JPH1095448A - Lid material for carrier tape - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain excellent antistatic property, heat seal property, blocking resistance, and stable zip-up property by layering, on a base sheet, an intermediate layer formed of two kinds of copolymers whose composition is specified and a sealant layer which contains a conductive fine powder and a large- diameter inorganic filler. SOLUTION: On a base sheet 1 consisting of a biaxially oriented film, an intermediate layer 3 in which 50-250 pts.wt. of styrene-butadiene copolymer containing 100 pts.wt. of styrene and 100-100 pts.wt. of butadiene is compounded with 100 pts.wt. of ethylene α-olefin copolymer having a density of 0.900-0.940g/cm<3> is layered through an adhesive layer 2. Further, the intermediate layer' 3 is coated with a heat sealant layer 4 which contains 10-350 pts.wt. of conductive fine powder 7 of tin oxide and zinc oxide and 2-30 pts.wt. of inorganic filler 6 having a particle diameter of 0.4-3 times the average coat thickness of the heat sealant layer 4 based on 100 pts.wt. of heat sealing resin composition 8 so as to form a lid material 5.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a synthetic resin container for housing various industrial parts, for example, a carrier tape for housing a semiconductor element in a pocket portion of a concave portion formed in a carrier tape, covering the housing portion and heat sealing. Regarding the lid member, it belongs to a lid member on which an electronic component is mounted and which can be easily opened and peeled and has a stable peeling strength.

[0002]

The material of a synthetic resin container for accommodating various industrial parts, such as a carrier tape, is usually made of polyvinyl chloride, polystyrene, acrylonitrile, or the like.
Sheets such as butadiene / styrene copolymer (ABS), polyester (A-PET), and polycarbonate are easily formed. Further, the lid member is formed of a laminate in which a heat sealant layer mainly composed of a heat sealable resin composition (hereinafter, referred to as an HS resin composition) is provided on one surface of the film. The lid material is required to have stable heat sealability and peeling performance. A lid material having good low-temperature heat sealability is required to be stored at a temperature such as temperature, humidity, pressure (hardness of winding) when stored in a rolled state. Due to this, a blocking phenomenon may occur in which the heat sealant layer and the back surface adhere to each other. Further, as shown in FIG. 2, a carrier tape in which components are mounted in pockets 10 and a cover member 5 provided with a heat seal portion 11 with a specific width and width are stored in a roll for a long time. Depending on the humidity and humidity, the non-heat-sealed portion 12 of the flange of the carrier tape molded product may be blocked (adhered), which may cause a change in peel strength. In addition, the carrier tape or the lid member does not cause deterioration and destruction of the semiconductor element due to contact with the stored semiconductor element or static electricity generated when the lid member is peeled off, and also allows the contents to be visually observed. It is required to have a degree of transparency. In the electronic component mounting process, it is required that the lid material can be easily and stably peeled off. In addition, when the difference between the maximum value and the minimum value of the peel strength (hereinafter, referred to as zip-up in the present specification) with the progress of the peeling is large, the electronic component pops out or cannot be mounted at a predetermined position. There is.

The present invention has been made to solve the above-mentioned problems, particularly, to maintain excellent heat sealing properties and to solve blocking resistance, and to provide excellent antistatic properties and heat sealing properties to a carrier tape. It is an object of the present invention to provide a carrier tape lid having blocking resistance and stable zip-up properties.

[0004]

In order to solve the above-mentioned problems, a lid material of the present invention comprises a base sheet, an intermediate layer optionally laminated via an adhesive layer, and a heat sealant layer. In a cover material that can be heat-sealed to a carrier tape, the base sheet is a biaxially stretched film, and the composition of the intermediate layer is an ethylene / α-olefin copolymer having a density of 0.900 to 0.940 g / cm ³ (hereinafter, referred to as “the copolymer”). This is referred to as an EO copolymer.) 100 parts by weight of "styrene 1
A styrene-butadiene copolymer (hereinafter, referred to as an SB copolymer) consisting of 00 parts by weight and 10 to 100 parts by weight of butadiene ”” is 50 to 250 parts by weight. . Further, the heat sealant layer is based on 100 parts by weight of the HS resin composition.
A cover material for a carrier tape containing 10 to 350 parts by weight of conductive fine powder of tin oxide, zinc oxide, indium oxide, and titanium oxide, and 2 to 30 parts by weight of an inorganic filler. The carrier filler has a particle diameter of the inorganic filler of 0.4 to 3 times the average coating thickness of the heat sealant layer. Further, the surface resistivity of the heat sealant layer is 10 ^{5 to} 10 ¹² Ω / □,
The carrier tape cover material has a charge decay time not exceeding 2 seconds.

[0005]

2. Description of the Related Art Conventionally, heat sealing between a carrier tape and a cover material thereof has been required to have a predetermined strength so that the cover material does not peel off during transportation or storage and the electronic component does not fall off. However, if the peeling strength is too strong, there is a problem that the carrier tape vibrates and the electronic component jumps out of the pocket of the carrier tape when the cover material is peeled off in the mounting process of the electronic component. Therefore, the lid material is required to be heat-sealed with sufficient strength to the carrier tape and to have good releasability when mounting electronic components. There was a problem that it was extremely difficult to adjust the peel strength under conditions such as heat sealing temperature, time, and pressure. Further, the heat sealant layer having low-temperature heat sealability not only blocks in a wound state during storage, but also after heat-sealing the carrier tape and the lid member as described above, the non-woven fabric shown in FIG. There is also a problem that the heat seal portion 12 is adhered and adversely affects the peel strength. Also, even when an appropriate peel strength (10 to 120 g / mm) is obtained, if the zip-up of the peel strength is large, the mounting position of the electronic component may not be stable, and in some cases, the electronic component may jump out of the pocket. Also turned out.

[0006] As means for preventing the generation of static electricity in the cover material of the carrier tape, kneading conductive carbon black fine particles and metal fine particles into the carrier tape or applying a coating liquid containing these are performed. . Also,
As a means of preventing static electricity generation in the lid material, an antistatic agent such as a surfactant, conductive carbon black fine particles, and metal fine particles are kneaded into a heat sealant layer which is in direct contact with an electronic component, or a coating liquid containing these. It has been done to coat.

[0007] However, the conductive carbon black fine particles and metal fine particles which are antistatic agents contained in the above-mentioned carrier tape and lid material reduce the transparency of the sheet,
There is a problem that it is difficult to externally check the stored electronic components. Further, when a surfactant is applied, there is a problem in that the surfactant is deposited on the surface of the heat sealant layer of the lid material, the heat sealing property becomes unstable, and the heat sealing becomes defective.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS As shown in FIG. 1, a cover material of the present invention is a carrier tape comprising a base sheet 1, an intermediate layer 3 and a heat sealant layer 4 via an adhesive layer 2 provided as required. In the lid member 5, the base sheet is a biaxially stretched film, and the composition of the intermediate layer is 100 parts by weight of the EO copolymer having a density of 0.900 to 0.940 g / cm ³ , The SB copolymer comprising 100 parts by weight of styrene and 10 to 100 parts by weight of butadiene "is composed of 50 to 250 parts by weight. The heat sealant layer 4 is composed mainly of tin oxide-based, zinc oxide-based, indium oxide-based and / or titanium oxide-based conductive fine powder 7 based on 100 parts by weight of the HS resin composition 8. ~ 350
Parts by weight and 2 to 30 parts by weight of the inorganic and inorganic filler 6. And, the particle diameter of the inorganic filler is 0.4 mm of the average coating thickness of the heat sealant layer.
In addition, the surface resistivity of the heat sealant layer 4 is 10 times or more.
^The carrier tape lid 5 has a charge decay time of ^{5 to} 10 ¹² Ω / □ and does not exceed 2 seconds.

The "average coating thickness" described in this specification is a thickness assuming that the heat sealant layer has formed a uniform film, and is calculated as follows. The density D of the solid content of the heat sealant layer coating liquid obtained by drying and solidifying the solvent is measured by an ordinary method. Then, the coating amount G (solid content g / m ² ) of the heat sealant layer is measured, and the average thickness T (μm) is calculated from the equation (1).

[0010]

## EQU1 ## T = G / D

The stretched film used for the substrate sheet of the present invention is formed by uniaxially or biaxially stretching a thermoplastic resin such as polyester such as polyethylene terephthalate and polyethylene naphthalate, polyolefin such as polypropylene, polyamide such as nylon and polycarbonate. And a film having a thickness of 3 to 25 μm. And, in order to strengthen and stabilize the strength with the intermediate layer, the surface on which the intermediate layer is to be provided may be subjected to a corona discharge treatment, a plasma treatment, a sand blast treatment, or a surface treatment such as providing a primer layer, if necessary, in advance. it can. Further, an antistatic treatment can be performed by incorporating a surfactant or the like.

The base sheet is formed by using at least the above-mentioned stretched film in a single layer, or by compounding a two-layered film with the same or different type of stretched film or unstretched film via an adhesive layer. You can also.
The adhesive layer is mainly composed of polyester resin, polyether resin, urethane resin, vinyl copolymer, ethylene / acrylic resin, polythiol, epoxy resin, etc.
4,4'-diphenylmethane diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, xylene diisocyanate, naphthylene-1,5 diisocyanate, polyamine and the like.

On the surface of the base sheet opposite to the heat sealant layer, that is, on the outermost surface, if necessary, a surfactant, conductive carbon black, metal deposition, conductive fine powder such as metal oxide, etc. To prevent the adhesion of dust, dust, etc. on the surface of the base sheet 2 or the generation of static electricity due to contact with other surfaces.

As the resin used for the intermediate layer, any one of a homopolymer, a copolymer and a polymer alloy can be used. Can be selected from those having a cushion effect when heat sealing. For example, besides polyester, polyethylene, ethylene / vinyl acetate copolymer, ethylene / acrylic acid copolymer, ethylene / acrylic acid ester copolymer, ionomer, ethylene / propylene rubber, polypropylene, polyethylene, SB copolymer , SB copolymer hydrogenated product, polystyrene and high-impact polystyrene, and can be formed of a polymer alloy composed of two or more resins including at least polyethylene and SB copolymer.

The intermediate layer of the present invention has a glass transition temperature of 40
It can also be formed from a linear saturated polyester having a temperature of at least ° C. Examples of the linear saturated polyester having a glass transition temperature of 40 ° C. or higher include alcohol components such as ethylene glycol, propylene glycol, 1,4-butanediol, and 1,4-cyclohexanedimethanol, and aliphatic components such as adipic acid and sebacic acid. It is a polyester obtained by dicarboxylic acid or the like with an aromatic dicarboxylic acid such as dicarboxylic acid, terephthalic acid, isophthalic acid, or diphenylcarboxylic acid. Specifically, co-condensation of ethylene glycol with terephthalic acid, ethylene glycol with isophthalic acid and / or terephthalic acid, 1,4-cyclohexanedimethanol, ethylene glycol with terephthalic acid, propylene glycol with terephthalic acid and / or isophthalic acid, and the like Use a polymer. In addition, the reason why the glass transition temperature is set to 40 ° C. or higher is that the environmental condition in which the lid material is used does not reach 40 ° C.

Further, the intermediate layer can be constituted by a layer mainly composed of the following thermoplastic resin. Polyolefin resins such as ethylene / propylene copolymer, polybutene, ethylene / butene-1 copolymer, ethylene / vinyl acetate copolymer, and ionomer. Polystyrene resins such as styrene / isoprene copolymer. Ethylene / acrylic acid copolymer, methacrylic acid copolymer, ethylene / acrylic acid ethyl ester copolymer,
Ethylene / acrylic copolymers such as ethylene / methyl acrylate copolymer and ethylene / methyl methacrylate copolymer. Adhesive resins such as co-condensation polymerized polyester and maleic anhydride-grafted polyethylene. Thermoplastic elastomer.

When butadiene is used in an amount of 250 parts by weight or more with respect to 100 parts by weight of styrene, the film is difficult to handle because of strong adhesiveness. The properties as an elastomer are degraded, and the adhesion between the carrier tape and the heat sealant layer of the lid material fluctuates when heat sealing is performed, resulting in lack of uniformity of peel strength.

The thickness of the intermediate layer of the present invention is 15 to 60 μm.
Are preferred, the inflation method using a circular die,
It can be formed in a single layer or a multilayer by a normal film forming method by a casting method using a T die. When the thickness is 15 μm or less, the cushion effect is not exerted, and the suitability for film formation is poor. 60μ
Above m, although having a cushioning effect, a large amount of heat is required for heat sealing due to the heat of dissolution, which may lower the heat seal suitability. Further, it may adversely affect the peel strength, particularly the zip-up.

The lamination of the intermediate layer and the base sheet is not limited to dry lamination via an adhesive layer, but also sandwich lamination using a general-purpose resin such as low density polyethylene via an anchor coat layer used for melt extrusion coating. it can.

The HS resin composition can be composed of ordinary thermoplastic resins, plasticizers, lubricants, antiblocking agents and antistatic agents, depending on the material of the carrier tape. Thermoplastic resins include polyurethane, vinyl chloride / vinyl acetate copolymer (including maleic anhydride, ethylene glycol, etc. as a third component), acrylic resin, polyamide containing diamine and / or dicarboxylic acid having 8 or more carbon atoms. , Ethylene-vinyl acetate copolymer, ethylene-acrylic acid copolymer, ethylene-acrylic acid ester copolymer, and a tackifier such as rosin and / or a derivative thereof,
It is formed from a mixture selected from a hydrocarbon wax and the like. The heat sealant layer may contain a dispersion stabilizer and an anti-blocking agent as necessary.

Depending on the combination of the intermediate layer and the heat sealant layer, the lid material of the present invention may be used to separate the intermediate layer and the heat sealant layer when peeling after heat sealing between the carrier tape and the lid material. Peel strength can be adjusted. In this case, a thin film of the heat sealant layer may remain between the carrier tape as the molding container and the lid material.
In such a case, the thickness of the heat sealant layer is 5 μm.
This can be prevented by making the heat sealant layer as thin as below or weakening the film strength (interlayer or rupture strength) of the heat sealant layer.

The peel strength of the lid material is 23 ° C. and a relative humidity of 4
180 ° peeling under 0% atmosphere (peeling speed 300
10/120 g / mm, more preferably 1
0 to 70 g / mm. If the peel strength is less than 10 g / mm, the heat-sealed lid material may peel off during the transport of the carrier tape, and the contents may fall off. In addition, when it is 120 g / mm or more, the carrier tape may vibrate when the lid material is peeled off, and the contents may fly out.

The zip-up is preferably 30 g / mm or less. When the zip-up exceeds 30 g / mm,
When the cover material is peeled off, the carrier tape may vibrate and the contents may fly out, which is not preferable. Note that the peel strength and the zip-up value here are 0.5 mm, as shown in FIG.
Sealed with a heat seal bar of 2 mm width x 2 rows, the average value obtained from the maximum value and the minimum value of the strength when peeled in the longitudinal direction is the peel strength, and the difference between the maximum value and the minimum value is called zip-up .

The heat sealant layer of the lid material of the present invention comprises the above-mentioned HS resin composition comprising at least one of polyester, polyurethane, vinyl chloride / vinyl acetate copolymer, acrylic resin and polyamide; ,
It is composed of conductive fine particles and the like. Examples of the combination of two or more thermoplastic resins include, for example, a composition in which 10 to 150 parts by weight of a vinyl chloride / vinyl acetate copolymer is mixed with 100 parts by weight of polyurethane, or 100 parts by weight of polyester. A mixed composition comprising 100 to 6 parts by weight of a vinyl chloride / vinyl acetate copolymer or a mixed composition comprising 100 to 6 parts by weight of a vinyl chloride / vinyl acetate copolymer per 100 parts by weight of an acrylic resin Things and the like. When the intermediate layer is made of a linear saturated polyester having a glass transition temperature of 40 ° C. or higher, it is preferable to use a mixture of polyurethane and a vinyl chloride / vinyl acetate copolymer.

The heat sealant layer of the present invention comprises an inorganic filler in an amount of 2 to 3 parts by weight per 100 parts by weight of the HS resin composition.
It is preferable to add 0 parts by weight. When the amount of the inorganic filler is 30 parts by weight or more, the transparency is reduced depending on the type of the filler, the peel strength is weak, and not only the sealing property as the cover material of the carrier tape cannot be maintained, but also the zip-up value increases. There is. If the amount of the inorganic filler is 2 parts by weight or less, blocking may occur.

The particle diameter of the inorganic filler is preferably 0.4 to 3 times the average coating thickness of the heat sealant layer. When the particle diameter is 0.4 times or less, blocking may occur because the HS resin composition is present on the surface of the heat sealant layer. On the other hand, if the ratio is three times or more, the resin fixing the particles is １ ／ or less, so that not only does the filler drop off from the coated surface, but also the transparency decreases. Further, the zip-up value becomes large, which is not preferable.

The heat sealant layer includes metal oxides such as tin oxide, zinc oxide, indium oxide and titanium oxide;
It contains conductive fine particles and organic silicon compounds obtained by imparting conductivity to sulfides such as zinc sulfide, copper sulfide, cadmium sulfide, nickel sulfide, and palladium sulfide, and sulfates such as sodium sulfate, potassium sulfate, and barium sulfate. Such conductive fine particles have a primary average particle diameter of 0.01 to 10
μm is preferred. In this case, the mixing ratio of the conductive fine particles to 100 parts by weight of the HS resin composition in the heat sealant layer is preferably in the range of 10 to 350 parts by weight. When the ratio of the conductive fine particles is less than 10, there is no antistatic effect, and when it exceeds 350, transparency is impaired, which is not preferable.

The surface resistivity of the heat sealant layer of the present invention is 10 ⁵ to 10 under the conditions of 23 ° C. and 50% relative humidity (hereinafter, the surface resistance is a value measured under these conditions unless otherwise specified). ¹² Ω / □ range and 2
500 measured at 3 ± 5 ° C. and 12 ± 3% relative humidity
It has an excellent static electricity diffusion property in which the time required to decay from 0 V to 99%, that is, the charge decay time (hereinafter referred to as charge decay time) is 2 seconds or less. If the above surface resistivity exceeds 10 ¹² Ω / □, the static electricity diffusivity decreases,
It becomes difficult to protect electronic components from electrostatic breakdown.
If it is less than 10 ⁵ Ω / □, electric current is supplied to the electronic component from the outside via the cover material, and there is a risk of electrical breakdown. On the other hand, if the charge decay time, which is an indicator of the rate of diffusion of charges generated by static electricity, exceeds 2 seconds, the effect of dispersing static electricity becomes extremely poor, making it difficult to protect electronic components from electrostatic damage. The surface resistivity and the charge decay time are measured according to MIL-B81705C in the United States.

The heat sealant layer can be formed by using a usual coating means such as a roll coat and a gravure coat. And the coating thickness is 0.1-10μ
m, preferably 1 to 5 μm.

The material of the carrier tape to be used for the cover material of the present invention is polyvinyl chloride, polystyrene, polyester, polypropylene, polycarbonate, polyacrylonitrile, ABS and the like. Alternatively, as an antistatic measure, conductive carbon black fine particles, metal fine particles, conductive fine powder obtained by imparting conductivity to a metal oxide, an organosilicon compound or a surfactant are kneaded or coated with those containing these. There are things to work on. A polystyrene or ABS resin containing carbon black on one or both sides of a polystyrene or ABS resin sheet
Examples include a multilayer sheet in which a BS resin is integrally laminated by co-extrusion, and a sheet in which a conductive polymer is formed on the surface of a plastic sheet.

Next, the lid material of the present invention will be described in more detail with reference to specific examples. (Experimental Example 1) As shown in FIG. 1, a linear polyethylene 100 having a density of 0.930 g / cm ³ was used as an EO copolymer.
A composition composed of 100 parts by weight of styrene and 55 parts by weight of butadiene and 150 parts by weight of a SB copolymer was formed as an intermediate layer 3 having a thickness of 30 μm by an inflation method using a circular die. Further, a biaxially stretched polyester film having a thickness of 12 μm as the base sheet 1 and the intermediate layer 3 were laminated by dry lamination via a polyester-isocyanate-based reactive adhesive layer 2. Next, a coating liquid in which the heat sealant layer composition shown in Table 1 was dissolved in an appropriate amount of a solvent and dispersed in a vehicle was applied to the intermediate layer 3 side by gravure reverse coating at an average coating thickness of 2 to 3 μm. The sealant layer 4 was formed, and lid materials 5 of Examples and Comparative Examples were prepared. Structure of Intermediate Layer: (Composition of Intermediate Layer) EO Copolymer: Ultrazex 3550 (trade name, manufactured by Mitsui Petrochemical Co., Ltd.) Density = 0.935 g / cm ³ 30 parts by weight SB copolymer : Asaflex 810 (trade name, manufactured by Asahi Chemical Industry Co., Ltd.) 40 parts by weight of a copolymer of 100 parts by weight of styrene and 55 parts by weight of butadiene (heat sealant layer composition) 20 parts by weight of polyurethane Nipporan 5120 [manufactured by Nippon Polyurethane Industry Co., Ltd. [Product name]-10 parts by weight of vinyl chloride / vinyl acetate copolymer vinylite VAGH [Product name by Union Carbide]-Conductive fine powder Conductive fine particles Pastrun IV Addition amount shown in Table 1) [Mitsui Metal Mining Co., Ltd.] Product name] ・ Silica (addition amount shown in Table 1) ・ Solvent (methyl ethyl ketone, ethyl acetate) Suitable amount (hereinafter abbreviated)

[0032]

[Table 1] Composition of heat sealant layer filler of Examples and Comparative Examples However, the thickness ratio of silica is a numerical value with respect to the average thickness of the heat sealant layer.

The samples of Examples and Comparative Examples were evaluated by the following methods. Table 2 shows the results. Haze value and total light transmittance: measured by Suga Test Instruments Co., Ltd. color computer SM-5SC. Surface resistivity: measured by Mitsubishi Chemical Corporation Hiresta IP at 23 ° C. and 45% relative humidity. Charge decay time: 50% at 23 ° C. and 12% relative humidity
The time required to attenuate 99% from 00V is MIL-
Measured according to B-81705C. Peel strength: Each sample slit to a width of 21.5 mm on a polyvinyl chloride carrier tape having a width of 24 mm
0 ° C, 0.4 seconds, feed pitch 12mm, seal width 0.5
Heat sealing machine (Vanguard VN-
After heat sealing at 1100), the strength was measured at 180 ° peeling using a peel strength tester (Vanguard VG-20), and the average of the maximum value and the minimum value was calculated. Zip-up value: Calculates the difference between the maximum and minimum intensity. Blocking resistance test: heat sealant layer of lid material, untreated polyethylene terephthalate and surfactant-coated polyethylene terephthalate to be the surface of the lid material, polyvinyl chloride to be the carrier tape, A.PE
T, polycarbonate, polystyrene, and the like were used as symmetric carrier tapes, each of which was stored for 14 days under conditions of a pressure of 2 kg / cm ² , storage conditions of 40 ° C., and a relative humidity of 90% for evaluation. (Evaluation criteria for blocking test) 1: No blocking. 2: Slightly adhered, but easily peeled off, with no trace. 3: When slightly adhered and peeled, the trace remains. 4: There is blocking, and the heat sealant layer partially adheres to the symmetric carrier tape. 5: There is blocking, and the heat sealant layer adheres to and peels off from the symmetric carrier tape on the entire surface. (Below)

[0034]

[Table 2] (Below)

[0035]

[Table 3] Blocking resistance test However, PET: polyethylene terephthalate Ozone protection PET: surfactant-coated polyethylene terephthalate PVC: polyvinyl chloride PC: polycarbonate PS: polystyrene,

[0036]

According to the present invention, a cover material of a carrier tape having an intermediate layer made of an SB copolymer and an EO copolymer provided on a base sheet and further provided with a heat sealant layer is made of conductive fine powder and particles. The lid material including the inorganic filler having a large diameter exhibits a stable peel strength because the intermediate layer exhibits a cushioning effect and an effect of minimizing zip-up. Further, the inorganic filler is present on the surface of the heat sealant layer and has an effect of preventing blocking.

[Brief description of the drawings]

FIG. 1 is a conceptual diagram showing a cross section of a lid material of the present invention.

FIG. 2 is a cross-sectional view showing a state in which a lid member is heat-sealed to a carrier tape.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Base sheet 2 Adhesive layer 3 Intermediate layer 4 Heat silane layer 5 Cover material 6 Filler 7 Conductive fine powder 8 HS resin composition 10 Pocket 11 Heat seal part 12 Non heat seal part

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI B32B 27/32 B32B 27/32 Z

Claims (4)

[Claims] 1. A cover material that can be heat-sealed to a carrier tape comprising a base material sheet, an intermediate layer and a heat sealant layer, wherein the base material sheet is a biaxially stretched film, and the composition of the intermediate layer is 0.900 or more. 0.940 g / cm
³ , 100 parts by weight of styrene and 10 to 1 butadiene per 100 parts by weight of the ethylene / α-olefin copolymer
A cover material for a carrier tape, comprising 50 to 250 parts by weight of a styrene / butadiene copolymer consisting of 00 parts by weight. 2. The heat sealant layer contains 10 to 350 parts by weight of a conductive fine powder of tin oxide, zinc oxide, indium oxide, and titanium oxide based on 100 parts by weight of the heat-sealing resin composition. 2-3 inorganic fillers
The cover material for a carrier tape according to claim 1, wherein the cover material contains 0 parts by weight. 3. The carrier tape according to claim 1, wherein the particle diameter of the inorganic filler is 0.4 to 3 times the average coating thickness of the heat sealant layer. 4. The carrier tape cover according to claim 1, wherein the surface resistivity of the heat sealant layer is 10 ^{5 to} 10 ¹² Ω / □, and the charge decay time does not exceed 2 seconds. Wood.