, tris-1-2-methyl Examples include aziridine phosphine oxide. 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.

  Other than the above anilidyl compounds, the conductive layer 3 may contain an ester compound. Such an 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. Etc.

The material forming the conductive layer 3 preferably contains a conductive polymer from the viewpoint of reducing the surface resistance value of the conductive layer 3 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.
In addition, a surfactant type antistatic agent may be included in the conductive layer 3.

<Other layers>
The electronic component packaging cover tape 10 according to this embodiment may be provided with an intermediate layer (not shown) between the base material layer 1 and the sealant layer 2. By doing so, the cushioning property of the entire cover tape 10 can be improved.

  Examples of the material forming the intermediate layer include olefin resins, styrene resins, and cyclic olefin resins. Especially, it is preferable that an olefin resin is included from a viewpoint of improving the cushioning property of the whole cover tape.

  When the intermediate layer is provided, the thickness is preferably 10 μm or more and 30 μm or less, and more preferably 15 μm or more and 25 μm or less, from the viewpoint of improving the cushioning property of the entire cover tape.

  The cover tape 10 according to the present embodiment may be provided with an adhesive layer between the base material layer 1 and the sealant layer 2 or between the base material layer 1 and the conductive polymer layer 3. By doing so, the mechanical strength of the cover tape 10 can be improved.

  As a material for forming the above-mentioned adhesive layer, it is possible to use various known solvent-based or water-based anchor coating agents such as isocyanate, polyurethane, polyester, polyethyleneimine, polybutadiene, polyolefin, and alkyl titanate. it can.

  In addition, the adhesion between the base material layer 1 and the sealant layer 2 can be improved by performing corona treatment on the base material layer 1. This corona treatment may be performed by appropriately selecting known conditions.

[How to use cover tape 10 for packaging electronic parts]
Then, the example of the usage method of the cover tape 10 of this embodiment is demonstrated, referring FIG.
As shown in FIG. 3, the cover tape 10 is used as a cover material for a belt-like 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. Hereinafter, the structure obtained by bonding the cover tape 10 and the carrier tape 20 will be described as a packaging body 100 for electronic components.

In an actual electronic device manufacturing site, the electronic component package 100 is manufactured in the following procedure. First, an electronic component is accommodated in the pocket 21 of the carrier tape 20. Next, the cover tape 10 is bonded 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.
The structure containing such electronic components is transported 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.

  After this structure is transported to the work area, the cover tape 10 is peeled off from the carrier tape 20 and the accommodated electronic component is taken out. At this time, since the cover tape 10 of the present embodiment is configured by the specific sealant layer 2, it can suppress the generation of static electricity while exhibiting an appropriate peel strength.

  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.

<Preparation of resin composition>
In each Example and each comparative example, each component was mix | blended with the mixing | blending shown in Table 1, and the resin composition was obtained. In addition, about each component in Table 1, it is shown below.
-Polyolefin resin 1: Ethylene-ethyl acrylate copolymer (manufactured by NUC Corporation; trade name “NUC-6570”, ethyl acrylate ratio 25% by mass)
・ Polyolefin resin 2: ethylene-methyl acrylate copolymer (manufactured by Nippon Polyethylene Co., Ltd .; trade name “Lex Pearl EB440H”, methyl acrylate ratio 20 mass%)
Polyolefin-based resin 3: ethylene-methyl methacrylate copolymer (manufactured by Sumitomo Chemical Co., Ltd .; trade name “Aklift WK402”, methyl methacrylate ratio 25% by mass)
Polyolefin resin 4: Ethylene-vinyl acetate copolymer (Mitsui DuPont Polychemical Co., Ltd .; trade name “Evaflex EV260”, vinyl acetate ratio 28% by mass)
Antistatic agent 1: Antistatic agent containing lithium ions (manufactured by Sanyo Chemical Co., Ltd .; trade name “Peletron LMP”)
Antistatic agent 2: Antistatic agent substantially free of lithium ions (manufactured by Sanyo Chemical Co., Ltd .; trade name “Pelestat 212”)
Polystyrene resin 1: Styrene- (meth) methyl acrylate copolymer (manufactured by Nippon Steel Chemical Co., Ltd .; trade name “Estyrene MS-750”)
Polystyrene resin 2: General-purpose polystyrene resin (manufactured by Toyostyrene Co., Ltd .; trade name “Toyostyrene G100C”)
・ (Meth) acrylic acid ester polymer 1: methyl methacrylate homopolymer (manufactured by Sumitomo Chemical Co., Ltd .; trade name “SUMIPEX MGSV”)

<Manufacture of cover tape>
A low-density polyethylene (trade name Petrocene 203, manufactured by Tosoh Corporation) is used as an intermediate layer on a 12-μm thick biaxially stretched polyester film (trade name: E7415, manufactured by Toyobo Co., Ltd.) at an extrusion temperature of 300 ° C. A film was formed to a thickness of 20 μm.
On the intermediate layer thus formed, a resin composition having the composition shown in Table 1 as a sealant layer was formed to a thickness of 10 μm at an extrusion temperature of 280 ° C. to obtain a cover tape.

  The following evaluation was performed using the cover tape obtained by the above method.

<Evaluation method>
(Surface resistivity)
The surface resistivity of the sealant surface of each cover tape obtained in Examples and Comparative Examples was measured using a surface resistance measuring device (manufactured by SIMCO) under a temperature of 23 ° C. and a humidity of 50% based on JIS K6911. .

(Peel strength)
Each cover tape obtained in Examples and Comparative Examples was slit to a width of 5.3 mm, and on the surface of a paper carrier tape (manufactured by Tokyo Paper Industries), a taping machine (manufactured by Tokyo Wells: TWA-6621) was used. Heat sealing was carried out under the conditions of 1 ° C., 1 kg / cm ² and 0.1 second, and the peel strength immediately after the heat sealing was measured. The peel strength was measured using a peel tester under the condition of a peel speed of 300 mm / min and a peel angle of about 180 °.

  The evaluation results regarding the evaluation items are shown in Table 1 below.

  As shown in Table 1, in the cover tape of each example, good peel strength can be achieved while keeping the surface resistivity low.

DESCRIPTION OF SYMBOLS 1 Base material layer 2 Sealant layer 3 Conductive layer 10 Cover tape for electronic component packaging (cover tape)
10a Cover tape surface 20 Carrier tape 20a Carrier tape bottom surface 21 Pocket 100 Packaging

Claims (7)

A resin composition constituting a sealant layer of a cover tape for sealing a carrier tape having a recess capable of accommodating an electronic component,
The resin composition is
(A) a polyolefin-based resin;
(B) an antistatic agent;
(C) polystyrene resin and / or (D) (meth) acrylic acid ester polymer;
Including
The antistatic agent (B) includes an antistatic agent containing lithium ions,
The resin composition whose content of the said (A) polyolefin resin with respect to 100 mass parts of the said resin compositions is 20 mass parts or more. The resin composition according to claim 1,
The resin composition whose content of the said (B) antistatic agent with respect to 100 mass parts of said resin compositions is 25 mass parts or less. The resin composition according to claim 1 or 2,
A resin composition comprising a styrene- (meth) methyl acrylate copolymer as the (C) polystyrene resin. The resin composition according to any one of claims 1 to 3,
The resin composition containing a (meth) acrylic acid methyl polymer as said (D) (meth) acrylic acid ester polymer. The resin composition according to any one of claims 1 to 4, wherein
A resin composition having a surface resistivity of 1.0 × 10 ¹¹ Ω / cm ² or less when a sealant layer is produced from the resin composition. A resin composition according to any one of claims 1 to 5,
The (A) polyolefin resin is a kind selected from the group consisting of an ethylene-vinyl acetate copolymer, an ethylene-aliphatic unsaturated carboxylic acid copolymer, an ethylene-aliphatic unsaturated carboxylic acid ester copolymer, and an ionomer. A resin composition comprising the above resin. A cover tape for sealing a carrier tape having a recess capable of accommodating an electronic component,
A cover tape provided with the sealant layer comprised with the resin composition as described in any one of Claims 1 thru | or 6.

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