JP2011063662A - Sealant material, cover tape, and packaging body for transporting electronic component - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a sealant material in which a zipping phenomenon and stickiness, occurring in exfoliation, are inhibited from occurring. <P>SOLUTION: The sealant material used in a carrier tape for transporting an electronic component soaked with styrenic resin contains at least (A) an ethylene-vinyl acetate copolymer which has a vinyl ester copolymerization ratio of 3-20 mass% and a structural unit derived from ethylene and a structural unit derived from vinyl acetate, (B) an ethylene-α-olefin copolymerization elastomer, and (C) a tackifier, in which proportions of the (A), (B), and (C) are 41-80 pts.mass, 19-50 pts.mass, and 1-9 pts.mass, respectively, based on 100 pts.mass of the (A) to (C) in total amount. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a sealant material that is in close contact with a carrier tape using a styrenic resin suitable for storing and transporting IC chips and the like, and a cover tape using the same and a package for transporting electronic components.

  Carrier tapes used for transporting and storing microchips such as semiconductors and electronic components are widely known. This carrier tape can be stored and transported by embedding one microchip or the like, which is difficult to handle because it is too small, one by one in a recess provided in the carrier tape. A cover tape for closing a recess in which a microchip or the like is embedded is adhered to the carrier tape by heat sealing or the like, and packaged. After transporting in this state, the carrier tape is set in a component assembly machine (mounting machine) called a mounter, and the embedded microchip or the like can be taken out.

  In addition to microchips and the like, conventionally, plastic containers having easily openable lid materials are known as containers for foods and drinks such as cup noodles, jelly and yogurt, and pharmaceuticals. As a heat seal material provided on such an easy-open lid, for example, a composition of an ethylene / vinyl acetate copolymer and a tackifying resin, polyethylene or a low crystalline ethylene / α-olefin copolymer, etc. A heat seal material blended with is known.

  However, plastic materials used for the carrier tape main body are also diversified, and the heat sealability desired by the conventional heat seal material may not be maintained. Further, depending on the application, the required heat sealability differs, and other characteristics are required.

  As a technique related to the above, an ethylene copolymer composition containing an ethylene / unsaturated ester copolymer, an elastomer, a crystalline polyolefin, and a tackifier in a desired range is disclosed (for example, Patent Document 1). See), and it is said that it is excellent in sealing property, low-temperature heat-sealing property, and easy-opening property to food and beverage containers such as polypropylene and polystyrene.

  Also disclosed is a heat-sealable resin composition obtained by melt-mixing an ethylene / vinyl ester having a predetermined vinyl ester content, a copolymer of ethylene and propylene or butene-1, and a tackifier (for example, And Patent Documents 2 to 3). This is known as an easy-open heat-seal material used for food packaging such as pudding and jelly.

WO2006 / 090722 JP 58-47038 A Japanese Patent Publication No. 63-29894

  However, as a sealant material for carrier tape that encloses a very small IC chip of about 0.5 mm, it has easy peelability to the carrier tape, and zipping between the sealant material and the IC chip when opened When the sealant material (cover tape) is peeled from the carrier tape, a phenomenon that generates fine vibrations may occur. Such vibration causes the IC chip to jump and shift its position, or causes the IC chip to jump out of the carrier tape and spill out, resulting in a problem that the mounting rate is lowered.

  It is desirable that no stickiness occurs even after long-term storage. If stickiness occurs, blocking may occur between the cover tape and the carrier tape during the mounting process, which may cause a trouble associated with changes in peel strength or peel feeling (zipping).

  The present invention has been made in view of the above, and it is an object of the present invention to provide a sealant material in which the occurrence of zipping phenomenon and stickiness occurring at the time of peeling is suppressed, a cover tape using the sealant material, and a package for transporting electronic components. An object is to achieve the object.

Specific means for achieving the above object are as follows.
<1> Used for carrier tapes for transporting electronic components containing a styrene-based resin, (A) the copolymerization ratio of vinyl ester is 3 to 20% by mass, and a structural unit derived from ethylene and a structure derived from vinyl acetate An ethylene / vinyl acetate copolymer having a unit, (B) an ethylene / α-olefin copolymer elastomer, and (C) a tackifier, and the ratio of (A), (B) and (C) However, it is a sealant material which is 41-80 mass parts, 19-50 mass parts, and 1-9 mass parts, respectively with respect to 100 mass parts of total amounts of said (A)-(C).

<2> The sealant material according to <1>, wherein the ethylene / α-olefin copolymer elastomer is an ethylene / butene copolymer having a density of 860 to 900 kg / m ³ .

  <3> Further, the content ratio of (A) to (C) with respect to 100 parts by mass of the total amount includes 0.1 to 10 parts by mass of (D) the antiblocking agent <1> or the above It is a sealant material as described in <2>.

  <4> Further, the content ratio of (A) to (C) to 100 parts by mass of the total amount includes 0.1 to 5 parts by mass of (E) slip agent, <1> to < 3>. The sealant material according to any one of 3>.

  <5> Further, any one of <1> to <4>, further including at least one ethylene / vinyl acetate copolymer having a different copolymerization ratio between the ethylene / vinyl acetate copolymer (A) and the vinyl ester The sealant material according to one.

  <6> A carrier tape for transporting an electronic component, which has a layer containing the sealant material according to any one of <1> to <5> above on a base material, and includes a styrene resin. It is a cover tape that is used by heat-bonding.

  <7> A carrier tape for transporting electronic components produced by including a styrene-based resin, and a layer containing the sealant material according to any one of <1> to <5> above on a substrate. And a cover tape thermally bonded to the electronic component carrying carrier tape.

ADVANTAGE OF THE INVENTION According to this invention, the sealant material by which generation | occurrence | production of the zipping phenomenon and stickiness which arise at the time of peeling was suppressed can be provided. Also,
ADVANTAGE OF THE INVENTION According to this invention, the cover tape and the electronic component conveyance package which suppressed generation | occurrence | production of the zipping phenomenon at the time of peeling and stickiness can be provided.

  Hereinafter, the sealant material, the cover tape, and the electronic component carrying package of the present invention will be described in detail.

The sealant material of the present invention is a sealant material used for a carrier tape for transporting electronic components containing a styrene-based resin, and has a copolymerization ratio of at least (A) vinyl ester of 3 to 20% by mass. An ethylene / vinyl acetate copolymer having a structural unit derived from vinyl acetate and a structural unit derived from vinyl acetate, and (B) an ethylene / α-olefin copolymer elastomer,
(C) a tackifier, and the content ratio of the components (A), (B) and (C) is 41 to 80 parts per 100 parts by mass of the total amount of the components (A) to (C), respectively. It is comprised so that it may become a mass part, 19-50 mass parts, and 1-9 mass parts.

  In the present invention, the ethylene / vinyl acetate copolymer contains a predetermined range of vinyl ester, and the ratio between the ethylene / α-olefin copolymer elastomer and the tackifier is within the predetermined range, so that zipping that occurs at the time of opening While suppressing the occurrence of the phenomenon, the occurrence of stickiness can also be suppressed.

(A) Ethylene / vinyl acetate copolymer The sealant material of the present invention is an ethylene / acetic acid copolymer having a vinyl ester copolymerization ratio of 3 to 20% by mass and having a structural unit derived from ethylene and a structural unit derived from vinyl acetate. It contains at least one vinyl copolymer (hereinafter also referred to as “ethylene / vinyl acetate copolymer in the present invention”). By including this copolymer, good heat sealability is imparted.

In the present invention, the content ratio of the ethylene / vinyl acetate copolymer in the sealant material is 41 to 41 parts by mass relative to 100 parts by mass of the following components (B) to (C) and the ethylene / vinyl acetate copolymer. The range is 80 parts by mass. When the content of the ethylene / vinyl acetate copolymer is less than 41 parts by mass, the workability deteriorates, and when it exceeds 80% by mass, the balance between the heat seal strength and the feeling of peeling (preventing zipping) is deteriorated.
Among these, the content of the ethylene / vinyl acetate copolymer is that of the components (B) to (C) and the ethylene / vinyl acetate copolymer from the viewpoint of suppressing the occurrence of stickiness while imparting processability and heat sealability. The range of 50-70 mass parts is preferable with respect to 100 mass parts of total amount, Furthermore, the range of 50-65 mass parts, Especially preferably, the range of 55-60 mass parts is preferable.

  The ethylene / vinyl acetate copolymer in the present invention is a copolymer obtained by copolymerizing at least ethylene and vinyl acetate, and in some cases, other monomers may be further copolymerized. The copolymerization ratio of the vinyl ester in the ethylene / vinyl acetate copolymer is 3 to 20% by mass with respect to the total mass of the ethylene / vinyl acetate copolymer. Examples of the vinyl ester include vinyl acetate and vinyl propionate, and the copolymer unit of the copolymer may include a plurality of types of vinyl ester-derived structural units. In the present invention, at least a vinyl acetate-derived structural unit is included. The case where it contains as a copolymerization unit is preferable. When the copolymerization ratio of the vinyl ester is less than 3% by mass, the heat seal strength is insufficient, and when it exceeds 20% by mass, the stickiness increases. Among them, the copolymerization ratio of the vinyl ester is preferably 3 to 10% by mass with respect to the total mass of the ethylene / vinyl acetate copolymer for the same reason.

  The ethylene / vinyl acetate copolymer in the present invention is a binary copolymer of ethylene and vinyl acetate in a proportion of 3 to 20% by mass (preferably 3 to 10% by mass) with respect to the total mass of the copolymer. preferable.

(B) Ethylene / α-olefin copolymer elastomer The sealant material of the present invention contains at least one ethylene / α-olefin copolymer elastomer. By including this elastomer, the occurrence of zipping at the time of peeling after heat sealing to a carrier tape containing a styrene resin is suppressed.

In the present invention, the content ratio of the ethylene / α-olefin copolymer elastomer in the sealant material is set to 100 parts by mass of the total amount of the component (A) and the following component (C) and the ethylene / α-olefin copolymer elastomer. On the other hand, it is set as the range of 19-50 mass parts. When the content of the ethylene / α-olefin copolymer elastomer is less than 19 parts by mass, the effect of suppressing the occurrence of zipping is small, and when it exceeds 50% by mass, the stickiness increases and the workability deteriorates.
Among them, the content of the ethylene / vinyl acetate copolymer is the component (A) and the component (C) and the ethylene / α-olefin copolymer elastomer from the viewpoint of suppressing the occurrence of zipping and the occurrence of stickiness. The range of 25-45 mass parts is preferable with respect to the total amount of 100 mass parts, more preferably 30-45 mass parts, and particularly preferably 30-40 mass parts.

  As an alpha olefin, a C2-C12 thing is preferable, for example, ethylene, propylene, 1-butene, 1-hexene, 1-octene, 4-methyl-pentene etc. are mentioned.

  Examples of the ethylene / α-olefin copolymer elastomer include an ethylene / propylene copolymer, an ethylene / 1-butene copolymer, an ethylene / 1-hexene copolymer, and an ethylene / 1-octene copolymer. .

The density of the ethylene / α-olefin copolymer elastomer is preferably in the range of 860 to 900 kg / m ³ and more preferably in the range of 880 to 890 kg / m ³ from the viewpoint of heat sealability and suppression of occurrence of zipping.

(C) Tackifier The sealant material of the present invention contains at least one tackifier. By containing a tackifier, the heat seal strength is increased and the workability required during molding is provided.

In this invention, the tackifier in a sealant material is contained in the range of 1-9 mass parts with respect to 100 mass parts of total amounts of said component (A)-(B) and tackifier. When the content of the tackifier is 1 part by mass or more, it means that the content is substantially included for imparting heat seal strength and workability. When the content is less than 1 part by mass, the heat seal strength may be insufficient. The workability when film-forming is deteriorated. When the content of the tackifier exceeds 9% by mass, the strength tends to be excessive and zipping occurs.
Among them, from the viewpoint of suppressing the occurrence of zipping after giving workability, a range of 2 to 8 parts by mass is preferable with respect to 100 parts by mass of the total amount of the components (A) to (B) and the tackifier, Furthermore, the range of 3-7 mass parts is preferable.

  As the tackifier, a tackifying resin can be used. Examples of tackifiers include aliphatic hydrocarbon resins, alicyclic hydrocarbon resins, aromatic hydrocarbon resins, polyterpene resins, rosins, styrene resins, coumarone / indene resins, and the like. it can.

  As the aliphatic hydrocarbon resin, for example, a fraction containing at least one mono- or diolefin having 4 to 5 carbon atoms such as 1-butene, isobutene, butadiene, 1,3-pentadiene, isoprene, and the like is polymerized. And the resulting resin.

  Examples of the alicyclic hydrocarbon resin include a resin obtained by polymerizing a cyclic monomer such as cyclopentadiene, a resin obtained by polymerizing a diene component in the spent C4 to C5 fraction after cyclization and dimerization, and aromatic Examples include resins obtained by intranuclear hydrogenation of an aromatic hydrocarbon resin.

  Examples of the aromatic hydrocarbon resin include a resin obtained by polymerizing a fraction containing at least one vinyl aromatic hydrocarbon having 8 to 10 carbon atoms such as vinyltoluene, indene, and α-methylstyrene, or Examples thereof include resins obtained by copolymerizing these fractions and the aliphatic hydrocarbon fraction.

  Examples of the polyterpene resins include α-pinene polymers, β-pinene polymers, dipentene polymers, terpene / phenol copolymers, α-pinene / phenol copolymers, and hydrogenated products thereof. Can do.

  Examples of the rosins include, for example, rosins such as gum rosin, wood rosin and tall oil, and modified products thereof. Examples of the modified products include those subjected to modification such as hydrogenation, disproportionation, dimerization, and esterification. it can.

  Examples of the styrene resin include low molecular weight resinous polymers obtained by polymerizing styrene monomers such as styrene, vinyl toluene, α-methyl styrene, and isopropyl toluene.

  The tackifier tends to be preferably a resin having a softening point of 85 to 130 ° C. When the softening point is generally 85 ° C. or higher, the effect of excellent heat resistance tends to be exhibited, and when it is 130 ° C. or lower, the effect of excellent adhesiveness tends to be exhibited.

(D) Antiblocking agent The sealant material of the present invention preferably contains an antiblocking agent. By containing an antiblocking agent, the blocking of the film is alleviated.

  Examples of the antiblocking agent include silica, aluminosilicate (zeolite, etc.) and the like.

In this invention, the antiblocking agent in a sealant material can be contained in 0.1-10 mass parts with respect to 100 mass parts of total amounts of said component (A)-(C). The content of the anti-blocking agent being 0.1 parts by mass or more indicates that it is substantially included for imparting blocking properties. When the content is 0.1 parts by mass or more, the stickiness is suppressed and the occurrence of blocking is prevented. High effect. When the content of the antiblocking agent is 10% by mass or less, it is advantageous in that the transparency can be kept high.
Especially, from a sticky prevention and a transparent viewpoint, the range of 1-3 mass parts is preferable with respect to 100 mass parts of total amounts of the said component (A)-(C).

(E) Slip agent The sealant material of the present invention preferably contains a slip agent. By containing a slip agent, processability such as extrusion, roll-off property, film slipperiness and the like are improved.

  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.

In this invention, the slip agent in a sealant material can be contained in the range of 0.1-5 mass parts with respect to 100 mass parts of total amounts of said component (A)-(C). The slip agent content of 0.1 part by mass or more indicates that the slip agent is substantially included for imparting blocking properties. When the slip agent content is 0.1 part by mass or more, processability such as extrusion, roll-off property , Film slipperiness and the like are improved. If the content of the slip agent is 5% by mass or less, on the contrary, it is advantageous in that excessive slip does not occur and in that the sealant material is not contaminated.
Especially, the range of 0.2-1 mass part is preferable with respect to 100 mass parts of total amounts of the said component (A)-(C) from a viewpoint of workability, a roll-off property, and film slipperiness.

  In addition to the above components, the sealant material of the present invention can be exemplified by additives such as antioxidants, heat stabilizers, light stabilizers, pigments, and dyes as necessary.

  The sealant material of the present invention is prepared by mixing the components (A) to (C) and the components (D) to (E) and other additives blended as necessary, either simultaneously or sequentially. can do. In preparing the sealant material of the present invention, a single screw extruder, a twin screw extruder, a Banbury mixer, various kneaders, and the like can be used.

  The sealant material of the present invention has a melt flow rate (MFR; the same shall apply hereinafter) at 190 ° C. and 2160 g load in accordance with JIS K7210-1999 in consideration of processability such as extrusion and heat seal strength, and 1 to 100 g / 10. Minutes are preferred, especially those from 3 to 50 g / 10 minutes.

  The sealant material of the present invention is used for carrier tapes for transporting electronic components containing styrene resin (especially carrier tapes made of styrene resin), and is laminated on the carrier tape and bonded by heat sealing or the like. For example, the storage unit storing the IC chip can be closed and stored and transported.

  The sealant material of the present invention can be used by a method in which a film is formed in advance by a casting method or an inflation method, and is bonded to a carrier tape containing a styrene resin by a dry lamination method.

  Next, the cover tape of the present invention and the electronic component transport packaging body using the same will be described in detail.

  The cover tape of the present invention is used by heat-sealing a carrier tape for conveying an electronic component produced by including a styrene resin, and a base material and the sealant material of the present invention on the base material (Hereinafter also referred to as “sealant layer”). Since the cover tape of the present invention is composed of the sealant material of the present invention, it improves the heat sealability with a carrier tape using a styrene resin, and the effect of preventing the occurrence of zipping when peeling after heat sealing. Can be made.

In addition, the carrier tape for transporting electronic components to which the cover tape of the present invention can be applied is not only the one prepared by including the styrene resin described above, but also the one made of polycarbonate or paper. Applicable.

  The thickness of the sealant layer is preferably 3 to 50 μm. When the thickness is within the above range, good heat sealability can be obtained.

  There is no restriction | limiting in particular as a base material, Paper, aluminum, polyester (for example, polyethylene terephthalate), polyethylene, polypropylene, polystyrene, aluminum vapor deposition polyester, aluminum vapor deposition polypropylene, silica vapor deposition polyester, etc. are mentioned. These base materials may have not only a single layer structure but also a laminated structure of two or more layers.

  The package for transporting electronic components of the present invention has a carrier tape for transporting electronic components manufactured by including a styrene-based resin, and a layer containing the above-described sealant material of the present invention on a substrate. And a cover tape that is thermally bonded to the component transport carrier tape. Since the package for transporting electronic components of the present invention is configured using the sealant material of the present invention, heat sealability with a carrier tape using a styrenic resin, and occurrence of zipping when peeling after heat seal Excellent prevention effect. In addition to this, suitable heat sealability and peeling feeling (prevention of zipping) are also shown for a carrier tape using polycarbonate or a carrier tape using paper.

  Carrier tape for transporting electronic components is set in a component assembly machine (mounting machine), embedded in electronic components such as microchips, stored, transported, etc., and then can be taken out as desired It is formed. In the present invention, a carrier tape made of styrene resin is particularly preferable as the carrier tape for transporting electronic components containing styrene resin.

  The package for transporting electronic components uses a carrier tape and cover tape for transporting electronic components, on an opening surface where an accommodation portion in which an electronic component (e.g., IC chip) of the carrier tape for transporting electronic components is accommodated is opened. The cover tape is overlaid so that the sealant layer faces the opening surface, and is heat-sealed from above the cover tape.

  EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited to the following examples unless it exceeds the gist thereof. Unless otherwise specified, “part” is based on mass.

(Example 1, Comparative Examples 1-4)
-Preparation of sealant composition-
Each component was put into a single screw extruder (manufactured by Nakatani Machinery Co., Ltd.) so as to have the composition shown in Table 1 below, and melt-kneaded at 140 ° C. to prepare a sealant composition.

-Preparation and evaluation of evaluation film-
Next, stretched polyethylene terephthalate (PET) having a thickness of 12 μm and low-density polyethylene (LDPE) having a thickness of 20 μm were overlapped and extruded to prepare a stretched PET / LDPE laminated film having a multilayer structure. On the LDPE surface of this stretched PET / LDPE laminated film, the sealant composition prepared above was extruded by extrusion lamination at a thickness of 30 μm using a 40 mmφT die molding machine (manufactured by Nakatani Machinery Co., Ltd.). An evaluation film having a laminated structure of LDPE / stretched PET was produced. The extrusion lamination was performed under the conditions of a resin temperature of 190 ° C. and a processing speed of 30 m / min. About the film workability at this time, the presence or absence of generation | occurrence | production of a film crack etc. was observed and the propriety of processing was evaluated. The evaluation results are shown in Table 2 below.

-Production of laminated samples-
Separately from the above, a polystyrene sheet (Clearen CST-2401, manufactured by Denki Kagaku Kogyo Co., Ltd.) was prepared as an adherend. On this polystyrene sheet, the evaluation film produced above was overlaid so that the sealant layer faced the polystyrene sheet, and heat-sealed using a heat sealer under the following conditions to obtain a laminated sample.
<Condition>
-Heat sealer: Tester Sangyo Co., Ltd.-Heat seal temperature: 100-150 ° C
・ Heat seal pressure: 0.2MPa
・ Heat seal time: 0.5 seconds ・ Heat seal bar: 1mm width x 300mm length x 2

-Evaluation-
The produced laminated sample was aged under the following conditions (a) and (b), and the sample after the aging treatment was measured and evaluated as follows. The results of measurement and evaluation are shown in Table 2 below.
<Aging conditions>
(A) Leave in a room at 23 ° C. and 50% RH for 1 day. (B) Leave in a thermostatic chamber at 60 ° C. and 90% RH for 5 days.

[Heat seal strength]
For each sample after aging treatment under both conditions (a) and (b), using a peel strength tester VG-35 (manufactured by Vangguard), from a polystyrene sheet as an adherend under the following peeling conditions The evaluation film was peeled off, and the strength at the time of peeling was measured.
<Peeling conditions>
・ Peeling speed: 300 mm / min
・ Peeling angle: 165 ° C. to 180 ° C. (angle between the evaluation film and the pulling direction when peeling)
・ Peeling direction: peeling in the longitudinal direction

[Zipping]
Using each sample after the aging treatment under the condition (b), the evaluation film was manually peeled from the polystyrene sheet as the adherend, and the presence or absence of a tingling sound generated at the time of peeling was evaluated.

[Sticky]
For each sample after aging treatment under the condition (b), the evaluation film was peeled off from the polystyrene sheet as the adherend, and the presence or absence of stickiness was felt when the sealant layers of the evaluation film after peeling were brought into contact with each other. evaluated.

As shown in Table 2, in the examples, film processing was possible and generation of zipping and stickiness was suppressed. In addition, the heat seal strength showed a good performance not to be excessive in strength.
On the other hand, in Comparative Example 1, since the amount of the tackifier was large, zipping and stickiness were generated, and the seal strength was excessive. On the contrary, in Comparative Example 2 in which no tackifier was added, film cracking occurred and the film processability was poor. In Comparative Example 3 in which the ethylene / α-olefin copolymer elastomer was not added, zipping deteriorated.

Claims (7)

Used in carrier tapes for transporting electronic components that contain styrenic resin,
(A) an ethylene / vinyl acetate copolymer having a copolymerization ratio of 3 to 20% by mass of a vinyl ester and having a structural unit derived from ethylene and a structural unit derived from vinyl acetate;
(B) an ethylene / α-olefin copolymer elastomer;
(C) a tackifier,
The ratio of (A), (B) and (C) is 41 to 80 parts by mass and 19 to 50 parts by mass with respect to 100 parts by mass of the total amount of (A) to (C), respectively. And 1-9 parts by mass of a sealant material. The sealant material according to claim 1, wherein the ethylene / α-olefin copolymer elastomer is an ethylene / butene copolymer having a density of 860 to 900 kg / m ³ .   Furthermore, the content ratio with respect to 100 mass parts of total amounts of said (A)-(C) contains 0.1-10 mass parts (D) antiblocking agent, The Claim 1 or Claim 2 characterized by the above-mentioned. Sealant material.   Furthermore, the content ratio with respect to 100 mass parts of the total amount of said (A)-(C) contains 0.1-5 mass parts (E) slip agent, The any one of Claims 1-3 characterized by the above-mentioned. The sealant material according to item 1.   Furthermore, the ethylene-vinyl acetate copolymer (A) and at least 1 type of ethylene-vinyl acetate copolymer from which the copolymerization ratio of vinyl ester differs are described in any one of Claims 1-4. Sealant material.   It has a layer containing the sealant material according to any one of claims 1 to 5 on a base material, and is thermally bonded to a carrier tape for transporting an electronic component that is produced by including a styrene resin. Cover tape used.   A carrier tape for conveying an electronic component produced by including a styrene-based resin, and a layer containing the sealant material according to any one of claims 1 to 5 on a base material, the electronic component conveying And a cover tape thermally bonded to the carrier tape.